Merge branch 'master' into cmake

1 files changed, 3268 insertions, 2803 deletions

diff --git a/doc/gawktexi.in b/doc/gawktexi.in
index 875893f1..4cd04763 100644
--- a/doc/gawktexi.in
+++ b/doc/gawktexi.in
@@ -32,13 +32,11 @@
 @ifnotdocbook
 @set BULLET @bullet{}
 @set MINUS @minus{}
-@set NUL @sc{nul}
 @end ifnotdocbook
 
 @ifdocbook
 @set BULLET
 @set MINUS
-@set NUL NUL
 @end ifdocbook
 
 @set xref-automatic-section-title
@@ -48,12 +46,13 @@
 @c applies to and all the info about who's publishing this edition
 
 @c These apply across the board.
-@set UPDATE-MONTH September, 2014
+@set UPDATE-MONTH February, 2015
 @set VERSION 4.1
 @set PATCHLEVEL 2
 
+@set GAWKINETTITLE TCP/IP Internetworking with @command{gawk}
 @ifset FOR_PRINT
-@set TITLE Effective AWK Programming
+@set TITLE Effective awk Programming
 @end ifset
 @ifclear FOR_PRINT
 @set TITLE GAWK: Effective AWK Programming
@@ -172,19 +171,31 @@
 @macro DBREF{text}
 @ref{\text\}
 @end macro
+@macro DBXREF{text}
+@xref{\text\}
+@end macro
+@macro DBPXREF{text}
+@pxref{\text\}
+@end macro
 @end ifdocbook
 
 @ifnotdocbook
 @macro DBREF{text}
 @ref{\text\},
 @end macro
+@macro DBXREF{text}
+@xref{\text\},
+@end macro
+@macro DBPXREF{text}
+@pxref{\text\},
+@end macro
 @end ifnotdocbook
 
 @ifclear FOR_PRINT
 @set FN file name
-@set FFN File Name
+@set FFN File name
 @set DF data file
-@set DDF Data File
+@set DDF Data file
 @set PVERSION version
 @end ifclear
 @ifset FOR_PRINT
@@ -192,7 +203,7 @@
 @set FFN Filename
 @set DF datafile
 @set DDF Datafile
-@set PVERSION Version
+@set PVERSION version
 @end ifset
 
 @c For HTML, spell out email addresses, to avoid problems with
@@ -283,13 +294,13 @@ Fax: +1-617-542-2652
 Email: <email>gnu@@gnu.org</email>
 URL: <ulink url="http://www.gnu.org">http://www.gnu.org/</ulink></literallayout>
 
-<literallayout class="normal">Copyright &copy; 1989, 1991, 1992, 1993, 1996&ndash;2005, 2007, 2009&ndash;2014
+<literallayout class="normal">Copyright &copy; 1989, 1991, 1992, 1993, 1996&ndash;2005, 2007, 2009&ndash;2015
 Free Software Foundation, Inc.
 All Rights Reserved.</literallayout>
 @end docbook
 
 @ifnotdocbook
-Copyright @copyright{} 1989, 1991, 1992, 1993, 1996--2005, 2007, 2009--2014 @*
+Copyright @copyright{} 1989, 1991, 1992, 1993, 1996--2005, 2007, 2009--2015 @*
 Free Software Foundation, Inc.
 @end ifnotdocbook
 @sp 2
@@ -312,7 +323,7 @@ A copy of the license is included in the section entitled
 A copy of the license
 may be found on the Internet at
 @uref{http://www.gnu.org/software/gawk/manual/html_node/GNU-Free-Documentation-License.html,
-the GNU Project's web site}.
+the GNU Project's website}.
 @end ifset
 
 @enumerate a
@@ -380,10 +391,10 @@ ISBN 1-882114-28-0 @*
 @sp 9
 @center @i{To my parents, for their love, and for the wonderful example they set for me.}
 @sp 1
-@center @i{To my wife Miriam, for making me complete.
+@center @i{To my wife, Miriam, for making me complete.
 Thank you for building your life together with me.}
 @sp 1
-@center @i{To our children Chana, Rivka, Nachum and Malka, for enrichening our lives in innumerable ways.}
+@center @i{To our children, Chana, Rivka, Nachum, and Malka, for enrichening our lives in innumerable ways.}
 @sp 1
 @w{ }
 @page
@@ -428,8 +439,9 @@ particular records in a file and perform operations upon them.
 @end ifnottex
 
 @menu
-* Foreword::                       Some nice words about this
+* Foreword3::                      Some nice words about this
                                    @value{DOCUMENT}.
+* Foreword4::                      More nice words.
 * Preface::                        What this @value{DOCUMENT} is about; brief
                                    history and acknowledgments.
 * Getting Started::                A basic introduction to using
@@ -456,7 +468,7 @@ particular records in a file and perform operations upon them.
                                    @command{gawk}.
 * Internationalization::           Getting @command{gawk} to speak your
                                    language.
-* Debugger::                       The @code{gawk} debugger.
+* Debugger::                       The @command{gawk} debugger.
 * Arbitrary Precision Arithmetic:: Arbitrary precision arithmetic with
                                    @command{gawk}.
 * Dynamic Extensions::             Adding new built-in functions to
@@ -587,6 +599,7 @@ particular records in a file and perform operations upon them.
                                         @code{getline}.
 * Getline Summary::                     Summary of @code{getline} Variants.
 * Read Timeout::                        Reading input with a timeout.
+* Retrying Input::                      Retrying input after certain errors.
 * Command-line directories::            What happens if you put a directory on
                                         the command line.
 * Input Summary::                       Input summary.
@@ -616,6 +629,7 @@ particular records in a file and perform operations upon them.
 * Special Caveats::                     Things to watch out for.
 * Close Files And Pipes::               Closing Input and Output Files and
                                         Pipes.
+* Nonfatal::                            Enabling Nonfatal Output.
 * Output Summary::                      Output summary.
 * Output Exercises::                    Exercises.
 * Values::                              Constants, Variables, and Regular
@@ -927,6 +941,7 @@ particular records in a file and perform operations upon them.
 * Array Functions::                     Functions for working with arrays.
 * Flattening Arrays::                   How to flatten arrays.
 * Creating Arrays::                     How to create and populate arrays.
+* Redirection API::                     How to access and manipulate redirections.
 * Extension API Variables::             Variables provided by the API.
 * Extension Versioning::                API Version information.
 * Extension API Informational Variables:: Variables providing information about
@@ -939,7 +954,7 @@ particular records in a file and perform operations upon them.
 * Internal File Ops::                   The code for internal file operations.
 * Using Internal File Ops::             How to use an external extension.
 * Extension Samples::                   The sample extensions that ship with
-                                        @code{gawk}.
+                                        @command{gawk}.
 * Extension Sample File Functions::     The file functions sample.
 * Extension Sample Fnmatch::            An interface to @code{fnmatch()}.
 * Extension Sample Fork::               An interface to @code{fork()} and
@@ -985,6 +1000,7 @@ particular records in a file and perform operations upon them.
 * Unix Installation::                   Installing @command{gawk} under
                                         various versions of Unix.
 * Quick Installation::                  Compiling @command{gawk} under Unix.
+* Shell Startup Files::                 Shell convenience functions.
 * Additional Configuration Options::    Other compile-time options.
 * Configuration Philosophy::            How it's all supposed to work.
 * Non-Unix Installation::               Installation on Other Operating
@@ -1057,8 +1073,8 @@ for enrichening our lives in innumerable ways.
 @summarycontents
 @contents
 
-@node Foreword
-@unnumbered Foreword
+@node Foreword3
+@unnumbered Foreword to the Third Edition
 
 @c This bit is post-processed by a script which turns the chapter
 @c tag into a preface tag, and moves this stuff to before the title.
@@ -1071,7 +1087,7 @@ for enrichening our lives in innumerable ways.
       <!-- can't put mawk into command tags. sigh. -->
       <affiliation><jobtitle>Author of mawk</jobtitle></affiliation>
     </author>
-    <date>March, 2001</date>
+    <date>March 2001</date>
    </prefaceinfo>
 @end docbook
 
@@ -1083,21 +1099,23 @@ The circumstances started a couple of years
 earlier. I was working at a new job and noticed an unplugged
 Unix computer sitting in the corner.  No one knew how to use it,
 and neither did I.  However,
-a couple of days later it was running, and
+a couple of days later, it was running, and
 I was @code{root} and the one-and-only user.
 That day, I began the transition from statistician to Unix programmer.
 
 On one of many trips to the library or bookstore in search of
-books on Unix, I found the gray AWK book, a.k.a.@: Aho, Kernighan and
-Weinberger, @cite{The AWK Programming Language}, Addison-Wesley,
-1988.  AWK's simple programming paradigm---find a pattern in the
+books on Unix, I found the gray AWK book, a.k.a.@:
+Alfred V.@: Aho, Brian W.@: Kernighan, and
+Peter J.@: Weinberger's @cite{The AWK Programming Language} (Addison-Wesley,
+1988).  @command{awk}'s simple programming paradigm---find a pattern in the
 input and then perform an action---often reduced complex or tedious
 data manipulations to a few lines of code.  I was excited to try my
 hand at programming in AWK.
 
 Alas,  the @command{awk} on my computer was a limited version of the
-language described in the AWK book.  I discovered that my computer
-had ``old @command{awk}'' and the AWK book described ``new @command{awk}.''
+language described in the gray book.  I discovered that my computer
+had ``old @command{awk}'' and the book described
+``new @command{awk}.''
 I learned that this was typical; the old version refused to step
 aside or relinquish its name.  If a system had a new @command{awk}, it was
 invariably called @command{nawk}, and few systems had it.
@@ -1115,7 +1133,7 @@ My Unix system started out unplugged from the wall; it certainly was not
 plugged into a network.  So, oblivious to the existence of @command{gawk}
 and the Unix community in general, and desiring a new @command{awk}, I wrote
 my own, called @command{mawk}.
-Before I was finished I knew about @command{gawk},
+Before I was finished, I knew about @command{gawk},
 but it was too late to stop, so I eventually posted
 to a @code{comp.sources} newsgroup.
 
@@ -1124,7 +1142,7 @@ from Arnold introducing
 himself.   He suggested we share design and algorithms and
 attached a draft of the POSIX standard so
 that I could update @command{mawk} to support language extensions added
-after publication of the AWK book.
+after publication of @cite{The AWK Programming Language}.
 
 Frankly, if our roles had
 been reversed, I would not have been so open and we probably would
@@ -1143,7 +1161,7 @@ standard.
 On the other hand, the novice AWK programmer can study
 a wealth of practical programs that emphasize
 the power of AWK's basic idioms:
-data driven control-flow, pattern matching with regular expressions,
+data-driven control flow, pattern matching with regular expressions,
 and associative arrays.
 Those looking for something new can try out @command{gawk}'s
 interface to network protocols via special @file{/inet} files.
@@ -1151,7 +1169,7 @@ interface to network protocols via special @file{/inet} files.
 The programs in this book make clear that an AWK program is
 typically much smaller and faster to develop than
 a counterpart written in C.
-Consequently, there is often a payoff to prototype an
+Consequently, there is often a payoff to prototyping an
 algorithm or design in AWK to get it running quickly and expose
 problems early. Often, the interpreted performance is adequate
 and the AWK prototype becomes the product.
@@ -1204,7 +1222,62 @@ AWK or want to learn how, then read this book.
 @display
 Michael Brennan
 Author of @command{mawk}
-March, 2001
+March 2001
+@end display
+@end ifnotdocbook
+
+@node Foreword4
+@unnumbered Foreword to the Fourth Edition
+
+@c This bit is post-processed by a script which turns the chapter
+@c tag into a preface tag, and moves this stuff to before the title.
+@c Bleah.
+@docbook
+  <prefaceinfo>
+    <author>
+      <firstname>Michael</firstname>
+      <surname>Brennan</surname>
+      <!-- can't put mawk into command tags. sigh. -->
+      <affiliation><jobtitle>Author of mawk</jobtitle></affiliation>
+    </author>
+    <date>October 2014</date>
+   </prefaceinfo>
+@end docbook
+
+Some things don't change.  Thirteen years ago I wrote:
+``If you use AWK or want to learn how, then read this book.''
+True then, and still true today.
+
+Learning to use a programming language is about more than mastering the
+syntax.  One needs to acquire an understanding of how to use the
+features of the language to solve practical programming problems.
+A focus of this book is many examples that show how to use AWK.
+
+Some things do change. Our computers are much faster and have more memory.
+Consequently, speed and storage inefficiencies of a high-level language
+matter less.  Prototyping in AWK and then rewriting in C for performance
+reasons happens less, because more often the prototype is fast enough.
+
+Of course, there are computing operations that are best done in C or C++.
+With @command{gawk} 4.1 and later, you do not have to choose between writing
+your program in AWK or in C/C++.  You can write most of your
+program in AWK and the aspects that require C/C++ capabilities can be written
+in C/C++, and then the pieces glued together when the @command{gawk} module loads
+the C/C++ module as a dynamic plug-in.
+@c Chapter 16
+@ref{Dynamic Extensions},
+has all the
+details, and, as expected, many examples to help you learn the ins and outs.
+
+I enjoy programming in AWK and had fun (re)reading this book.
+I think you will too.
+
+@ifnotdocbook
+@cindex Brennan, Michael
+@display
+Michael Brennan
+Author of @command{mawk}
+October 2014
 @end display
 @end ifnotdocbook
 
@@ -1224,9 +1297,9 @@ March, 2001
       <firstname>Arnold</firstname>
       <surname>Robbins</surname>
       <affiliation><jobtitle>Nof Ayalon</jobtitle></affiliation>
-      <affiliation><jobtitle>ISRAEL</jobtitle></affiliation>
+      <affiliation><jobtitle>Israel</jobtitle></affiliation>
     </author>
-    <date>December, 2014</date>
+    <date>February 2015</date>
    </prefaceinfo>
 @end docbook
 
@@ -1238,7 +1311,7 @@ The @command{awk} utility interprets a special-purpose programming
 language that makes it easy to handle simple data-reformatting jobs.
 
 The GNU implementation of @command{awk} is called @command{gawk}; if you
-invoke it with the proper options or environment variables
+invoke it with the proper options or environment variables,
 it is fully compatible with
 the POSIX@footnote{The 2008 POSIX standard is accessible online at
 @w{@url{http://www.opengroup.org/onlinepubs/9699919799/}.}}
@@ -1269,7 +1342,7 @@ Generate reports
 Validate data
 
 @item
-Produce indexes and perform other document preparation tasks
+Produce indexes and perform other document-preparation tasks
 
 @item
 Experiment with algorithms that you can adapt later to other computer
@@ -1345,7 +1418,7 @@ has been removed.}
 @unnumberedsec History of @command{awk} and @command{gawk}
 @cindex recipe for a programming language
 @cindex programming language, recipe for
-@sidebar Recipe For A Programming Language
+@sidebar Recipe for a Programming Language
 
 @multitable {2 parts} {1 part  @code{egrep}} {1 part  @code{snobol}}
 @item @tab 1 part  @code{egrep} @tab 1 part  @code{snobol}
@@ -1364,7 +1437,7 @@ more parts C.  Document very well and release.
 @cindex Kernighan, Brian
 @cindex @command{awk}, history of
 The name @command{awk} comes from the initials of its designers: Alfred V.@:
-Aho, Peter J.@: Weinberger and Brian W.@: Kernighan.  The original version of
+Aho, Peter J.@: Weinberger, and Brian W.@: Kernighan.  The original version of
 @command{awk} was written in 1977 at AT&T Bell Laboratories.
 In 1985, a new version made the programming
 language more powerful, introducing user-defined functions, multiple input
@@ -1388,23 +1461,23 @@ help from me, thoroughly reworked @command{gawk} for compatibility
 with the newer @command{awk}.
 Circa 1994, I became the primary maintainer.
 Current development focuses on bug fixes,
-performance improvements, standards compliance and, occasionally, new features.
+performance improvements, standards compliance, and, occasionally, new features.
 
-In May of 1997, J@"urgen Kahrs felt the need for network access
+In May 1997, J@"urgen Kahrs felt the need for network access
 from @command{awk}, and with a little help from me, set about adding
 features to do this for @command{gawk}.  At that time, he also
 wrote the bulk of
-@cite{TCP/IP Internetworking with @command{gawk}}
+@cite{@value{GAWKINETTITLE}}
 (a separate document, available as part of the @command{gawk} distribution).
 His code finally became part of the main @command{gawk} distribution
 with @command{gawk} @value{PVERSION} 3.1.
 
 John Haque rewrote the @command{gawk} internals, in the process providing
 an @command{awk}-level debugger. This version became available as
-@command{gawk} @value{PVERSION} 4.0, in 2011.
+@command{gawk} @value{PVERSION} 4.0 in 2011.
 
-@xref{Contributors},
-for a full list of those who made important contributions to @command{gawk}.
+@DBXREF{Contributors}
+for a full list of those who have made important contributions to @command{gawk}.
 
 @node Names
 @unnumberedsec A Rose by Any Other Name
@@ -1413,11 +1486,11 @@ for a full list of those who made important contributions to @command{gawk}.
 The @command{awk} language has evolved over the years. Full details are
 provided in @ref{Language History}.
 The language described in this @value{DOCUMENT}
-is often referred to as ``new @command{awk}''.
+is often referred to as ``new @command{awk}.''
 By analogy, the original version of @command{awk} is
 referred to as ``old @command{awk}.''
 
-Today, on most systems, when you run the @command{awk} utility,
+On most current systems, when you run the @command{awk} utility
 you get some version of new @command{awk}.@footnote{Only
 Solaris systems still use an old @command{awk} for the
 default @command{awk} utility. A more modern @command{awk} lives in
@@ -1477,7 +1550,9 @@ the POSIX standard for @command{awk}.
 This @value{DOCUMENT} has the difficult task of being both a tutorial and a reference.
 If you are a novice, feel free to skip over details that seem too complex.
 You should also ignore the many cross-references; they are for the
-expert user and for the online Info and HTML versions of the @value{DOCUMENT}.
+expert user and for the Info and
+@uref{http://www.gnu.org/software/gawk/manual/, HTML}
+versions of the @value{DOCUMENT}.
 @end ifnotinfo
 
 There are sidebars
@@ -1492,12 +1567,15 @@ Most of the time, the examples use complete @command{awk} programs.
 Some of the more advanced sections show only the part of the @command{awk}
 program that illustrates the concept being described.
 
-While this @value{DOCUMENT} is aimed principally at people who have not been
+Although this @value{DOCUMENT} is aimed principally at people who have not been
 exposed
 to @command{awk}, there is a lot of information here that even the @command{awk}
 expert should find useful.  In particular, the description of POSIX
 @command{awk} and the example programs in
-@ref{Library Functions}, and in
+@ref{Library Functions}, and
+@ifnotdocbook
+in
+@end ifnotdocbook
 @ref{Sample Programs},
 should be of interest.
 
@@ -1505,22 +1583,30 @@ This @value{DOCUMENT} is split into several parts, as follows:
 
 @c FULLXREF ON
 
-Part I describes the @command{awk} language and @command{gawk} program in detail.
+@itemize @value{BULLET}
+@item
+Part I describes the @command{awk} language and the @command{gawk} program in detail.
 It starts with the basics, and continues through all of the features of @command{awk}.
 It contains the following chapters:
 
+@c nested
+@itemize @value{MINUS}
+@item
 @ref{Getting Started},
 provides the essentials you need to know to begin using @command{awk}.
 
+@item
 @ref{Invoking Gawk},
 describes how to run @command{gawk}, the meaning of its
 command-line options, and how it finds @command{awk}
 program source files.
 
+@item
 @ref{Regexp},
 introduces regular expressions in general, and in particular the flavors
 supported by POSIX @command{awk} and @command{gawk}.
 
+@item
 @ref{Reading Files},
 describes how @command{awk} reads your data.
 It introduces the concepts of records and fields, as well
@@ -1528,46 +1614,62 @@ as the @code{getline} command.
 I/O redirection is first described here.
 Network I/O is also briefly introduced here.
 
+@item
 @ref{Printing},
 describes how @command{awk} programs can produce output with
 @code{print} and @code{printf}.
 
+@item
 @ref{Expressions},
 describes expressions, which are the basic building blocks
 for getting most things done in a program.
 
+@item
 @ref{Patterns and Actions},
 describes how to write patterns for matching records, actions for
 doing something when a record is matched, and the predefined variables
 @command{awk} and @command{gawk} use.
 
+@item
 @ref{Arrays},
-covers @command{awk}'s one-and-only data structure: associative arrays.
-Deleting array elements and whole arrays is also described, as well as
-sorting arrays in @command{gawk}.  It also describes how @command{gawk}
-provides arrays of arrays.
+covers @command{awk}'s one-and-only data structure: the associative array.
+Deleting array elements and whole arrays is described, as well as
+sorting arrays in @command{gawk}.  The @value{CHAPTER} also describes how
+@command{gawk} provides arrays of arrays.
 
+@item
 @ref{Functions},
 describes the built-in functions @command{awk} and @command{gawk} provide,
 as well as how to define your own functions.  It also discusses how
 @command{gawk} lets you call functions indirectly.
+@end itemize
 
+@item
 Part II shows how to use @command{awk} and @command{gawk} for problem solving.
 There is lots of code here for you to read and learn from.
-It contains the following chapters:
+This part contains the following chapters:
 
-@ref{Library Functions}, which provides a number of functions meant to
+@c nested
+@itemize @value{MINUS}
+@item
+@ref{Library Functions}, provides a number of functions meant to
 be used from main @command{awk} programs.
 
+@item
 @ref{Sample Programs},
-which provides many sample @command{awk} programs.
+provides many sample @command{awk} programs.
+@end itemize
 
 Reading these two chapters allows you to see @command{awk}
 solving real problems.
 
+@item
 Part III focuses on features specific to @command{gawk}.
 It contains the following chapters:
 
+@c nested
+@itemize @value{MINUS}
+@item
 @ref{Advanced Features},
 describes a number of advanced features.
 Of particular note
@@ -1576,18 +1678,24 @@ have two-way communications with another process,
 perform TCP/IP networking, and
 profile your @command{awk} programs.
 
+@item
 @ref{Internationalization},
 describes special features for translating program
 messages into different languages at runtime.
 
+@item
 @ref{Debugger}, describes the @command{gawk} debugger.
 
+@item
 @ref{Arbitrary Precision Arithmetic},
 describes advanced arithmetic facilities.
 
+@item
 @ref{Dynamic Extensions}, describes how to add new variables and
 functions to @command{gawk} by writing extensions in C or C++.
+@end itemize
 
+@item
 @ifclear FOR_PRINT
 Part IV provides the appendices, the Glossary, and two licenses that cover
 the @command{gawk} source code and this @value{DOCUMENT}, respectively.
@@ -1598,11 +1706,14 @@ Part IV provides the following appendices,
 including the GNU General Public License:
 @end ifset
 
+@itemize @value{MINUS}
+@item
 @ref{Language History},
 describes how the @command{awk} language has evolved since
-its first release to present.  It also describes how @command{gawk}
+its first release to the present.  It also describes how @command{gawk}
 has acquired features over time.
 
+@item
 @ref{Installation},
 describes how to get @command{gawk}, how to compile it
 on POSIX-compatible systems,
@@ -1612,15 +1723,44 @@ in @command{gawk} and where to get other freely
 available @command{awk} implementations.
 
 @ifset FOR_PRINT
-
+@item
 @ref{Copying},
 presents the license that covers the @command{gawk} source code.
+@end ifset
+
+@ifclear FOR_PRINT
+@item
+@ref{Notes},
+describes how to disable @command{gawk}'s extensions, as
+well as how to contribute new code to @command{gawk},
+and some possible future directions for @command{gawk} development.
+
+@item
+@ref{Basic Concepts},
+provides some very cursory background material for those who
+are completely unfamiliar with computer programming.
+
+The @ref{Glossary}, defines most, if not all, of the significant terms used
+throughout the @value{DOCUMENT}.  If you find terms that you aren't familiar with,
+try looking them up here.
 
+@item
+@ref{Copying}, and
+@ref{GNU Free Documentation License},
+present the licenses that cover the @command{gawk} source code
+and this @value{DOCUMENT}, respectively.
+@end ifclear
+@end itemize
+@end itemize
+
+@ifset FOR_PRINT
 The version of this @value{DOCUMENT} distributed with @command{gawk}
 contains additional appendices and other end material.
 To save space, we have omitted them from the
 printed edition. You may find them online, as follows:
 
+@itemize @value{BULLET}
+@item
 @uref{http://www.gnu.org/software/gawk/manual/html_node/Notes.html,
 The appendix on implementation notes}
 describes how to disable @command{gawk}'s extensions, how to contribute
@@ -1628,45 +1768,29 @@ new code to @command{gawk}, where to find information on some possible
 future directions for @command{gawk} development, and the design decisions
 behind the extension API.
 
+@item
 @uref{http://www.gnu.org/software/gawk/manual/html_node/Basic-Concepts.html,
 The appendix on basic concepts}
 provides some very cursory background material for those who
 are completely unfamiliar with computer programming.
 
+@item
 @uref{http://www.gnu.org/software/gawk/manual/html_node/Glossary.html,
 The Glossary}
-defines most, if not all, the significant terms used
+defines most, if not all, of the significant terms used
 throughout the @value{DOCUMENT}.  If you find terms that you aren't familiar with,
 try looking them up here.
 
+@item
 @uref{http://www.gnu.org/software/gawk/manual/html_node/GNU-Free-Documentation-License.html,
 The GNU FDL}
 is the license that covers this @value{DOCUMENT}.
+@end itemize
 
 Some of the chapters have exercise sections; these have also been
 omitted from the print edition but are available online.
 @end ifset
 
-@ifclear FOR_PRINT
-@ref{Notes},
-describes how to disable @command{gawk}'s extensions, as
-well as how to contribute new code to @command{gawk},
-and some possible future directions for @command{gawk} development.
-
-@ref{Basic Concepts},
-provides some very cursory background material for those who
-are completely unfamiliar with computer programming.
-
-The @ref{Glossary}, defines most, if not all, the significant terms used
-throughout the @value{DOCUMENT}.  If you find terms that you aren't familiar with,
-try looking them up here.
-
-@ref{Copying}, and
-@ref{GNU Free Documentation License},
-present the licenses that cover the @command{gawk} source code
-and this @value{DOCUMENT}, respectively.
-@end ifclear
-
 @c FULLXREF OFF
 
 @node Conventions
@@ -1697,7 +1821,7 @@ This typically represents the command's standard output.
 Output from the command, usually its standard output, appears
 @code{like this}.
 @end ifset
-Error messages, and other output on the command's standard error, are preceded
+Error messages and other output on the command's standard error are preceded
 by the glyph ``@error{}''.  For example:
 
 @example
@@ -1708,15 +1832,23 @@ $ @kbd{echo hello on stderr 1>&2}
 @end example
 
 @ifnotinfo
-In the text, command names appear in @code{this font}, while code segments
+In the text, almost anything related to programming, such as
+command names,
+variable and function names, and string, numeric and regexp constants
+appear in @code{this font}. Code fragments
 appear in the same font and quoted, @samp{like this}.
+Things that are replaced by the user or programmer
+appear in @var{this font}.
 Options look like this: @option{-f}.
+@value{FFN}s are indicated like this: @file{/path/to/ourfile}.
+@ifclear FOR_PRINT
 Some things are
 emphasized @emph{like this}, and if a point needs to be made
-strongly, it is done @strong{like this}.  The first occurrence of
+strongly, it is done @strong{like this}.
+@end ifclear
+The first occurrence of
 a new term is usually its @dfn{definition} and appears in the same
 font as the previous occurrence of ``definition'' in this sentence.
-Finally, @value{FN}s are indicated like this: @file{/path/to/ourfile}.
 @end ifnotinfo
 
 Characters that you type at the keyboard look @kbd{like this}.  In particular,
@@ -1724,11 +1856,11 @@ there are special characters called ``control characters.''  These are
 characters that you type by holding down both the @kbd{CONTROL} key and
 another key, at the same time.  For example, a @kbd{Ctrl-d} is typed
 by first pressing and holding the @kbd{CONTROL} key, next
-pressing the @kbd{d} key and finally releasing both keys.
+pressing the @kbd{d} key, and finally releasing both keys.
 
 For the sake of brevity, throughout this @value{DOCUMENT}, we refer to
 Brian Kernighan's version of @command{awk} as ``BWK @command{awk}.''
-(@xref{Other Versions}, for information on his and other versions.)
+(@DBXREF{Other Versions} for information on his and other versions.)
 
 @ifset FOR_PRINT
 @quotation NOTE
@@ -1744,7 +1876,7 @@ Cautionary or warning notes look like this.
 @unnumberedsubsec Dark Corners
 @cindex Kernighan, Brian
 @quotation
-@i{Dark corners are basically fractal --- no matter how much
+@i{Dark corners are basically fractal---no matter how much
 you illuminate, there's always a smaller but darker one.}
 @author Brian Kernighan
 @end quotation
@@ -1760,7 +1892,7 @@ the picture of a flashlight in the margin, as shown here.
 @value{DARKCORNER}
 @end iftex
 @ifnottex
-``(d.c.)''.
+``(d.c.).''
 @end ifnottex
 @ifclear FOR_PRINT
 They also appear in the index under the heading ``dark corner.''
@@ -1795,12 +1927,12 @@ Emacs editor.  GNU Emacs is the most widely used version of Emacs today.
 @cindex GPL (General Public License)
 @cindex General Public License, See GPL
 @cindex documentation, online
-The GNU@footnote{GNU stands for ``GNU's not Unix.''}
+The GNU@footnote{GNU stands for ``GNU's Not Unix.''}
 Project is an ongoing effort on the part of the Free Software
 Foundation to create a complete, freely distributable, POSIX-compliant
 computing environment.
-The FSF uses the ``GNU General Public License'' (GPL) to ensure that
-their software's
+The FSF uses the GNU General Public License (GPL) to ensure that
+its software's
 source code is always available to the end user.
 @ifclear FOR_PRINT
 A copy of the GPL is included
@@ -1814,7 +1946,7 @@ The GPL applies to the C language source code for @command{gawk}.
 To find out more about the FSF and the GNU Project online,
 see @uref{http://www.gnu.org, the GNU Project's home page}.
 This @value{DOCUMENT} may also be read from
-@uref{http://www.gnu.org/software/gawk/manual/, their web site}.
+@uref{http://www.gnu.org/software/gawk/manual/, GNU's website}.
 
 @ifclear FOR_PRINT
 A shell, an editor (Emacs), highly portable optimizing C, C++, and
@@ -1851,16 +1983,16 @@ License in @ref{GNU Free Documentation License}.)
 @cindex Close, Diane
 The @value{DOCUMENT} itself has gone through multiple previous editions.
 Paul Rubin wrote the very first draft of @cite{The GAWK Manual};
-it was around 40 pages in size.
+it was around 40 pages long.
 Diane Close and Richard Stallman improved it, yielding a
 version that was
-around 90 pages long and barely described the original, ``old''
+around 90 pages and barely described the original, ``old''
 version of @command{awk}.
 
 I started working with that version in the fall of 1988.
 As work on it progressed,
 the FSF published several preliminary versions (numbered 0.@var{x}).
-In 1996, Edition 1.0 was released with @command{gawk} 3.0.0.
+In 1996, edition 1.0 was released with @command{gawk} 3.0.0.
 The FSF published the first two editions under
 the title @cite{The GNU Awk User's Guide}.
 @ifset FOR_PRINT
@@ -1872,7 +2004,7 @@ the third edition in 2001.
 This edition maintains the basic structure of the previous editions.
 For FSF edition 4.0, the content was thoroughly reviewed and updated. All
 references to @command{gawk} versions prior to 4.0 were removed.
-Of significant note for that edition was @ref{Debugger}.
+Of significant note for that edition was the addition of @ref{Debugger}.
 
 For FSF edition
 @ifclear FOR_PRINT
@@ -1887,17 +2019,17 @@ and the major new additions are @ref{Arbitrary Precision Arithmetic},
 and @ref{Dynamic Extensions}.
 
 This @value{DOCUMENT} will undoubtedly continue to evolve.  If you
-find an error in this @value{DOCUMENT}, please report it!  @xref{Bugs},
+find an error in the @value{DOCUMENT}, please report it!  @DBXREF{Bugs}
 for information on submitting problem reports electronically.
 
 @ifset FOR_PRINT
 @c fakenode --- for prepinfo
 @unnumberedsec How to Stay Current
 
-It may be you have a version of @command{gawk} which is newer than the
+You may have a newer version of @command{gawk} than the
 one described here.  To find out what has changed,
 you should first look at the @file{NEWS} file in the @command{gawk}
-distribution, which provides a high level summary of what changed in
+distribution, which provides a high-level summary of the changes in
 each release.
 
 You can then look at the @uref{http://www.gnu.org/software/gawk/manual/,
@@ -1922,16 +2054,18 @@ contributed code: the archive did not grow and the domain went unused
 for several years.
 
 Late in 2008, a volunteer took on the task of setting up
-an @command{awk}-related web site---@uref{http://awk.info}---and did a very
+an @command{awk}-related website---@uref{http://awk.info}---and did a very
 nice job.
 
 If you have written an interesting @command{awk} program, or have written
 a @command{gawk} extension that you would like to share with the rest
 of the world, please see @uref{http://awk.info/?contribute} for how to
-contribute it to the web site.
+contribute it to the website.
 
+@ignore
 As of this writing, this website is in search of a maintainer; please
 contact me if you are interested.
+@end ignore
 
 @ignore
 Other links:
@@ -1949,7 +2083,7 @@ The initial draft of @cite{The GAWK Manual} had the following acknowledgments:
 Many people need to be thanked for their assistance in producing this
 manual.  Jay Fenlason contributed many ideas and sample programs.  Richard
 Mlynarik and Robert Chassell gave helpful comments on drafts of this
-manual.  The paper @cite{A Supplemental Document for @command{awk}} by John W.@:
+manual.  The paper @cite{A Supplemental Document for AWK} by John W.@:
 Pierce of the Chemistry Department at UC San Diego, pinpointed several
 issues relevant both to @command{awk} implementation and to this manual, that
 would otherwise have escaped us.
@@ -1960,12 +2094,18 @@ I would like to acknowledge Richard M.@: Stallman, for his vision of a
 better world and for his courage in founding the FSF and starting the
 GNU Project.
 
+@ifclear FOR_PRINT
 Earlier editions of this @value{DOCUMENT} had the following acknowledgements:
+@end ifclear
+@ifset FOR_PRINT
+The previous edition of this @value{DOCUMENT} had
+the following acknowledgements:
+@end ifset
 
 @quotation
 The following people (in alphabetical order)
 provided helpful comments on various
-versions of this book,
+versions of this book:
 Rick Adams,
 Dr.@: Nelson H.F. Beebe,
 Karl Berry,
@@ -1993,7 +2133,7 @@ Robert J.@: Chassell provided much valuable advice on
 the use of Texinfo.
 He also deserves special thanks for
 convincing me @emph{not} to title this @value{DOCUMENT}
-@cite{How To Gawk Politely}.
+@cite{How to Gawk Politely}.
 Karl Berry helped significantly with the @TeX{} part of Texinfo.
 
 @cindex Hartholz, Marshall
@@ -2073,38 +2213,39 @@ portable program it is today.  It has been and continues to be a pleasure
 working with this team of fine people.
 
 Notable code and documentation contributions were made by
-a number of people. @xref{Contributors}, for the full list.
+a number of people. @DBXREF{Contributors} for the full list.
 
 @ifset FOR_PRINT
 @cindex Oram, Andy
-Thanks to Andy Oram, of O'Reilly Media, for initiating
+Thanks to Andy Oram of O'Reilly Media for initiating
 the fourth edition and for his support during the work.
+Thanks to Jasmine Kwityn for her copyediting work.
 @end ifset
 
-Thanks to Michael Brennan for the Foreword.
+Thanks to Michael Brennan for the Forewords.
 
 @cindex Duman, Patrice
 @cindex Berry, Karl
 Thanks to Patrice Dumas for the new @command{makeinfo} program.
-Thanks to Karl Berry who continues to work to keep
+Thanks to Karl Berry, who continues to work to keep
 the Texinfo markup language sane.
 
 @cindex Kernighan, Brian
 @cindex Brennan, Michael
 @cindex Day, Robert P.J.@:
-Robert P.J.@: Day, Michael Brennan and Brian Kernighan kindly acted as
+Robert P.J.@: Day, Michael Brennan, and Brian Kernighan kindly acted as
 reviewers for the 2015 edition of this @value{DOCUMENT}. Their feedback
 helped improve the final work.
 
-I would like to thank Brian Kernighan for invaluable assistance during the
-testing and debugging of @command{gawk}, and for ongoing
+I would also like to thank Brian Kernighan for his invaluable assistance during the
+testing and debugging of @command{gawk}, and for his ongoing
 help and advice in clarifying numerous points about the language.
 We could not have done nearly as good a job on either @command{gawk}
 or its documentation without his help.
 
 Brian is in a class by himself as a programmer and technical
 author.  I have to thank him (yet again) for his ongoing friendship
-and the role model he has been for me for close to 30 years!
+and for being a role model to me for close to 30 years!
 Having him as a reviewer is an exciting privilege. It has also
 been extremely humbling@enddots{}
 
@@ -2120,14 +2261,14 @@ which they raised and educated me.
 Finally, I also must acknowledge my gratitude to G-d, for the many opportunities
 He has sent my way, as well as for the gifts He has given me with which to
 take advantage of those opportunities.
-@iftex
+@ifnotdocbook
 @sp 2
 @noindent
 Arnold Robbins @*
 Nof Ayalon @*
-ISRAEL @*
-December, 2014
-@end iftex
+Israel @*
+February 2015
+@end ifnotdocbook
 
 @ifnotinfo
 @part @value{PART1}The @command{awk} Language
@@ -2143,31 +2284,31 @@ following chapters:
 
 @itemize @value{BULLET}
 @item
-@ref{Getting Started}.
+@ref{Getting Started}
 
 @item
-@ref{Invoking Gawk}.
+@ref{Invoking Gawk}
 
 @item
-@ref{Regexp}.
+@ref{Regexp}
 
 @item
-@ref{Reading Files}.
+@ref{Reading Files}
 
 @item
-@ref{Printing}.
+@ref{Printing}
 
 @item
-@ref{Expressions}.
+@ref{Expressions}
 
 @item
-@ref{Patterns and Actions}.
+@ref{Patterns and Actions}
 
 @item
-@ref{Arrays}.
+@ref{Arrays}
 
 @item
-@ref{Functions}.
+@ref{Functions}
 @end itemize
 @end ifdocbook
 
@@ -2182,17 +2323,17 @@ following chapters:
 The basic function of @command{awk} is to search files for lines (or other
 units of text) that contain certain patterns.  When a line matches one
 of the patterns, @command{awk} performs specified actions on that line.
-@command{awk} keeps processing input lines in this way until it reaches
+@command{awk} continues to process input lines in this way until it reaches
 the end of the input files.
 
 @cindex @command{awk}, uses for
 @cindex programming languages@comma{} data-driven vs.@: procedural
 @cindex @command{awk} programs
 Programs in @command{awk} are different from programs in most other languages,
-because @command{awk} programs are @dfn{data-driven}; that is, you describe
-the data you want to work with and then what to do when you find it.
+because @command{awk} programs are @dfn{data driven} (i.e., you describe
+the data you want to work with and then what to do when you find it).
 Most other languages are @dfn{procedural}; you have to describe, in great
-detail, every step the program is to take.  When working with procedural
+detail, every step the program should take.  When working with procedural
 languages, it is usually much
 harder to clearly describe the data your program will process.
 For this reason, @command{awk} programs are often refreshingly easy to
@@ -2202,15 +2343,15 @@ read and write.
 @cindex rule, definition of
 When you run @command{awk}, you specify an @command{awk} @dfn{program} that
 tells @command{awk} what to do.  The program consists of a series of
-@dfn{rules}.  (It may also contain @dfn{function definitions},
-an advanced feature that we will ignore for now.
-@xref{User-defined}.)  Each rule specifies one
+@dfn{rules} (it may also contain @dfn{function definitions},
+an advanced feature that we will ignore for now;
+@pxref{User-defined}).  Each rule specifies one
 pattern to search for and one action to perform
 upon finding the pattern.
 
-Syntactically, a rule consists of a pattern followed by an action.  The
-action is enclosed in braces to separate it from the pattern.
-Newlines usually separate rules.  Therefore, an @command{awk}
+Syntactically, a rule consists of a @dfn{pattern} followed by an
+@dfn{action}.  The action is enclosed in braces to separate it from the
+pattern.  Newlines usually separate rules.  Therefore, an @command{awk}
 program looks like this:
 
 @example
@@ -2284,8 +2425,8 @@ awk '@var{program}' @var{input-file1} @var{input-file2} @dots{}
 @end example
 
 @noindent
-where @var{program} consists of a series of @var{patterns} and
-@var{actions}, as described earlier.
+where @var{program} consists of a series of patterns and
+actions, as described earlier.
 
 @cindex single quote (@code{'})
 @cindex @code{'} (single quote)
@@ -2304,11 +2445,12 @@ programs from shell scripts, because it avoids the need for a separate
 file for the @command{awk} program.  A self-contained shell script is more
 reliable because there are no other files to misplace.
 
+Later in this chapter, in
+@ifdocbook
+the section
+@end ifdocbook
 @ref{Very Simple},
-@ifnotinfo
-later in this @value{CHAPTER},
-@end ifnotinfo
-presents several short,
+we'll see examples of several short,
 self-contained programs.
 
 @node Read Terminal
@@ -2329,10 +2471,10 @@ awk '@var{program}'
 which usually means whatever you type on the keyboard.  This continues
 until you indicate end-of-file by typing @kbd{Ctrl-d}.
 @ifset FOR_PRINT
-(On other operating systems, the end-of-file character may be different.)
+(On non-POSIX operating systems, the end-of-file character may be different.)
 @end ifset
 @ifclear FOR_PRINT
-(On other operating systems, the end-of-file character may be different.
+(On non-POSIX operating systems, the end-of-file character may be different.
 For example, on OS/2, it is @kbd{Ctrl-z}.)
 @end ifclear
 
@@ -2366,7 +2508,7 @@ startup file.
 
 This next simple @command{awk} program
 emulates the @command{cat} utility; it copies whatever you type on the
-keyboard to its standard output (why this works is explained shortly).
+keyboard to its standard output (why this works is explained shortly):
 
 @example
 $ @kbd{awk '@{ print @}'}
@@ -2432,11 +2574,9 @@ for programs that are provided on the @command{awk} command line.
 (Also, placing the program in a file allows us to use a literal single quote in the program
 text, instead of the magic @samp{\47}.)
 
-@c STARTOFRANGE sq1x
 @cindex single quote (@code{'}) in @command{gawk} command lines
-@c STARTOFRANGE qs2x
 @cindex @code{'} (single quote) in @command{gawk} command lines
-If you want to clearly identify your @command{awk} program files as such,
+If you want to clearly identify an @command{awk} program file as such,
 you can add the extension @file{.awk} to the @value{FN}.  This doesn't
 affect the execution of the @command{awk} program but it does make
 ``housekeeping'' easier.
@@ -2451,7 +2591,7 @@ affect the execution of the @command{awk} program but it does make
 Once you have learned @command{awk}, you may want to write self-contained
 @command{awk} scripts, using the @samp{#!} script mechanism.  You can do
 this on many systems.@footnote{The @samp{#!} mechanism works on
-GNU/Linux systems, BSD-based systems and commercial Unix systems.}
+GNU/Linux systems, BSD-based systems, and commercial Unix systems.}
 For example, you could update the file @file{advice} to look like this:
 
 @example
@@ -2490,7 +2630,7 @@ according to the instructions in your program. (This is different
 from a @dfn{compiled} language such as C, where your program is first
 compiled into machine code that is executed directly by your system's
 processor.)  The @command{awk} utility is thus termed an @dfn{interpreter}.
-Many modern languages are interperted.
+Many modern languages are interpreted.
 
 The line beginning with @samp{#!} lists the full @value{FN} of an
 interpreter to run and a single optional initial command-line argument
@@ -2536,14 +2676,14 @@ can explain what the program does and how it works.  Nearly all
 programming languages have provisions for comments, as programs are
 typically hard to understand without them.
 
-In the @command{awk} language, a comment starts with the sharp sign
+In the @command{awk} language, a comment starts with the number sign
 character (@samp{#}) and continues to the end of the line.
 The @samp{#} does not have to be the first character on the line. The
-@command{awk} language ignores the rest of a line following a sharp sign.
+@command{awk} language ignores the rest of a line following a number sign.
 For example, we could have put the following into @file{advice}:
 
 @example
-# This program prints a nice friendly message.  It helps
+# This program prints a nice, friendly message.  It helps
 # keep novice users from being afraid of the computer.
 BEGIN    @{ print "Don't Panic!" @}
 @end example
@@ -2559,7 +2699,8 @@ when reading it at a later time.
 @quotation CAUTION
 As mentioned in
 @ref{One-shot},
-you can enclose small to medium programs in single quotes, in order to keep
+you can enclose short to medium-sized programs in single quotes,
+in order to keep
 your shell scripts self-contained.  When doing so, @emph{don't} put
 an apostrophe (i.e., a single quote) into a comment (or anywhere else
 in your program). The shell interprets the quote as the closing
@@ -2588,19 +2729,19 @@ $ @kbd{awk '@{ print "hello" @} # let's be cute'}
 @cindex @code{\} (backslash)
 @cindex backslash (@code{\})
 Putting a backslash before the single quote in @samp{let's} wouldn't help,
-since backslashes are not special inside single quotes.
+because backslashes are not special inside single quotes.
 The next @value{SUBSECTION} describes the shell's quoting rules.
 @end quotation
 
 @node Quoting
-@subsection Shell-Quoting Issues
+@subsection Shell Quoting Issues
 @cindex shell quoting, rules for
 
 @menu
 * DOS Quoting::                 Quoting in Windows Batch Files.
 @end menu
 
-For short to medium length @command{awk} programs, it is most convenient
+For short to medium-length @command{awk} programs, it is most convenient
 to enter the program on the @command{awk} command line.
 This is best done by enclosing the entire program in single quotes.
 This is true whether you are entering the program interactively at
@@ -2624,8 +2765,8 @@ or empty, string.
 The null string is character data that has no value.
 In other words, it is empty.  It is written in @command{awk} programs
 like this: @code{""}. In the shell, it can be written using single
-or double quotes: @code{""} or @code{''}. While the null string has
-no characters in it, it does exist. Consider this command:
+or double quotes: @code{""} or @code{''}. Although the null string has
+no characters in it, it does exist. For example, consider this command:
 
 @example
 $ @kbd{echo ""}
@@ -2635,8 +2776,7 @@ $ @kbd{echo ""}
 Here, the @command{echo} utility receives a single argument, even
 though that argument has no characters in it. In the rest of this
 @value{DOCUMENT}, we use the terms @dfn{null string} and @dfn{empty string}
-interchangeably.  Now, on to the quoting rules.
-
+interchangeably.  Now, on to the quoting rules:
 
 @itemize @value{BULLET}
 @item
@@ -2659,7 +2799,7 @@ The shell does no interpretation of the quoted text, passing it on verbatim
 to the command.
 It is @emph{impossible} to embed a single quote inside single-quoted text.
 Refer back to
-@ref{Comments},
+@DBREF{Comments}
 for an example of what happens if you try.
 
 @item
@@ -2669,7 +2809,7 @@ Double quotes protect most things between the opening and closing quotes.
 The shell does at least variable and command substitution on the quoted text.
 Different shells may do additional kinds of processing on double-quoted text.
 
-Since certain characters within double-quoted text are processed by the shell,
+Because certain characters within double-quoted text are processed by the shell,
 they must be @dfn{escaped} within the text.  Of note are the characters
 @samp{$}, @samp{`}, @samp{\}, and @samp{"}, all of which must be preceded by
 a backslash within double-quoted text if they are to be passed on literally
@@ -2731,7 +2871,7 @@ $ @kbd{awk 'BEGIN @{ print "Here is a single quote <'"'"'>" @}'}
 
 @noindent
 This program consists of three concatenated quoted strings.  The first and the
-third are single-quoted, the second is double-quoted.
+third are single-quoted, and the second is double-quoted.
 
 This can be ``simplified'' to:
 
@@ -2752,8 +2892,6 @@ $ @kbd{awk "BEGIN @{ print \"Here is a single quote <'>\" @}"}
 @end example
 
 @noindent
-@c ENDOFRANGE sq1x
-@c ENDOFRANGE qs2x
 This option is also painful, because double quotes, backslashes, and dollar signs
 are very common in more advanced @command{awk} programs.
 
@@ -2770,22 +2908,22 @@ $ @kbd{awk 'BEGIN @{ print "Here is a double quote <\42>" @}'}
 @end example
 
 @noindent
-This works nicely, except that you should comment clearly what the
+This works nicely, but you should comment clearly what the
 escapes mean.
 
 A fourth option is to use command-line variable assignment, like this:
 
 @example
-$ awk -v sq="'" 'BEGIN @{ print "Here is a single quote <" sq ">" @}'
+$ @kbd{awk -v sq="'" 'BEGIN @{ print "Here is a single quote <" sq ">" @}'}
 @print{} Here is a single quote <'>
 @end example
 
 (Here, the two string constants and the value of @code{sq} are concatenated
-into a single string which is printed by @code{print}.)
+into a single string that is printed by @code{print}.)
 
 If you really need both single and double quotes in your @command{awk}
 program, it is probably best to move it into a separate file, where
-the shell won't be part of the picture, and you can say what you mean.
+the shell won't be part of the picture and you can say what you mean.
 
 @node DOS Quoting
 @subsubsection Quoting in MS-Windows Batch Files
@@ -2847,7 +2985,7 @@ information about monthly shipments.  In both files,
 each line is considered to be one @dfn{record}.
 
 In @file{mail-list}, each record contains the name of a person,
-his/her phone number, his/her email-address, and a code for their relationship
+his/her phone number, his/her email address, and a code for his/her relationship
 with the author of the list.
 The columns are aligned using spaces.
 An @samp{A} in the last column
@@ -2884,7 +3022,7 @@ of green crates shipped, the number of red boxes shipped, the number of
 orange bags shipped, and the number of blue packages shipped,
 respectively.  There are 16 entries, covering the 12 months of last year
 and the first four months of the current year.
-An empty line separates the data for the two years.
+An empty line separates the data for the two years:
 
 @example
 @c file eg/data/inventory-shipped
@@ -2918,7 +3056,7 @@ The following command runs a simple @command{awk} program that searches the
 input file @file{mail-list} for the character string @samp{li} (a
 grouping of characters is usually called a @dfn{string};
 the term @dfn{string} is based on similar usage in English, such
-as ``a string of pearls,'' or ``a string of cars in a train''):
+as ``a string of pearls'' or ``a string of cars in a train''):
 
 @example
 awk '/li/ @{ print $0 @}' mail-list
@@ -2965,11 +3103,11 @@ omitting the @code{print} statement but retaining the braces makes an
 empty action that does nothing (i.e., no lines are printed).
 
 @cindex @command{awk} programs, one-line examples
-Many practical @command{awk} programs are just a line or two.  Following is a
+Many practical @command{awk} programs are just a line or two long.  Following is a
 collection of useful, short programs to get you started.  Some of these
 programs contain constructs that haven't been covered yet. (The description
-of the program will give you a good idea of what is going on, but please
-read the rest of the @value{DOCUMENT} to become an @command{awk} expert!)
+of the program will give you a good idea of what is going on, but you'll
+need to read the rest of the @value{DOCUMENT} to become an @command{awk} expert!)
 Most of the examples use a @value{DF} named @file{data}.  This is just a
 placeholder; if you use these programs yourself, substitute
 your own @value{FN}s for @file{data}.
@@ -2986,7 +3124,7 @@ Print every line that is longer than 80 characters:
 awk 'length($0) > 80' data
 @end example
 
-The sole rule has a relational expression as its pattern and it has no
+The sole rule has a relational expression as its pattern and has no
 action---so it uses the default action, printing the record.
 
 @item
@@ -3010,7 +3148,7 @@ expand data | awk '@{ if (x < length($0)) x = length($0) @}
 @end example
 
 This example differs slightly from the previous one:
-The input is processed by the @command{expand} utility to change TABs
+the input is processed by the @command{expand} utility to change TABs
 into spaces, so the widths compared are actually the right-margin columns,
 as opposed to the number of input characters on each line.
 
@@ -3073,7 +3211,7 @@ Print the even-numbered lines in the @value{DF}:
 awk 'NR % 2 == 0' data
 @end example
 
-If you use the expression @samp{NR % 2 == 1} instead,
+If you used the expression @samp{NR % 2 == 1} instead,
 the program would print the odd-numbered lines.
 @end itemize
 
@@ -3089,8 +3227,13 @@ no actions run.
 
 After processing all the rules that match the line (and perhaps there are none),
 @command{awk} reads the next line.  (However,
-@pxref{Next Statement},
+@DBPXREF{Next Statement}
+@ifdocbook
+and @DBREF{Nextfile Statement}.)
+@end ifdocbook
+@ifnotdocbook
 and also @pxref{Nextfile Statement}.)
+@end ifnotdocbook
 This continues until the program reaches the end of the file.
 For example, the following @command{awk} program contains two rules:
 
@@ -3264,7 +3407,7 @@ lines in the middle of a regular expression or a string.
 with the C shell.}  It works for @command{awk} programs in files and
 for one-shot programs, @emph{provided} you are using a POSIX-compliant
 shell, such as the Unix Bourne shell or Bash.  But the C shell behaves
-differently!  There, you must use two backslashes in a row, followed by
+differently!  There you must use two backslashes in a row, followed by
 a newline.  Note also that when using the C shell, @emph{every} newline
 in your @command{awk} program must be escaped with a backslash. To illustrate:
 
@@ -3305,9 +3448,9 @@ starts a comment, it ignores @emph{everything} on the rest of the
 line. For example:
 
 @example
-$ gawk 'BEGIN @{ print "dont panic" # a friendly \
->                                    BEGIN rule
-> @}'
+$ @kbd{gawk 'BEGIN @{ print "dont panic" # a friendly \}
+> @kbd{                                   BEGIN rule}
+> @kbd{@}'}
 @error{} gawk: cmd. line:2:                BEGIN rule
 @error{} gawk: cmd. line:2:                ^ syntax error
 @end example
@@ -3355,9 +3498,9 @@ performing bit manipulation, for runtime string translation (internationalizatio
 determining the type of a variable,
 and array sorting.
 
-As we develop our presentation of the @command{awk} language, we introduce
+As we develop our presentation of the @command{awk} language, we will introduce
 most of the variables and many of the functions. They are described
-systematically in @ref{Built-in Variables}, and in
+systematically in @DBREF{Built-in Variables} and in
 @ref{Built-in}.
 
 @node When
@@ -3391,8 +3534,8 @@ eight-bit microprocessors,
 @end ifset
 and a microcode assembler for a special-purpose Prolog
 computer.
-While the original @command{awk}'s capabilities were strained by tasks
-of such complexity, modern versions are more capable.
+The original @command{awk}'s capabilities were strained by tasks
+of such complexity, but modern versions are more capable.
 
 @cindex @command{awk} programs, complex
 If you find yourself writing @command{awk} scripts of more than, say,
@@ -3409,7 +3552,7 @@ and Perl.}
 @c FIXME: Review this chapter for summary of builtin functions called.
 @itemize @value{BULLET}
 @item
-Programs in @command{awk} consist of @var{pattern}-@var{action} pairs.
+Programs in @command{awk} consist of @var{pattern}--@var{action} pairs.
 
 @item
 An @var{action} without a @var{pattern} always runs.  The default
@@ -3438,7 +3581,7 @@ part of a larger shell script (or MS-Windows batch file).
 You may use backslash continuation to continue a source line.
 Lines are automatically continued after
 a comma, open brace, question mark, colon,
-@samp{||}, @samp{&&}, @code{do} and @code{else}.
+@samp{||}, @samp{&&}, @code{do}, and @code{else}.
 @end itemize
 
 @node Invoking Gawk
@@ -3447,7 +3590,7 @@ a comma, open brace, question mark, colon,
 This @value{CHAPTER} covers how to run @command{awk}, both POSIX-standard
 and @command{gawk}-specific command-line options, and what
 @command{awk} and
-@command{gawk} do with non-option arguments.
+@command{gawk} do with nonoption arguments.
 It then proceeds to cover how @command{gawk} searches for source files,
 reading standard input along with other files, @command{gawk}'s
 environment variables, @command{gawk}'s exit status, using include files,
@@ -3491,7 +3634,7 @@ enclosed in [@dots{}] in these templates are optional:
 @cindex GNU long options
 @cindex long options
 @cindex options, long
-Besides traditional one-letter POSIX-style options, @command{gawk} also
+In addition to traditional one-letter POSIX-style options, @command{gawk} also
 supports GNU long options.
 
 @cindex dark corner, invoking @command{awk}
@@ -3513,20 +3656,16 @@ warning that the program is empty.
 
 @node Options
 @section Command-Line Options
-@c STARTOFRANGE ocl
 @cindex options, command-line
-@c STARTOFRANGE clo
 @cindex command line, options
-@c STARTOFRANGE gnulo
 @cindex GNU long options
-@c STARTOFRANGE longo
 @cindex options, long
 
 Options begin with a dash and consist of a single character.
 GNU-style long options consist of two dashes and a keyword.
 The keyword can be abbreviated, as long as the abbreviation allows the option
-to be uniquely identified.  If the option takes an argument, then the
-keyword is either immediately followed by an equals sign (@samp{=}) and the
+to be uniquely identified.  If the option takes an argument, either the
+keyword is immediately followed by an equals sign (@samp{=}) and the
 argument's value, or the keyword and the argument's value are separated
 by whitespace.
 If a particular option with a value is given more than once, it is the
@@ -3553,8 +3692,8 @@ Set the @code{FS} variable to @var{fs}
 @cindex @option{-f} option
 @cindex @option{--file} option
 @cindex @command{awk} programs, location of
-Read @command{awk} program source from @var{source-file}
-instead of in the first non-option argument.
+Read the @command{awk} program source from @var{source-file}
+instead of in the first nonoption argument.
 This option may be given multiple times; the @command{awk}
 program consists of the concatenation of the contents of
 each specified @var{source-file}.
@@ -3608,8 +3747,6 @@ by the user that could start with @samp{-}.
 It is also useful for passing options on to the @command{awk}
 program; see @ref{Getopt Function}.
 @end table
-@c ENDOFRANGE gnulo
-@c ENDOFRANGE longo
 
 The following list describes @command{gawk}-specific options:
 
@@ -3621,14 +3758,14 @@ The following list describes @command{gawk}-specific options:
 @cindex @option{--characters-as-bytes} option
 Cause @command{gawk} to treat all input data as single-byte characters.
 In addition, all output written with @code{print} or @code{printf}
-are treated as single-byte characters.
+is treated as single-byte characters.
 
 Normally, @command{gawk} follows the POSIX standard and attempts to process
 its input data according to the current locale (@pxref{Locales}). This can often involve
 converting multibyte characters into wide characters (internally), and
 can lead to problems or confusion if the input data does not contain valid
-multibyte characters. This option is an easy way to tell @command{gawk}:
-``hands off my data!''.
+multibyte characters. This option is an easy way to tell @command{gawk},
+``Hands off my data!''
 
 @item @option{-c}
 @itemx @option{--traditional}
@@ -3682,9 +3819,10 @@ names like @code{i}, @code{j}, etc.)
 @cindex @command{awk} debugging, enabling
 Enable debugging of @command{awk} programs
 (@pxref{Debugging}).
-By default, the debugger reads commands interactively from the keyboard.
+By default, the debugger reads commands interactively from the keyboard
+(standard input).
 The optional @var{file} argument allows you to specify a file with a list
-of commands for the debugger to execute non-interactively.
+of commands for the debugger to execute noninteractively.
 No space is allowed between the @option{-D} and @var{file}, if
 @var{file} is supplied.
 
@@ -3722,7 +3860,13 @@ Command-line variable assignments of the form
 This option is particularly necessary for World Wide Web CGI applications
 that pass arguments through the URL; using this option prevents a malicious
 (or other) user from passing in options, assignments, or @command{awk} source
-code (via @option{-e}) to the CGI application.  This option should be used
+code (via @option{-e}) to the CGI application.@footnote{For more detail,
+please see Section 4.4 of @uref{http://www.ietf.org/rfc/rfc3875,
+RFC 3875}. Also see the
+@uref{http://lists.gnu.org/archive/html/bug-gawk/2014-11/msg00022.html,
+explanatory note sent to the @command{gawk} bug
+mailing list}.}
+This option should be used
 with @samp{#!} scripts (@pxref{Executable Scripts}), like so:
 
 @example
@@ -3738,7 +3882,7 @@ with @samp{#!} scripts (@pxref{Executable Scripts}), like so:
 @cindex portable object files, generating
 @cindex files, portable object, generating
 Analyze the source program and
-generate a GNU @command{gettext} Portable Object Template file on standard
+generate a GNU @command{gettext} portable object template file on standard
 output for all string constants that have been marked for translation.
 @xref{Internationalization},
 for information about this option.
@@ -3750,7 +3894,7 @@ for information about this option.
 @cindex GNU long options, printing list of
 @cindex options, printing list of
 @cindex printing, list of options
-Print a ``usage'' message summarizing the short and long style options
+Print a ``usage'' message summarizing the short- and long-style options
 that @command{gawk} accepts and then exit.
 
 @item @option{-i} @var{source-file}
@@ -3760,7 +3904,7 @@ that @command{gawk} accepts and then exit.
 @cindex @command{awk} programs, location of
 Read an @command{awk} source library from @var{source-file}.  This option
 is completely equivalent to using the @code{@@include} directive inside
-your program.  This option is very similar to the @option{-f} option,
+your program.  It is very similar to the @option{-f} option,
 but there are two important differences.  First, when @option{-i} is
 used, the program source is not loaded if it has been previously
 loaded, whereas with @option{-f}, @command{gawk} always loads the file.
@@ -3813,7 +3957,7 @@ care to search for all occurrences of each inappropriate construct. As
 @itemx @option{--bignum}
 @cindex @option{-M} option
 @cindex @option{--bignum} option
-Force arbitrary precision arithmetic on numbers. This option has no effect
+Force arbitrary-precision arithmetic on numbers. This option has no effect
 if @command{gawk} is not compiled to use the GNU MPFR and MP libraries
 (@pxref{Arbitrary Precision Arithmetic}).
 
@@ -3829,10 +3973,8 @@ values in input data
 (@pxref{Nondecimal Data}).
 
 @quotation CAUTION
-This option can severely break old programs.
-Use with care.
-
-This option may disappear in a future version of @command{gawk}.
+This option can severely break old programs.  Use with care.  Also note
+that this option may disappear in a future version of @command{gawk}.
 @end quotation
 
 @item @option{-N}
@@ -3847,7 +3989,7 @@ when parsing numeric input data (@pxref{Locales}).
 @cindex @option{-o} option
 @cindex @option{--pretty-print} option
 Enable pretty-printing of @command{awk} programs.
-By default, output program is created in a file named @file{awkprof.out}
+By default, the output program is created in a file named @file{awkprof.out}
 (@pxref{Profiling}).
 The optional @var{file} argument allows you to specify a different
 @value{FN} for the output.
@@ -3864,7 +4006,7 @@ This is no longer the case.
 @cindex @option{--optimize} option
 @cindex @option{-O} option
 Enable some optimizations on the internal representation of the program.
-At the moment this includes just simple constant folding.
+At the moment, this includes just simple constant folding.
 
 @item @option{-p}[@var{file}]
 @itemx @option{--profile}[@code{=}@var{file}]
@@ -3891,7 +4033,7 @@ in the left margin, and function call counts for each function.
 Operate in strict POSIX mode.  This disables all @command{gawk}
 extensions (just like @option{--traditional}) and
 disables all extensions not allowed by POSIX.
-@xref{Common Extensions}, for a summary of the extensions
+@DBXREF{Common Extensions} for a summary of the extensions
 in @command{gawk} that are disabled by this option.
 Also,
 the following additional
@@ -3941,8 +4083,8 @@ Allow interval expressions
 (@pxref{Regexp Operators})
 in regexps.
 This is now @command{gawk}'s default behavior.
-Nevertheless, this option remains both for backward compatibility,
-and for use in combination with @option{--traditional}.
+Nevertheless, this option remains (both for backward compatibility
+and for use in combination with @option{--traditional}).
 
 @item @option{-S}
 @itemx @option{--sandbox}
@@ -3995,7 +4137,7 @@ If it is, @command{awk} reads its program source from all of the named files, as
 if they had been concatenated together into one big file.  This is
 useful for creating libraries of @command{awk} functions.  These functions
 can be written once and then retrieved from a standard place, instead
-of having to be included into each individual program.
+of having to be included in each individual program.
 The @option{-i} option is similar in this regard.
 (As mentioned in
 @ref{Definition Syntax},
@@ -4006,20 +4148,20 @@ if the program is entered at the keyboard,
 by specifying @samp{-f /dev/tty}.  After typing your program,
 type @kbd{Ctrl-d} (the end-of-file character) to terminate it.
 (You may also use @samp{-f -} to read program source from the standard
-input but then you will not be able to also use the standard input as a
+input, but then you will not be able to also use the standard input as a
 source of data.)
 
 Because it is clumsy using the standard @command{awk} mechanisms to mix
 source file and command-line @command{awk} programs, @command{gawk}
 provides the @option{-e} option.  This does not require you to
-pre-empt the standard input for your source code; it allows you to easily
+preempt the standard input for your source code; it allows you to easily
 mix command-line and library source code (@pxref{AWKPATH Variable}).
 As with @option{-f}, the @option{-e} and @option{-i}
 options may also be used multiple times on the command line.
 
 @cindex @option{-e} option
 If no @option{-f} or @option{-e} option is specified, then @command{gawk}
-uses the first non-option command-line argument as the text of the
+uses the first nonoption command-line argument as the text of the
 program source code.
 
 @cindex @env{POSIXLY_CORRECT} environment variable
@@ -4058,8 +4200,6 @@ setenv POSIXLY_CORRECT true
 Having @env{POSIXLY_CORRECT} set is not recommended for daily use,
 but it is good for testing the portability of your programs to other
 environments.
-@c ENDOFRANGE ocl
-@c ENDOFRANGE clo
 
 @node Other Arguments
 @section Other Command-Line Arguments
@@ -4086,7 +4226,7 @@ All the command-line arguments are made available to your @command{awk} program
 and the program text (if present) are omitted from @code{ARGV}.
 All other arguments, including variable assignments, are
 included.   As each element of @code{ARGV} is processed, @command{gawk}
-sets the variable @code{ARGIND} to the index in @code{ARGV} of the
+sets @code{ARGIND} to the index in @code{ARGV} of the
 current element.
 
 @c FIXME: One day, move the ARGC and ARGV node closer to here.
@@ -4191,30 +4331,26 @@ behaves.
 @cindex @env{AWKPATH} environment variable
 @cindex directories, searching for source files
 @cindex search paths, for source files
-@cindex differences in @command{awk} and @command{gawk}, @code{AWKPATH} environment variable
+@cindex differences in @command{awk} and @command{gawk}, @env{AWKPATH} environment variable
 @ifinfo
 The previous @value{SECTION} described how @command{awk} program files can be named
 on the command line with the @option{-f} option.
 @end ifinfo
 In most @command{awk}
-implementations, you must supply a precise path name for each program
+implementations, you must supply a precise pathname for each program
 file, unless the file is in the current directory.
-But in @command{gawk}, if the @value{FN} supplied to the @option{-f}
+But with @command{gawk}, if the @value{FN} supplied to the @option{-f}
 or @option{-i} options
 does not contain a directory separator @samp{/}, then @command{gawk} searches a list of
-directories (called the @dfn{search path}), one by one, looking for a
+directories (called the @dfn{search path}) one by one, looking for a
 file with the specified name.
 
 The search path is a string consisting of directory names
-separated by colons@footnote{Semicolons on MS-Windows and MS-DOS.}.  @command{gawk} gets its search path from the
+separated by colons.@footnote{Semicolons on MS-Windows and MS-DOS.}
+@command{gawk} gets its search path from the
 @env{AWKPATH} environment variable.  If that variable does not exist,
-@command{gawk} uses a default path,
-@samp{.:/usr/local/share/awk}.@footnote{Your version of @command{gawk}
-may use a different directory; it
-will depend upon how @command{gawk} was built and installed. The actual
-directory is the value of @code{$(datadir)} generated when
-@command{gawk} was configured.  You probably don't need to worry about this,
-though.}
+or if it has an empty value,
+@command{gawk} uses a default path (described shortly).
 
 The search path feature is particularly helpful for building libraries
 of useful @command{awk} functions.  The library files can be placed in a
@@ -4222,7 +4358,7 @@ standard directory in the default path and then specified on
 the command line with a short @value{FN}.  Otherwise, you would have to
 type the full @value{FN} for each file.
 
-By using the @option{-i} option, or the @option{-e} and @option{-f} options, your command-line
+By using the @option{-i} or @option{-f} options, your command-line
 @command{awk} programs can use facilities in @command{awk} library files
 (@pxref{Library Functions}).
 Path searching is not done if @command{gawk} is in compatibility mode.
@@ -4230,7 +4366,7 @@ This is true for both @option{--traditional} and @option{--posix}.
 @xref{Options}.
 
 If the source code file is not found after the initial search, the path is searched
-again after adding the default @samp{.awk} suffix to the @value{FN}.
+again after adding the suffix @samp{.awk} to the @value{FN}.
 
 @command{gawk}'s path search mechanism is similar
 to the shell's.
@@ -4242,21 +4378,35 @@ directory.
 colon or by placing two colons next to each other [@samp{::}].)
 
 @quotation NOTE
-@command{gawk} always looks in the current directory @emph{before}
-searching @env{AWKPATH}. Thus, while you can include the current directory
-in the search path, either explicitly or with a null entry, there is no
-real reason to do so.
-@c Prior to 4.0, gawk searched the current directory after the
-@c path search, but it's not worth documenting it.
+To include the current directory in the path, either place @file{.}
+as an entry in the path or write a null entry in the path.
+
+Different past versions of @command{gawk} would also look explicitly in
+the current directory, either before or after the path search.  As of
+@value{PVERSION} 4.1.2, this no longer happens; if you wish to look
+in the current directory, you must include @file{.} either as a separate
+entry or as a null entry in the search path.
 @end quotation
 
-If @env{AWKPATH} is not defined in the
-environment, @command{gawk} places its default search path into
-@code{ENVIRON["AWKPATH"]}. This makes it easy to determine
-the actual search path that @command{gawk} used
-from within an @command{awk} program.
+The default value for @env{AWKPATH} is
+@samp{.:/usr/local/share/awk}.@footnote{Your version of @command{gawk}
+may use a different directory; it
+will depend upon how @command{gawk} was built and installed. The actual
+directory is the value of @code{$(datadir)} generated when
+@command{gawk} was configured.  You probably don't need to worry about this,
+though.}  Since @file{.} is included at the beginning, @command{gawk}
+searches first in the current directory and then in @file{/usr/local/share/awk}.
+In practice, this means that you will rarely need to change the
+value of @env{AWKPATH}.
 
-While you can change @code{ENVIRON["AWKPATH"]} within your @command{awk}
+@xref{Shell Startup Files}, for information on functions that help to
+manipulate the @env{AWKPATH} variable.
+
+@command{gawk} places the value of the search path that it used into
+@code{ENVIRON["AWKPATH"]}. This provides access to the actual search
+path value from within an @command{awk} program.
+
+Although you can change @code{ENVIRON["AWKPATH"]} within your @command{awk}
 program, this has no effect on the running program's behavior.  This makes
 sense: the @env{AWKPATH} environment variable is used to find the program
 source files.  Once your program is running, all the files have been
@@ -4278,12 +4428,24 @@ the platform.  For example, on GNU/Linux systems, the suffix @samp{.so}
 is used.  The search path specified is also used for extensions loaded
 via the @code{@@load} keyword (@pxref{Loading Shared Libraries}).
 
+If @env{AWKLIBPATH} does not exist in the environment, or if it has
+an empty value, @command{gawk} uses a default path; this
+is typically @samp{/usr/local/lib/gawk}, although it can vary depending
+upon how @command{gawk} was built.
+
+@xref{Shell Startup Files}, for information on functions that help to
+manipulate the @env{AWKLIBPATH} variable.
+
+@command{gawk} places the value of the search path that it used into
+@code{ENVIRON["AWKLIBPATH"]}. This provides access to the actual search
+path value from within an @command{awk} program.
+
 @node Other Environment Variables
 @subsection Other Environment Variables
 
 A number of other environment variables affect @command{gawk}'s
 behavior, but they are more specialized. Those in the following
-list are meant to be used by regular users.
+list are meant to be used by regular users:
 
 @table @env
 @item GAWK_MSEC_SLEEP
@@ -4301,9 +4463,11 @@ wait for input before returning with an error.
 Controls the number of times @command{gawk} attempts to
 retry a two-way TCP/IP (socket) connection before giving up.
 @xref{TCP/IP Networking}.
+Note that when nonfatal I/O is enabled (@pxref{Nonfatal}),
+@command{gawk} only tries to open a TCP/IP socket once.
 
 @item POSIXLY_CORRECT
-Causes @command{gawk} to switch to POSIX compatibility
+Causes @command{gawk} to switch to POSIX-compatibility
 mode, disabling all traditional and GNU extensions.
 @xref{Options}.
 @end table
@@ -4335,11 +4499,11 @@ for debugging problems on filesystems on non-POSIX operating systems
 where I/O is performed in records, not in blocks.
 
 @item GAWK_MSG_SRC
-If this variable exists, @command{gawk} includes the file
-name and line number within the @command{gawk} source code
+If this variable exists, @command{gawk} includes the @value{FN}
+and line number within the @command{gawk} source code
 from which warning and/or fatal messages
 are generated.  Its purpose is to help isolate the source of a
-message, since there are multiple places which produce the
+message, as there are multiple places that produce the
 same warning or error message.
 
 @item GAWK_NO_DFA
@@ -4355,16 +4519,16 @@ This specifies the amount by which @command{gawk} should grow its
 internal evaluation stack, when needed.
 
 @item INT_CHAIN_MAX
-The intended maximum number of items @command{gawk} will maintain on a
+This specifies intended maximum number of items @command{gawk} will maintain on a
 hash chain for managing arrays indexed by integers.
 
 @item STR_CHAIN_MAX
-The intended maximum number of items @command{gawk} will maintain on a
+This specifies intended maximum number of items @command{gawk} will maintain on a
 hash chain for managing arrays indexed by strings.
 
 @item TIDYMEM
 If this variable exists, @command{gawk} uses the @code{mtrace()} library
-calls from GNU LIBC to help track down possible memory leaks.
+calls from the GNU C library to help track down possible memory leaks.
 @end table
 
 @node Exit Status
@@ -4383,11 +4547,11 @@ If an error occurs, @command{gawk} exits with the value of
 the C constant @code{EXIT_FAILURE}.  This is usually one.
 
 If @command{gawk} exits because of a fatal error, the exit
-status is 2.  On non-POSIX systems, this value may be mapped
+status is two.  On non-POSIX systems, this value may be mapped
 to @code{EXIT_FAILURE}.
 
 @node Include Files
-@section Including Other Files Into Your Program
+@section Including Other Files into Your Program
 
 @c Panos Papadopoulos <panos1962@gmail.com> contributed the original
 @c text for this section.
@@ -4401,7 +4565,7 @@ The @code{@@include} keyword can be used to read external @command{awk} source
 files.  This gives you the ability to split large @command{awk} source files
 into smaller, more manageable pieces, and also lets you reuse common @command{awk}
 code from various @command{awk} scripts.  In other words, you can group
-together @command{awk} functions, used to carry out specific tasks,
+together @command{awk} functions used to carry out specific tasks
 into external files. These files can be used just like function libraries,
 using the @code{@@include} keyword in conjunction with the @env{AWKPATH}
 environment variable.  Note that source files may also be included
@@ -4436,9 +4600,9 @@ $ @kbd{gawk -f test2}
 @print{} This is script test2.
 @end example
 
-@code{gawk} runs the @file{test2} script which includes @file{test1}
+@command{gawk} runs the @file{test2} script, which includes @file{test1}
 using the @code{@@include}
-keyword.  So, to include external @command{awk} source files you just
+keyword.  So, to include external @command{awk} source files, you just
 use @code{@@include} followed by the name of the file to be included,
 enclosed in double quotes.
 
@@ -4475,27 +4639,28 @@ The @value{FN} can, of course, be a pathname. For example:
 @end example
 
 @noindent
-or:
+and:
 
 @example
 @@include "/usr/awklib/network"
 @end example
 
 @noindent
-are valid. The @code{AWKPATH} environment variable can be of great
+are both valid. The @env{AWKPATH} environment variable can be of great
 value when using @code{@@include}. The same rules for the use
-of the @code{AWKPATH} variable in command-line file searches
+of the @env{AWKPATH} variable in command-line file searches
 (@pxref{AWKPATH Variable}) apply to
 @code{@@include} also.
 
 This is very helpful in constructing @command{gawk} function libraries.
-If you have a large script with useful, general purpose @command{awk}
+If you have a large script with useful, general-purpose @command{awk}
 functions, you can break it down into library files and put those files
-in a special directory.  You can then include those ``libraries,'' using
-either the full pathnames of the files, or by setting the @code{AWKPATH}
+in a special directory.  You can then include those ``libraries,''
+either by using the full pathnames of the files, or by setting the @env{AWKPATH}
 environment variable accordingly and then using @code{@@include} with
-just the file part of the full pathname. Of course you can have more
-than one directory to keep library files; the more complex the working
+just the file part of the full pathname. Of course,
+you can keep library files in more than one directory;
+the more complex the working
 environment is, the more directories you may need to organize the files
 to be included.
 
@@ -4508,11 +4673,11 @@ In particular, @code{@@include} is very useful for writing CGI scripts
 to be run from web pages.
 
 As mentioned in @ref{AWKPATH Variable}, the current directory is always
-searched first for source files, before searching in @env{AWKPATH},
-and this also applies to files named with @code{@@include}.
+searched first for source files, before searching in @env{AWKPATH};
+this also applies to files named with @code{@@include}.
 
 @node Loading Shared Libraries
-@section Loading Dynamic Extensions Into Your Program
+@section Loading Dynamic Extensions into Your Program
 
 This @value{SECTION} describes a feature that is specific to @command{gawk}.
 
@@ -4522,7 +4687,7 @@ This @value{SECTION} describes a feature that is specific to @command{gawk}.
 The @code{@@load} keyword can be used to read external @command{awk} extensions
 (stored as system shared libraries).
 This allows you to link in compiled code that may offer superior
-performance and/or give you access to extended capabilities not supported 
+performance and/or give you access to extended capabilities not supported
 by the @command{awk} language.  The @env{AWKLIBPATH} variable is used to
 search for the extension.  Using @code{@@load} is completely equivalent
 to using the @option{-l} command-line option.
@@ -4530,7 +4695,7 @@ to using the @option{-l} command-line option.
 If the extension is not initially found in @env{AWKLIBPATH}, another
 search is conducted after appending the platform's default shared library
 suffix to the @value{FN}.  For example, on GNU/Linux systems, the suffix
-@samp{.so} is used.
+@samp{.so} is used:
 
 @example
 $ @kbd{gawk '@@load "ordchr"; BEGIN @{print chr(65)@}'}
@@ -4563,8 +4728,8 @@ It also describes the @code{ordchr} extension.
 @cindex features, deprecated
 @cindex obsolete features
 This @value{SECTION} describes features and/or command-line options from
-previous releases of @command{gawk} that are either not available in the
-current version or that are still supported but deprecated (meaning that
+previous releases of @command{gawk} that either are not available in the
+current version or are still supported but deprecated (meaning that
 they will @emph{not} be in the next release).
 
 The process-related special files @file{/dev/pid}, @file{/dev/ppid},
@@ -4644,7 +4809,7 @@ This seems to have been a long-undocumented feature in Unix @command{awk}.
 
 Similarly, you may use @code{print} or @code{printf} statements in the
 @var{init} and @var{increment} parts of a @code{for} loop.  This is another
-long-undocumented ``feature'' of Unix @code{awk}.
+long-undocumented ``feature'' of Unix @command{awk}.
 
 @end ignore
 
@@ -4661,17 +4826,17 @@ to run @command{awk}.
 
 @item
 The three standard options for all versions of @command{awk} are
-@option{-f}, @option{-F} and @option{-v}.  @command{gawk} supplies these
+@option{-f}, @option{-F}, and @option{-v}.  @command{gawk} supplies these
 and many others, as well as corresponding GNU-style long options.
 
 @item
-Non-option command-line arguments are usually treated as @value{FN}s,
+Nonoption command-line arguments are usually treated as @value{FN}s,
 unless they have the form @samp{@var{var}=@var{value}}, in which case
 they are taken as variable assignments to be performed at that point
 in processing the input.
 
 @item
-All non-option command-line arguments, excluding the program text,
+All nonoption command-line arguments, excluding the program text,
 are placed in the @code{ARGV} array.  Adjusting @code{ARGC} and @code{ARGV}
 affects how @command{awk} processes input.
 
@@ -4698,13 +4863,12 @@ and @option{-f} command-line options.
 @item
 @command{gawk} allows you to load additional functions written in C
 or C++ using the @code{@@load} statement and/or the @option{-l} option.
-(This advanced feature is described later on in @ref{Dynamic Extensions}.)
+(This advanced feature is described later, in @ref{Dynamic Extensions}.)
 @end itemize
 
 @node Regexp
 @chapter Regular Expressions
 @cindex regexp
-@c STARTOFRANGE regexp
 @cindex regular expressions
 
 A @dfn{regular expression}, or @dfn{regexp}, is a way of describing a
@@ -4720,7 +4884,7 @@ belongs to that set.
 The simplest regular expression is a sequence of letters, numbers, or
 both.  Such a regexp matches any string that contains that sequence.
 Thus, the regexp @samp{foo} matches any string containing @samp{foo}.
-Therefore, the pattern @code{/foo/} matches any input record containing
+Thus, the pattern @code{/foo/} matches any input record containing
 the three adjacent characters @samp{foo} @emph{anywhere} in the record.  Other
 kinds of regexps let you specify more complicated classes of strings.
 
@@ -4783,17 +4947,16 @@ and @samp{!~} perform regular expression comparisons.  Expressions
 using these operators can be used as patterns, or in @code{if},
 @code{while}, @code{for}, and @code{do} statements.
 (@xref{Statements}.)
-For example:
+For example, the following is true if the expression @var{exp} (taken
+as a string) matches @var{regexp}:
 
 @example
 @var{exp} ~ /@var{regexp}/
 @end example
 
 @noindent
-is true if the expression @var{exp} (taken as a string)
-matches @var{regexp}.  The following example matches, or selects,
-all input records with the uppercase letter @samp{J} somewhere in the
-first field:
+This example matches, or selects, all input records with the uppercase
+letter @samp{J} somewhere in the first field:
 
 @example
 $ @kbd{awk '$1 ~ /J/' inventory-shipped}
@@ -4863,9 +5026,9 @@ string or regexp.  Thus, the string whose contents are the two characters
 @samp{"} and @samp{\} must be written @code{"\"\\"}.
 
 Other escape sequences represent unprintable characters
-such as TAB or newline.  While there is nothing to stop you from entering most
+such as TAB or newline.  There is nothing to stop you from entering most
 unprintable characters directly in a string constant or regexp constant,
-they may look ugly.
+but they may look ugly.
 
 The following list presents
 all the escape sequences used in @command{awk} and
@@ -4912,7 +5075,7 @@ Horizontal TAB, @kbd{Ctrl-i}, ASCII code 9 (HT).
 @cindex @code{\} (backslash), @code{\v} escape sequence
 @cindex backslash (@code{\}), @code{\v} escape sequence
 @item \v
-Vertical tab, @kbd{Ctrl-k}, ASCII code 11 (VT).
+Vertical TAB, @kbd{Ctrl-k}, ASCII code 11 (VT).
 
 @cindex @code{\} (backslash), @code{\}@var{nnn} escape sequence
 @cindex backslash (@code{\}), @code{\}@var{nnn} escape sequence
@@ -4933,15 +5096,18 @@ of hexadecimal digits (@samp{0}--@samp{9}, and either @samp{A}--@samp{F}
 or @samp{a}--@samp{f}).  A maximum of two digts are allowed after
 the @samp{\x}. Any further hexadecimal digits are treated as simple
 letters or numbers.  @value{COMMONEXT}
+(The @samp{\x} escape sequence is not allowed in POSIX awk.)
 
 @quotation CAUTION
 In ISO C, the escape sequence continues until the first nonhexadecimal
 digit is seen.
-@c FIXME: Add exact version here.
 For many years, @command{gawk} would continue incorporating
 hexadecimal digits into the value until a non-hexadecimal digit
 or the end of the string was encountered.
-However, using more than two hexadecimal digits produces
+However, using more than two hexadecimal digits produced
+undefined results.
+As of @value{PVERSION} 4.2, only two digits
+are processed.
 @end quotation
 
 @cindex @code{\} (backslash), @code{\/} escape sequence
@@ -4951,7 +5117,7 @@ A literal slash (necessary for regexp constants only).
 This sequence is used when you want to write a regexp
 constant that contains a slash
 (such as @code{/.*:\/home\/[[:alnum:]]+:.*/}; the @samp{[[:alnum:]]}
-notation is discussed shortly, in @ref{Bracket Expressions}).
+notation is discussed in @ref{Bracket Expressions}).
 Because the regexp is delimited by
 slashes, you need to escape any slash that is part of the pattern,
 in order to tell @command{awk} to keep processing the rest of the regexp.
@@ -4974,7 +5140,7 @@ with a backslash have special meaning in regexps.
 
 In a regexp, a backslash before any character that is not in the previous list
 and not listed in
-@ref{GNU Regexp Operators},
+@DBREF{GNU Regexp Operators}
 means that the next character should be taken literally, even if it would
 normally be a regexp operator.  For example, @code{/a\+b/} matches the three
 characters @samp{a+b}.
@@ -4983,27 +5149,9 @@ characters @samp{a+b}.
 @cindex @code{\} (backslash), in escape sequences
 @cindex portability
 For complete portability, do not use a backslash before any character not
-shown in the previous list and that is not an operator.
-
-To summarize:
-
-@itemize @value{BULLET}
-@item
-The escape sequences in the list above are always processed first,
-for both string constants and regexp constants. This happens very early,
-as soon as @command{awk} reads your program.
-
-@item
-@command{gawk} processes both regexp constants and dynamic regexps
-(@pxref{Computed Regexps}),
-for the special operators listed in
-@ref{GNU Regexp Operators}.
-
-@item
-A backslash before any other character means to treat that character
-literally.
-@end itemize
+shown in the previous list or that is not an operator.
 
+@c 11/2014: Moved so as to not stack sidebars
 @sidebar Backslash Before Regular Characters
 @cindex portability, backslash in escape sequences
 @cindex POSIX @command{awk}, backslashes in string constants
@@ -5039,6 +5187,25 @@ In such implementations, typing @code{"a\qc"} is the same as typing
 @end table
 @end sidebar
 
+To summarize:
+
+@itemize @value{BULLET}
+@item
+The escape sequences in the preceding list are always processed first,
+for both string constants and regexp constants. This happens very early,
+as soon as @command{awk} reads your program.
+
+@item
+@command{gawk} processes both regexp constants and dynamic regexps
+(@pxref{Computed Regexps}),
+for the special operators listed in
+@ref{GNU Regexp Operators}.
+
+@item
+A backslash before any other character means to treat that character
+literally.
+@end itemize
+
 @sidebar Escape Sequences for Metacharacters
 @cindex metacharacters, escape sequences for
 
@@ -5061,7 +5228,6 @@ escape sequences literally when used in regexp constants. Thus,
 
 @node Regexp Operators
 @section Regular Expression Operators
-@c STARTOFRANGE regexpo
 @cindex regular expressions, operators
 @cindex metacharacters in regular expressions
 
@@ -5079,14 +5245,14 @@ are recognized and converted into corresponding real characters as
 the very first step in processing regexps.
 
 Here is a list of metacharacters.  All characters that are not escape
-sequences and that are not listed in the following stand for themselves:
+sequences and that are not listed here stand for themselves:
 
 @c Use @asis so the docbook comes out ok. Sigh.
 @table @asis
 @cindex backslash (@code{\}), regexp operator
 @cindex @code{\} (backslash), regexp operator
 @item @code{\}
-This is used to suppress the special meaning of a character when
+This suppresses the special meaning of a character when
 matching.  For example, @samp{\$}
 matches the character @samp{$}.
 
@@ -5095,8 +5261,9 @@ matches the character @samp{$}.
 @cindex @code{^} (caret), regexp operator
 @cindex caret (@code{^}), regexp operator
 @item @code{^}
-This matches the beginning of a string.  For example, @samp{^@@chapter}
-matches @samp{@@chapter} at the beginning of a string and can be used
+This matches the beginning of a string.  @samp{^@@chapter}
+matches @samp{@@chapter} at the beginning of a string,
+for example, and can be used
 to identify chapter beginnings in Texinfo source files.
 The @samp{^} is known as an @dfn{anchor}, because it anchors the pattern to
 match only at the beginning of the string.
@@ -5136,10 +5303,10 @@ with @samp{A}.
 
 @cindex POSIX @command{awk}, period (@code{.})@comma{} using
 In strict POSIX mode (@pxref{Options}),
-@samp{.} does not match the @value{NUL}
+@samp{.} does not match the @sc{nul}
 character, which is a character with all bits equal to zero.
-Otherwise, @value{NUL} is just another character. Other versions of @command{awk}
-may not be able to match the @value{NUL} character.
+Otherwise, @sc{nul} is just another character. Other versions of @command{awk}
+may not be able to match the @sc{nul} character.
 
 @cindex @code{[]} (square brackets), regexp operator
 @cindex square brackets (@code{[]}), regexp operator
@@ -5201,8 +5368,8 @@ just @samp{p} if no @samp{h}s are present.
 There are two subtle points to understand about how @samp{*} works.
 First, the @samp{*} applies only to the single preceding regular expression
 component (e.g., in @samp{ph*}, it applies just to the @samp{h}).
-To cause @samp{*} to apply to a larger sub-expression, use parentheses:
-@samp{(ph)*} matches @samp{ph}, @samp{phph}, @samp{phphph} and so on.
+To cause @samp{*} to apply to a larger subexpression, use parentheses:
+@samp{(ph)*} matches @samp{ph}, @samp{phph}, @samp{phphph}, and so on.
 
 Second, @samp{*} finds as many repetitions as possible. If the text
 to be matched is @samp{phhhhhhhhhhhhhhooey}, @samp{ph*} matches all of
@@ -5240,10 +5407,10 @@ is repeated at least @var{n} times:
 Matches @samp{whhhy}, but not @samp{why} or @samp{whhhhy}.
 
 @item wh@{3,5@}y
-Matches @samp{whhhy}, @samp{whhhhy}, or @samp{whhhhhy}, only.
+Matches @samp{whhhy}, @samp{whhhhy}, or @samp{whhhhhy} only.
 
 @item wh@{2,@}y
-Matches @samp{whhy} or @samp{whhhy}, and so on.
+Matches @samp{whhy}, @samp{whhhy}, and so on.
 @end table
 
 @cindex POSIX @command{awk}, interval expressions in
@@ -5292,17 +5459,15 @@ usage as a syntax error.
 
 If @command{gawk} is in compatibility mode (@pxref{Options}), interval
 expressions are not available in regular expressions.
-@c ENDOFRANGE regexpo
 
 @node Bracket Expressions
 @section Using Bracket Expressions
-@c STARTOFRANGE charlist
 @cindex bracket expressions
 @cindex bracket expressions, range expressions
 @cindex range expressions (regexps)
 @cindex character lists in regular expression
 
-As mentioned earlier, a bracket expression matches any character amongst
+As mentioned earlier, a bracket expression matches any character among
 those listed between the opening and closing square brackets.
 
 Within a bracket expression, a @dfn{range expression} consists of two
@@ -5360,23 +5525,23 @@ a keyword denoting the class, and @samp{:]}.
 POSIX standard.
 
 @float Table,table-char-classes
-@caption{POSIX Character Classes}
+@caption{POSIX character classes}
 @multitable @columnfractions .15 .85
 @headitem Class @tab Meaning
-@item @code{[:alnum:]} @tab Alphanumeric characters.
-@item @code{[:alpha:]} @tab Alphabetic characters.
-@item @code{[:blank:]} @tab Space and TAB characters.
-@item @code{[:cntrl:]} @tab Control characters.
-@item @code{[:digit:]} @tab Numeric characters.
-@item @code{[:graph:]} @tab Characters that are both printable and visible.
-(A space is printable but not visible, whereas an @samp{a} is both.)
-@item @code{[:lower:]} @tab Lowercase alphabetic characters.
-@item @code{[:print:]} @tab Printable characters (characters that are not control characters).
+@item @code{[:alnum:]} @tab Alphanumeric characters
+@item @code{[:alpha:]} @tab Alphabetic characters
+@item @code{[:blank:]} @tab Space and TAB characters
+@item @code{[:cntrl:]} @tab Control characters
+@item @code{[:digit:]} @tab Numeric characters
+@item @code{[:graph:]} @tab Characters that are both printable and visible
+(a space is printable but not visible, whereas an @samp{a} is both)
+@item @code{[:lower:]} @tab Lowercase alphabetic characters
+@item @code{[:print:]} @tab Printable characters (characters that are not control characters)
 @item @code{[:punct:]} @tab Punctuation characters (characters that are not letters, digits,
-control characters, or space characters).
-@item @code{[:space:]} @tab Space characters (such as space, TAB, and formfeed, to name a few).
-@item @code{[:upper:]} @tab Uppercase alphabetic characters.
-@item @code{[:xdigit:]} @tab Characters that are hexadecimal digits.
+control characters, or space characters)
+@item @code{[:space:]} @tab Space characters (such as space, TAB, and formfeed, to name a few)
+@item @code{[:upper:]} @tab Uppercase alphabetic characters
+@item @code{[:xdigit:]} @tab Characters that are hexadecimal digits
 @end multitable
 @end float
 
@@ -5391,12 +5556,12 @@ and numeric characters in your character set.
 @c Thanks to
 @c Date: Tue, 01 Jul 2014 07:39:51 +0200
 @c From: Hermann Peifer <peifer@gmx.eu>
-Some utilities that match regular expressions provide a non-standard
-@code{[:ascii:]} character class; @command{awk} does not. However, you
-can simulate such a construct using @code{[\x00-\x7F]}.  This matches
+Some utilities that match regular expressions provide a nonstandard
+@samp{[:ascii:]} character class; @command{awk} does not. However, you
+can simulate such a construct using @samp{[\x00-\x7F]}.  This matches
 all values numerically between zero and 127, which is the defined
 range of the ASCII character set.  Use a complemented character list
-(@code{[^\x00-\x7F]}) to match any single-byte characters that are not
+(@samp{[^\x00-\x7F]}) to match any single-byte characters that are not
 in the ASCII range.
 
 @cindex bracket expressions, collating elements
@@ -5425,8 +5590,8 @@ Locale-specific names for a list of
 characters that are equal. The name is enclosed between
 @samp{[=} and @samp{=]}.
 For example, the name @samp{e} might be used to represent all of
-``e,'' ``@`e,'' and ``@'e.'' In this case, @samp{[[=e=]]} is a regexp
-that matches any of @samp{e}, @samp{@'e}, or @samp{@`e}.
+``e,'' ``@^e,'' ``@`e,'' and ``@'e.'' In this case, @samp{[[=e=]]} is a regexp
+that matches any of @samp{e}, @samp{@^e}, @samp{@'e}, or @samp{@`e}.
 @end table
 
 These features are very valuable in non-English-speaking locales.
@@ -5440,7 +5605,6 @@ expression matching currently recognize only POSIX character classes;
 they do not recognize collating symbols or equivalence classes.
 @end quotation
 @c maybe one day ...
-@c ENDOFRANGE charlist
 
 @node Leftmost Longest
 @section How Much Text Matches?
@@ -5456,7 +5620,7 @@ echo aaaabcd | awk '@{ sub(/a+/, "<A>"); print @}'
 This example uses the @code{sub()} function to make a change to the input
 record.  (@code{sub()} replaces the first instance of any text matched
 by the first argument with the string provided as the second argument;
-@pxref{String Functions}).  Here, the regexp @code{/a+/} indicates ``one
+@pxref{String Functions}.)  Here, the regexp @code{/a+/} indicates ``one
 or more @samp{a} characters,'' and the replacement text is @samp{<A>}.
 
 The input contains four @samp{a} characters.
@@ -5484,9 +5648,7 @@ and also @pxref{Field Separators}).
 @node Computed Regexps
 @section Using Dynamic Regexps
 
-@c STARTOFRANGE dregexp
 @cindex regular expressions, computed
-@c STARTOFRANGE regexpd
 @cindex regular expressions, dynamic
 @cindex @code{~} (tilde), @code{~} operator
 @cindex tilde (@code{~}), @code{~} operator
@@ -5512,14 +5674,14 @@ and tests whether the input record matches this regexp.
 
 @quotation NOTE
 When using the @samp{~} and @samp{!~}
-operators, there is a difference between a regexp constant
+operators, be aware that there is a difference between a regexp constant
 enclosed in slashes and a string constant enclosed in double quotes.
 If you are going to use a string constant, you have to understand that
 the string is, in essence, scanned @emph{twice}: the first time when
 @command{awk} reads your program, and the second time when it goes to
 match the string on the lefthand side of the operator with the pattern
 on the right.  This is true of any string-valued expression (such as
-@code{digits_regexp}, shown previously), not just string constants.
+@code{digits_regexp}, shown in the previous example), not just string constants.
 @end quotation
 
 @cindex regexp constants, slashes vs.@: quotes
@@ -5577,7 +5739,7 @@ $ @kbd{awk '$0 ~ "[ \t\n]"'}
 @error{} ]...
 @error{}  source line number 1
 @error{}  context is
-@error{}        $0 ~ "[ >>>  \t\n]" <<< 
+@error{}        $0 ~ "[ >>>  \t\n]" <<<
 @end example
 
 @cindex newlines, in regexp constants
@@ -5593,17 +5755,13 @@ $ @kbd{awk '$0 ~ /[ \t\n]/'}
 @command{gawk} does not have this problem, and it isn't likely to
 occur often in practice, but it's worth noting for future reference.
 @end sidebar
-@c ENDOFRANGE dregexp
-@c ENDOFRANGE regexpd
 
 @node GNU Regexp Operators
 @section @command{gawk}-Specific Regexp Operators
 
 @c This section adapted (long ago) from the regex-0.12 manual
 
-@c STARTOFRANGE regexpg
 @cindex regular expressions, operators, @command{gawk}
-@c STARTOFRANGE gregexp
 @cindex @command{gawk}, regular expressions, operators
 @cindex operators, GNU-specific
 @cindex regular expressions, operators, for words
@@ -5679,7 +5837,7 @@ matches either @samp{ball} or @samp{balls}, as a separate word.
 @item \B
 Matches the empty string that occurs between two
 word-constituent characters. For example,
-@code{/\Brat\B/} matches @samp{crate} but it does not match @samp{dirty rat}.
+@code{/\Brat\B/} matches @samp{crate}, but it does not match @samp{dirty rat}.
 @samp{\B} is essentially the opposite of @samp{\y}.
 @end table
 
@@ -5687,9 +5845,9 @@ word-constituent characters. For example,
 @cindex regular expressions, operators, for buffers
 @cindex operators, string-matching, for buffers
 There are two other operators that work on buffers.  In Emacs, a
-@dfn{buffer} is, naturally, an Emacs buffer.  For other programs,
-@command{gawk}'s regexp library routines consider the entire
-string to match as the buffer.
+@dfn{buffer} is, naturally, an Emacs buffer.
+Other GNU programs, including @command{gawk},
+consider the entire string to match as the buffer.
 The operators are:
 
 @table @code
@@ -5698,14 +5856,14 @@ The operators are:
 @cindex backslash (@code{\}), @code{\`} operator (@command{gawk})
 @cindex @code{\} (backslash), @code{\`} operator (@command{gawk})
 Matches the empty string at the
-beginning of a buffer (string).
+beginning of a buffer (string)
 
 @c @cindex operators, @code{\'} (@command{gawk})
 @cindex backslash (@code{\}), @code{\'} operator (@command{gawk})
 @cindex @code{\} (backslash), @code{\'} operator (@command{gawk})
 @item \'
 Matches the empty string at the
-end of a buffer (string).
+end of a buffer (string)
 @end table
 
 @cindex @code{^} (caret), regexp operator
@@ -5750,16 +5908,16 @@ in @ref{Regexp Operators}.
 @end ifnottex
 
 @item @code{--posix}
-Only POSIX regexps are supported; the GNU operators are not special
+Match only POSIX regexps; the GNU operators are not special
 (e.g., @samp{\w} matches a literal @samp{w}).  Interval expressions
 are allowed.
 
 @cindex Brian Kernighan's @command{awk}
 @item @code{--traditional}
-Traditional Unix @command{awk} regexps are matched. The GNU operators
+Match traditional Unix @command{awk} regexps. The GNU operators
 are not special, and interval expressions are not available.
-The POSIX character classes (@samp{[[:alnum:]]}, etc.) are supported,
-as BWK @command{awk} supports them.
+Because BWK @command{awk} supports them,
+the POSIX character classes (@samp{[[:alnum:]]}, etc.) are available.
 Characters described by octal and hexadecimal escape sequences are
 treated literally, even if they represent regexp metacharacters.
 
@@ -5768,15 +5926,11 @@ Allow interval expressions in regexps, if @option{--traditional}
 has been provided.
 Otherwise, interval expressions are available by default.
 @end table
-@c ENDOFRANGE gregexp
-@c ENDOFRANGE regexpg
 
 @node Case-sensitivity
 @section Case Sensitivity in Matching
 
-@c STARTOFRANGE regexpcs
 @cindex regular expressions, case sensitivity
-@c STARTOFRANGE csregexp
 @cindex case sensitivity, regexps and
 Case is normally significant in regular expressions, both when matching
 ordinary characters (i.e., not metacharacters) and inside bracket
@@ -5819,7 +5973,7 @@ When @code{IGNORECASE} is not zero, @emph{all} regexp and string
 operations ignore case.
 
 Changing the value of @code{IGNORECASE} dynamically controls the
-case-sensitivity of the program as it runs.  Case is significant by
+case sensitivity of the program as it runs.  Case is significant by
 default because @code{IGNORECASE} (like most variables) is initialized
 to zero:
 
@@ -5832,7 +5986,7 @@ if (x ~ /ab/) @dots{}   # now it will succeed
 @end example
 
 In general, you cannot use @code{IGNORECASE} to make certain rules
-case-insensitive and other rules case-sensitive, because there is no
+case insensitive and other rules case sensitive, as there is no
 straightforward way
 to set @code{IGNORECASE} just for the pattern of
 a particular rule.@footnote{Experienced C and C++ programmers will note
@@ -5843,13 +5997,13 @@ and
 However, this is somewhat obscure and we don't recommend it.}
 To do this, use either bracket expressions or @code{tolower()}.  However, one
 thing you can do with @code{IGNORECASE} only is dynamically turn
-case-sensitivity on or off for all the rules at once.
+case sensitivity on or off for all the rules at once.
 
 @code{IGNORECASE} can be set on the command line or in a @code{BEGIN} rule
 (@pxref{Other Arguments}; also
 @pxref{Using BEGIN/END}).
 Setting @code{IGNORECASE} from the command line is a way to make
-a program case-insensitive without having to edit it.
+a program case insensitive without having to edit it.
 
 @c @cindex ISO 8859-1
 @c @cindex ISO Latin-1
@@ -5868,8 +6022,6 @@ the right thing.}
 The value of @code{IGNORECASE} has no effect if @command{gawk} is in
 compatibility mode (@pxref{Options}).
 Case is always significant in compatibility mode.
-@c ENDOFRANGE csregexp
-@c ENDOFRANGE regexpcs
 
 @node Regexp Summary
 @section Summary
@@ -5886,12 +6038,12 @@ in conditional expressions, or as part of matching expressions
 using the @samp{~} and @samp{!~} operators.
 
 @item
-Escape sequences let you represent non-printable characters and
+Escape sequences let you represent nonprintable characters and
 also let you represent regexp metacharacters as literal characters
 to be matched.
 
 @item
-Regexp operators provide grouping, alternation and repetition.
+Regexp operators provide grouping, alternation, and repetition.
 
 @item
 Bracket expressions give you a shorthand for specifying sets
@@ -5906,8 +6058,8 @@ the match, such as for text substitution and when the record separator
 is a regexp.
 
 @item
-Matching expressions may use dynamic regexps, that is, string values
-treated as regular expressions.
+Matching expressions may use dynamic regexps (i.e., string values
+treated as regular expressions).
 
 @item
 @command{gawk}'s @code{IGNORECASE} variable lets you control the
@@ -5916,12 +6068,10 @@ versions, use @code{tolower()} or @code{toupper()}.
 
 @end itemize
 
-@c ENDOFRANGE regexp
 
 @node Reading Files
 @chapter Reading Input Files
 
-@c STARTOFRANGE infir
 @cindex reading input files
 @cindex input files, reading
 @cindex input files
@@ -5946,7 +6096,7 @@ This makes it more convenient for programs to work on the parts of a record.
 
 @cindex @code{getline} command
 On rare occasions, you may need to use the @code{getline} command.
-The  @code{getline} command is valuable, both because it
+The  @code{getline} command is valuable both because it
 can do explicit input from any number of files, and because the files
 used with it do not have to be named on the @command{awk} command line
 (@pxref{Getline}).
@@ -5963,6 +6113,7 @@ used with it do not have to be named on the @command{awk} command line
 * Getline::                     Reading files under explicit program control
                                 using the @code{getline} function.
 * Read Timeout::                Reading input with a timeout.
+* Retrying Input::              Retrying input after certain errors.
 * Command-line directories::    What happens if you put a directory on the
                                 command line.
 * Input Summary::               Input summary.
@@ -5972,16 +6123,14 @@ used with it do not have to be named on the @command{awk} command line
 @node Records
 @section How Input Is Split into Records
 
-@c STARTOFRANGE inspl
 @cindex input, splitting into records
-@c STARTOFRANGE recspl
 @cindex records, splitting input into
 @cindex @code{NR} variable
 @cindex @code{FNR} variable
 @command{awk} divides the input for your program into records and fields.
 It keeps track of the number of records that have been read so far from
 the current input file.  This value is stored in a predefined variable
-called @code{FNR} which is reset to zero every time a new file is started.
+called @code{FNR}, which is reset to zero every time a new file is started.
 Another predefined variable, @code{NR}, records the total number of input
 records read so far from all @value{DF}s.  It starts at zero, but is
 never automatically reset to zero.
@@ -5992,15 +6141,15 @@ never automatically reset to zero.
 @end menu
 
 @node awk split records
-@subsection Record Splitting With Standard @command{awk}
+@subsection Record Splitting with Standard @command{awk}
 
 @cindex separators, for records
 @cindex record separators
 Records are separated by a character called the @dfn{record separator}.
 By default, the record separator is the newline character.
 This is why records are, by default, single lines.
-A different character can be used for the record separator by
-assigning the character to the predefined variable @code{RS}.
+To use a different character for the record separator,
+simply assign that character to the predefined variable @code{RS}.
 
 @cindex newlines, as record separators
 @cindex @code{RS} variable
@@ -6009,7 +6158,7 @@ the value of @code{RS} can be changed in the @command{awk} program
 with the assignment operator, @samp{=}
 (@pxref{Assignment Ops}).
 The new record-separator character should be enclosed in quotation marks,
-which indicate a string constant.  Often the right time to do this is
+which indicate a string constant.  Often, the right time to do this is
 at the beginning of execution, before any input is processed,
 so that the very first record is read with the proper separator.
 To do this, use the special @code{BEGIN} pattern
@@ -6023,8 +6172,8 @@ awk 'BEGIN @{ RS = "u" @}
 
 @noindent
 changes the value of @code{RS} to @samp{u}, before reading any input.
-This is a string whose first character is the letter ``u;'' as a result, records
-are separated by the letter ``u.''  Then the input file is read, and the second
+The new value is a string whose first character is the letter ``u''; as a result, records
+are separated by the letter ``u''.  Then the input file is read, and the second
 rule in the @command{awk} program (the action with no pattern) prints each
 record.  Because each @code{print} statement adds a newline at the end of
 its output, this @command{awk} program copies the input
@@ -6071,7 +6220,7 @@ $ @kbd{awk 'BEGIN @{ RS = "u" @}}
 @print{} m@@ny
 @print{} .ed
 @print{}      R
-@print{} 
+@print{}
 @end example
 
 @noindent
@@ -6085,8 +6234,8 @@ Bill         555-1675     bill.drowning@@hotmail.com       A
 @end example
 
 @noindent
-It contains no @samp{u} so there is no reason to split the record,
-unlike the others which have one or more occurrences of the @samp{u}.
+It contains no @samp{u}, so there is no reason to split the record,
+unlike the others, which each have one or more occurrences of the @samp{u}.
 In fact, this record is treated as part of the previous record;
 the newline separating them in the output
 is the original newline in the @value{DF}, not the one added by
@@ -6117,7 +6266,7 @@ being fully POSIX-compliant (@pxref{Options}).
 Then, the following (extreme) pipeline prints a surprising @samp{1}:
 
 @example
-$ echo | gawk --posix 'BEGIN @{ RS = "a" @} ; @{ print NF @}'
+$ @kbd{echo | gawk --posix 'BEGIN @{ RS = "a" @} ; @{ print NF @}'}
 @print{} 1
 @end example
 
@@ -6139,7 +6288,7 @@ The empty string @code{""} (a string without any characters)
 has a special meaning
 as the value of @code{RS}. It means that records are separated
 by one or more blank lines and nothing else.
-@xref{Multiple Line}, for more details.
+@DBXREF{Multiple Line} for more details.
 
 If you change the value of @code{RS} in the middle of an @command{awk} run,
 the new value is used to delimit subsequent records, but the record
@@ -6159,7 +6308,7 @@ sets the variable @code{RT} to the text in the input that matched
 @code{RS}.
 
 @node gawk split records
-@subsection Record Splitting With @command{gawk}
+@subsection Record Splitting with @command{gawk}
 
 @cindex common extensions, @code{RS} as a regexp
 @cindex extensions, common@comma{} @code{RS} as a regexp
@@ -6181,7 +6330,7 @@ contains the same single character. However, when @code{RS} is a
 regular expression, @code{RT} contains
 the actual input text that matched the regular expression.
 
-If the input file ended without any text that matches @code{RS},
+If the input file ends without any text matching @code{RS},
 @command{gawk} sets @code{RT} to the null string.
 
 The following example illustrates both of these features.
@@ -6203,11 +6352,11 @@ $ @kbd{echo record 1 AAAA record 2 BBBB record 3 |}
 The square brackets delineate the contents of @code{RT}, letting you
 see the leading and trailing whitespace. The final value of
 @code{RT} is a newline.
-@xref{Simple Sed}, for a more useful example
+@DBXREF{Simple Sed} for a more useful example
 of @code{RS} as a regexp and @code{RT}.
 
 If you set @code{RS} to a regular expression that allows optional
-trailing text, such as @samp{RS = "abc(XYZ)?"} it is possible, due
+trailing text, such as @samp{RS = "abc(XYZ)?"}, it is possible, due
 to implementation constraints, that @command{gawk} may match the leading
 part of the regular expression, but not the trailing part, particularly
 if the input text that could match the trailing part is fairly long.
@@ -6221,7 +6370,7 @@ the beginning and end of a @emph{line}.  As a result, something like
 @samp{RS = "^[[:upper:]]"} can only match at the beginning of a file.
 This is because @command{gawk} views the input file as one long string
 that happens to contain newline characters.
-It is thus best to avoid anchor characters in the value of @code{RS}.
+It is thus best to avoid anchor metacharacters in the value of @code{RS}.
 @end quotation
 
 @cindex differences in @command{awk} and @command{gawk}, @code{RS}/@code{RT} variables
@@ -6240,7 +6389,7 @@ a value that you know doesn't occur in the input file.  This is hard
 to do in a general way, such that a program always works for arbitrary
 input files.
 
-You might think that for text files, the @value{NUL} character, which
+You might think that for text files, the @sc{nul} character, which
 consists of a character with all bits equal to zero, is a good
 value to use for @code{RS} in this case:
 
@@ -6249,33 +6398,31 @@ BEGIN @{ RS = "\0" @}  # whole file becomes one record?
 @end example
 
 @cindex differences in @command{awk} and @command{gawk}, strings, storing
-@command{gawk} in fact accepts this, and uses the @value{NUL}
+@command{gawk} in fact accepts this, and uses the @sc{nul}
 character for the record separator.
 This works for certain special files, such as @file{/proc/environ} on
-GNU/Linux systems, where the @value{NUL} character is in fact the record separator.
+GNU/Linux systems, where the @sc{nul} character is in fact the record separator.
 However, this usage is @emph{not} portable
 to most other @command{awk} implementations.
 
 @cindex dark corner, strings, storing
 Almost all other @command{awk} implementations@footnote{At least that we know
 about.} store strings internally as C-style strings.  C strings use the
-@value{NUL} character as the string terminator.  In effect, this means that
+@sc{nul} character as the string terminator.  In effect, this means that
 @samp{RS = "\0"} is the same as @samp{RS = ""}.
 @value{DARKCORNER}
 
-It happens that recent versions of @command{mawk} can use the @value{NUL}
+It happens that recent versions of @command{mawk} can use the @sc{nul}
 character as a record separator. However, this is a special case:
-@command{mawk} does not allow embedded @value{NUL} characters in strings.
+@command{mawk} does not allow embedded @sc{nul} characters in strings.
 (This may change in a future version of @command{mawk}.)
 
 @cindex records, treating files as
 @cindex treating files, as single records
-@xref{Readfile Function}, for an interesting way to read
-whole files.  If you are using @command{gawk}, see @ref{Extension Sample
-Readfile}, for another option.
+@DBXREF{Readfile Function} for an interesting way to read
+whole files.  If you are using @command{gawk}, see @DBREF{Extension Sample
+Readfile} for another option.
 @end sidebar
-@c ENDOFRANGE inspl
-@c ENDOFRANGE recspl
 
 @node Fields
 @section Examining Fields
@@ -6283,7 +6430,6 @@ Readfile}, for another option.
 @cindex examining fields
 @cindex fields
 @cindex accessing fields
-@c STARTOFRANGE fiex
 @cindex fields, examining
 @cindex POSIX @command{awk}, field separators and
 @cindex field separators, POSIX and
@@ -6294,9 +6440,9 @@ called @dfn{fields}.  By default, fields are separated by @dfn{whitespace},
 like words in a line.
 Whitespace in @command{awk} means any string of one or more spaces,
 TABs, or newlines;@footnote{In POSIX @command{awk}, newlines are not
-considered whitespace for separating fields.} other characters, such as
-formfeed, vertical tab, etc., that are
-considered whitespace by other languages, are @emph{not} considered
+considered whitespace for separating fields.} other characters
+that are considered whitespace by other languages
+(such as formfeed, vertical tab, etc.) are @emph{not} considered
 whitespace by @command{awk}.
 
 The purpose of fields is to make it more convenient for you to refer to
@@ -6308,12 +6454,12 @@ simple @command{awk} programs so powerful.
 @cindex @code{$} (dollar sign), @code{$} field operator
 @cindex dollar sign (@code{$}), @code{$} field operator
 @cindex field operators@comma{} dollar sign as
-You use a dollar-sign (@samp{$})
+You use a dollar sign (@samp{$})
 to refer to a field in an @command{awk} program,
 followed by the number of the field you want.  Thus, @code{$1}
 refers to the first field, @code{$2} to the second, and so on.
-(Unlike the Unix shells, the field numbers are not limited to single digits.
-@code{$127} is the one hundred twenty-seventh field in the record.)
+(Unlike in the Unix shells, the field numbers are not limited to single digits.
+@code{$127} is the 127th field in the record.)
 For example, suppose the following is a line of input:
 
 @example
@@ -6338,7 +6484,7 @@ If you try to reference a field beyond the last
 one (such as @code{$8} when the record has only seven fields), you get
 the empty string.  (If used in a numeric operation, you get zero.)
 
-The use of @code{$0}, which looks like a reference to the ``zero-th'' field, is
+The use of @code{$0}, which looks like a reference to the ``zeroth'' field, is
 a special case: it represents the whole input record. Use it
 when you are not interested in specific fields.
 Here are some more examples:
@@ -6364,7 +6510,6 @@ $ @kbd{awk '/li/ @{ print $1, $NF @}' mail-list}
 @print{} Julie F
 @print{} Samuel A
 @end example
-@c ENDOFRANGE fiex
 
 @node Nonconstant Fields
 @section Nonconstant Field Numbers
@@ -6383,7 +6528,7 @@ awk '@{ print $NR @}'
 
 @noindent
 Recall that @code{NR} is the number of records read so far: one in the
-first record, two in the second, etc.  So this example prints the first
+first record, two in the second, and so on.  So this example prints the first
 field of the first record, the second field of the second record, and so
 on.  For the twentieth record, field number 20 is printed; most likely,
 the record has fewer than 20 fields, so this prints a blank line.
@@ -6394,13 +6539,13 @@ awk '@{ print $(2*2) @}' mail-list
 @end example
 
 @command{awk} evaluates the expression @samp{(2*2)} and uses
-its value as the number of the field to print.  The @samp{*} sign
+its value as the number of the field to print.  The @samp{*}
 represents multiplication, so the expression @samp{2*2} evaluates to four.
 The parentheses are used so that the multiplication is done before the
 @samp{$} operation; they are necessary whenever there is a binary
 operator@footnote{A @dfn{binary operator}, such as @samp{*} for
 multiplication, is one that takes two operands. The distinction
-is required, since @command{awk} also has unary (one-operand)
+is required because @command{awk} also has unary (one-operand)
 and ternary (three-operand) operators.}
 in the field-number expression.  This example, then, prints the
 type of relationship (the fourth field) for every line of the file
@@ -6425,7 +6570,6 @@ evaluating @code{NF} and using its value as a field number.
 @node Changing Fields
 @section Changing the Contents of a Field
 
-@c STARTOFRANGE ficon
 @cindex fields, changing contents of
 The contents of a field, as seen by @command{awk}, can be changed within an
 @command{awk} program; this changes what @command{awk} perceives as the
@@ -6474,7 +6618,7 @@ $ @kbd{awk '@{ $2 = $2 - 10; print $0 @}' inventory-shipped}
 @dots{}
 @end example
 
-It is also possible to also assign contents to fields that are out
+It is also possible to assign contents to fields that are out
 of range.  For example:
 
 @example
@@ -6525,9 +6669,9 @@ else
 
 @noindent
 should print @samp{everything is normal}, because @code{NF+1} is certain
-to be out of range.  (@xref{If Statement},
+to be out of range.  (@DBXREF{If Statement}
 for more information about @command{awk}'s @code{if-else} statements.
-@xref{Typing and Comparison},
+@DBXREF{Typing and Comparison}
 for more information about the @samp{!=} operator.)
 
 It is important to note that making an assignment to an existing field
@@ -6567,8 +6711,8 @@ after the new value of @code{NF} and recomputes @code{$0}.
 Here is an example:
 
 @example
-$ echo a b c d e f | awk '@{ print "NF =", NF;
->                           NF = 3; print $0 @}'
+$ @kbd{echo a b c d e f | awk '@{ print "NF =", NF;}
+> @kbd{                          NF = 3; print $0 @}'}
 @print{} NF = 6
 @print{} a b c
 @end example
@@ -6581,7 +6725,7 @@ rebuild @code{$0} when @code{NF} is decremented.
 
 Finally, there are times when it is convenient to force
 @command{awk} to rebuild the entire record, using the current
-value of the fields and @code{OFS}.  To do this, use the
+values of the fields and @code{OFS}.  To do this, use the
 seemingly innocuous assignment:
 
 @example
@@ -6605,19 +6749,18 @@ such as @code{sub()} and @code{gsub()}
 It is important to remember that @code{$0} is the @emph{full}
 record, exactly as it was read from the input.  This includes
 any leading or trailing whitespace, and the exact whitespace (or other
-characters) that separate the fields.
+characters) that separates the fields.
 
 It is a common error to try to change the field separators
 in a record simply by setting @code{FS} and @code{OFS}, and then
 expecting a plain @samp{print} or @samp{print $0} to print the
 modified record.
 
-But this does not work, since nothing was done to change the record
+But this does not work, because nothing was done to change the record
 itself.  Instead, you must force the record to be rebuilt, typically
 with a statement such as @samp{$1 = $1}, as described earlier.
 @end sidebar
 
-@c ENDOFRANGE ficon
 
 @node Field Separators
 @section Specifying How Fields Are Separated
@@ -6633,9 +6776,7 @@ with a statement such as @samp{$1 = $1}, as described earlier.
 
 @cindex @code{FS} variable
 @cindex fields, separating
-@c STARTOFRANGE fisepr
 @cindex field separators
-@c STARTOFRANGE fisepg
 @cindex fields, separating
 The @dfn{field separator}, which is either a single character or a regular
 expression, controls the way @command{awk} splits an input record into fields.
@@ -6664,7 +6805,7 @@ the Unix Bourne shell, @command{sh}, or Bash).
 @cindex @code{FS} variable, changing value of
 The value of @code{FS} can be changed in the @command{awk} program with the
 assignment operator, @samp{=} (@pxref{Assignment Ops}).
-Often the right time to do this is at the beginning of execution
+Often, the right time to do this is at the beginning of execution
 before any input has been processed, so that the very first record
 is read with the proper separator.  To do this, use the special
 @code{BEGIN} pattern
@@ -6701,7 +6842,7 @@ John Q. Smith, LXIX, 29 Oak St., Walamazoo, MI 42139
 @end example
 
 @noindent
-The same program would extract @samp{@bullet{}LXIX}, instead of
+The same program would extract @samp{@bullet{}LXIX} instead of
 @samp{@bullet{}29@bullet{}Oak@bullet{}St.}.
 If you were expecting the program to print the
 address, you would be surprised.  The moral is to choose your data layout and
@@ -6735,9 +6876,7 @@ rules.
 @node Regexp Field Splitting
 @subsection Using Regular Expressions to Separate Fields
 
-@c STARTOFRANGE regexpfs
 @cindex regular expressions, as field separators
-@c STARTOFRANGE fsregexp
 @cindex field separators, regular expressions as
 The previous @value{SUBSECTION}
 discussed the use of single characters or simple strings as the
@@ -6820,7 +6959,7 @@ statement prints the new @code{$0}.
 @cindex dark corner, @code{^}, in @code{FS}
 There is an additional subtlety to be aware of when using regular expressions
 for field splitting.
-It is not well-specified in the POSIX standard, or anywhere else, what @samp{^}
+It is not well specified in the POSIX standard, or anywhere else, what @samp{^}
 means when splitting fields.  Does the @samp{^}  match only at the beginning of
 the entire record? Or is each field separator a new string?  It turns out that
 different @command{awk} versions answer this question differently, and you
@@ -6841,8 +6980,6 @@ $ @kbd{echo 'xxAA  xxBxx  C' |}
 @print{} -->xxBxx<--
 @print{} -->C<--
 @end example
-@c ENDOFRANGE regexpfs
-@c ENDOFRANGE fsregexp
 
 @node Single Character Fields
 @subsection Making Each Character a Separate Field
@@ -6966,7 +7103,7 @@ choosing your field and record separators.
 @cindex Unix @command{awk}, password files@comma{} field separators and
 Perhaps the most common use of a single character as the field separator
 occurs when processing the Unix system password file.  On many Unix
-systems, each user has a separate entry in the system password file, one
+systems, each user has a separate entry in the system password file, with one
 line per user.  The information in these lines is separated by colons.
 The first field is the user's login name and the second is the user's
 encrypted or shadow password.  (A shadow password is indicated by the
@@ -6986,11 +7123,11 @@ awk -F: '$5 == ""' /etc/passwd
 @end example
 
 @node Full Line Fields
-@subsection Making The Full Line Be A Single Field
+@subsection Making the Full Line Be a Single Field
 
 Occasionally, it's useful to treat the whole input line as a
 single field.  This can be done easily and portably simply by
-setting @code{FS} to @code{"\n"} (a newline).@footnote{Thanks to
+setting @code{FS} to @code{"\n"} (a newline):@footnote{Thanks to
 Andrew Schorr for this tip.}
 
 @example
@@ -7000,42 +7137,6 @@ awk -F'\n' '@var{program}' @var{files @dots{}}
 @noindent
 When you do this, @code{$1} is the same as @code{$0}.
 
-@node Field Splitting Summary
-@subsection Field-Splitting Summary
-
-It is important to remember that when you assign a string constant
-as the value of @code{FS}, it undergoes normal @command{awk} string
-processing.  For example, with Unix @command{awk} and @command{gawk},
-the assignment @samp{FS = "\.."} assigns the character string @code{".."}
-to @code{FS} (the backslash is stripped).  This creates a regexp meaning
-``fields are separated by occurrences of any two characters.''
-If instead you want fields to be separated by a literal period followed
-by any single character, use @samp{FS = "\\.."}.
-
-The following list summarizes how fields are split, based on the value
-of @code{FS} (@samp{==} means ``is equal to''):
-
-@table @code
-@item FS == " "
-Fields are separated by runs of whitespace.  Leading and trailing
-whitespace are ignored.  This is the default.
-
-@item FS == @var{any other single character}
-Fields are separated by each occurrence of the character.  Multiple
-successive occurrences delimit empty fields, as do leading and
-trailing occurrences.
-The character can even be a regexp metacharacter; it does not need
-to be escaped.
-
-@item FS == @var{regexp}
-Fields are separated by occurrences of characters that match @var{regexp}.
-Leading and trailing matches of @var{regexp} delimit empty fields.
-
-@item FS == ""
-Each individual character in the record becomes a separate field.
-(This is a common extension; it is not specified by the POSIX standard.)
-@end table
-
 @sidebar Changing @code{FS} Does Not Affect the Fields
 
 @cindex POSIX @command{awk}, field separators and
@@ -7043,7 +7144,7 @@ Each individual character in the record becomes a separate field.
 According to the POSIX standard, @command{awk} is supposed to behave
 as if each record is split into fields at the time it is read.
 In particular, this means that if you change the value of @code{FS}
-after a record is read, the value of the fields (i.e., how they were split)
+after a record is read, the values of the fields (i.e., how they were split)
 should reflect the old value of @code{FS}, not the new one.
 
 @cindex dark corner, field separators
@@ -7056,10 +7157,7 @@ using the @emph{current} value of @code{FS}!
 @value{DARKCORNER}
 This behavior can be difficult
 to diagnose. The following example illustrates the difference
-between the two methods.
-(The @command{sed}@footnote{The @command{sed} utility is a ``stream editor.''
-Its behavior is also defined by the POSIX standard.}
-command prints just the first line of @file{/etc/passwd}.)
+between the two methods:
 
 @example
 sed 1q /etc/passwd | awk '@{ FS = ":" ; print $1 @}'
@@ -7077,10 +7175,50 @@ on an incorrect implementation of @command{awk}, while @command{gawk}
 prints the full first line of the file, something like:
 
 @example
-root:nSijPlPhZZwgE:0:0:Root:/:
+root:x:0:0:Root:/:
 @end example
+
+(The @command{sed}@footnote{The @command{sed} utility is a ``stream editor.''
+Its behavior is also defined by the POSIX standard.}
+command prints just the first line of @file{/etc/passwd}.)
 @end sidebar
 
+@node Field Splitting Summary
+@subsection Field-Splitting Summary
+
+It is important to remember that when you assign a string constant
+as the value of @code{FS}, it undergoes normal @command{awk} string
+processing.  For example, with Unix @command{awk} and @command{gawk},
+the assignment @samp{FS = "\.."} assigns the character string @code{".."}
+to @code{FS} (the backslash is stripped).  This creates a regexp meaning
+``fields are separated by occurrences of any two characters.''
+If instead you want fields to be separated by a literal period followed
+by any single character, use @samp{FS = "\\.."}.
+
+The following list summarizes how fields are split, based on the value
+of @code{FS} (@samp{==} means ``is equal to''):
+
+@table @code
+@item FS == " "
+Fields are separated by runs of whitespace.  Leading and trailing
+whitespace are ignored.  This is the default.
+
+@item FS == @var{any other single character}
+Fields are separated by each occurrence of the character.  Multiple
+successive occurrences delimit empty fields, as do leading and
+trailing occurrences.
+The character can even be a regexp metacharacter; it does not need
+to be escaped.
+
+@item FS == @var{regexp}
+Fields are separated by occurrences of characters that match @var{regexp}.
+Leading and trailing matches of @var{regexp} delimit empty fields.
+
+@item FS == ""
+Each individual character in the record becomes a separate field.
+(This is a common extension; it is not specified by the POSIX standard.)
+@end table
+
 @sidebar @code{FS} and @code{IGNORECASE}
 
 The @code{IGNORECASE} variable
@@ -7099,30 +7237,28 @@ print $1
 @noindent
 The output is @samp{aCa}.  If you really want to split fields on an
 alphabetic character while ignoring case, use a regexp that will
-do it for you.  E.g., @samp{FS = "[c]"}.  In this case, @code{IGNORECASE}
+do it for you (e.g., @samp{FS = "[c]"}).  In this case, @code{IGNORECASE}
 will take effect.
 @end sidebar
 
-@c ENDOFRANGE fisepr
-@c ENDOFRANGE fisepg
 
 @node Constant Size
 @section Reading Fixed-Width Data
 
-@quotation NOTE
+@cindex data, fixed-width
+@cindex fixed-width data
+@cindex advanced features, fixed-width data
+
+@c O'Reilly doesn't like it as a note the first thing in the section.
 This @value{SECTION} discusses an advanced
 feature of @command{gawk}.  If you are a novice @command{awk} user,
 you might want to skip it on the first reading.
-@end quotation
 
-@cindex data, fixed-width
-@cindex fixed-width data
-@cindex advanced features, fixed-width data
-@command{gawk} provides a facility for dealing with
-fixed-width fields with no distinctive field separator.  For example,
-data of this nature arises in the input for old Fortran programs where
-numbers are run together, or in the output of programs that did not
-anticipate the use of their output as input for other programs.
+@command{gawk} provides a facility for dealing with fixed-width fields
+with no distinctive field separator.  For example, data of this nature
+arises in the input for old Fortran programs where numbers are run
+together, or in the output of programs that did not anticipate the use
+of their output as input for other programs.
 
 An example of the latter is a table where all the columns are lined up by
 the use of a variable number of spaces and @emph{empty fields are just
@@ -7142,7 +7278,7 @@ variable @code{FIELDWIDTHS}.  Each number specifies the width of the field,
 @emph{including} columns between fields.  If you want to ignore the columns
 between fields, you can specify the width as a separate field that is
 subsequently ignored.
-It is a fatal error to supply a field width that is not a positive number.
+It is a fatal error to supply a field width that has a negative value.
 The following data is the output of the Unix @command{w} utility.  It is useful
 to illustrate the use of @code{FIELDWIDTHS}:
 
@@ -7161,15 +7297,10 @@ dave     ttyq4    26Jun9115days     46     46  wnewmail
 @end group
 @end example
 
-The following program takes the above input, converts the idle time to
+The following program takes this input, converts the idle time to
 number of seconds, and prints out the first two fields and the calculated
 idle time:
 
-@quotation NOTE
-This program uses a number of @command{awk} features that
-haven't been introduced yet.
-@end quotation
-
 @example
 BEGIN  @{ FIELDWIDTHS = "9 6 10 6 7 7 35" @}
 NR > 2 @{
@@ -7188,6 +7319,11 @@ NR > 2 @{
 @}
 @end example
 
+@quotation NOTE
+The preceding program uses a number of @command{awk} features that
+haven't been introduced yet.
+@end quotation
+
 Running the program on the data produces the following results:
 
 @example
@@ -7219,7 +7355,7 @@ In order to tell which kind of field splitting is in effect,
 use @code{PROCINFO["FS"]}
 (@pxref{Auto-set}).
 The value is @code{"FS"} if regular field splitting is being used,
-or it is @code{"FIELDWIDTHS"} if fixed-width field splitting is being used:
+or @code{"FIELDWIDTHS"} if fixed-width field splitting is being used:
 
 @example
 if (PROCINFO["FS"] == "FS")
@@ -7233,17 +7369,16 @@ else
 This information is useful when writing a function
 that needs to temporarily change @code{FS} or @code{FIELDWIDTHS},
 read some records, and then restore the original settings
-(@pxref{Passwd Functions},
+(@DBPXREF{Passwd Functions}
 for an example of such a function).
 
 @node Splitting By Content
-@section Defining Fields By Content
+@section Defining Fields by Content
 
-@quotation NOTE
+@c O'Reilly doesn't like it as a note the first thing in the section.
 This @value{SECTION} discusses an advanced
 feature of @command{gawk}.  If you are a novice @command{awk} user,
 you might want to skip it on the first reading.
-@end quotation
 
 @cindex advanced features, specifying field content
 Normally, when using @code{FS}, @command{gawk} defines the fields as the
@@ -7254,14 +7389,16 @@ However, there are times when you really want to define the fields by
 what they are, and not by what they are not.
 
 The most notorious such case
-is so-called @dfn{comma separated value} (CSV) data. Many spreadsheet programs,
+is so-called @dfn{comma-separated values} (CSV) data. Many spreadsheet programs,
 for example, can export their data into text files, where each record is
-terminated with a newline, and fields are separated by commas. If only
-commas separated the data, there wouldn't be an issue. The problem comes when
-one of the fields contains an @emph{embedded} comma. While there is no
-formal standard specification for CSV data@footnote{At least, we don't know of one.},
-in such cases, most programs embed the field in double quotes. So we might
-have data like this:
+terminated with a newline, and fields are separated by commas. If
+commas only separated the data, there wouldn't be an issue. The problem comes when
+one of the fields contains an @emph{embedded} comma.
+In such cases, most programs embed the field in double quotes.@footnote{The
+CSV format lacked a formal standard definition for many years.
+@uref{http://www.ietf.org/rfc/rfc4180.txt, RFC 4180}
+standardizes the most common practices.}
+So, we might have data like this:
 
 @example
 @c file eg/misc/addresses.csv
@@ -7275,7 +7412,7 @@ The @code{FPAT} variable offers a solution for cases like this.
 The value of @code{FPAT} should be a string that provides a regular expression.
 This regular expression describes the contents of each field.
 
-In the case of CSV data as presented above, each field is either ``anything that
+In the case of CSV data as presented here, each field is either ``anything that
 is not a comma,'' or ``a double quote, anything that is not a double quote, and a
 closing double quote.''  If written as a regular expression constant
 (@pxref{Regexp}),
@@ -7340,15 +7477,15 @@ will be @code{"FPAT"} if content-based field splitting is being used.
 @quotation NOTE
 Some programs export CSV data that contains embedded newlines between
 the double quotes.  @command{gawk} provides no way to deal with this.
-Since there is no formal specification for CSV data, there isn't much
+Even though a formal specification for CSV data exists, there isn't much
 more to be done;
 the @code{FPAT} mechanism provides an elegant solution for the majority
-of cases, and the @command{gawk} developers are satisfied with that. 
+of cases, and the @command{gawk} developers are satisfied with that.
 @end quotation
 
 As written, the regexp used for @code{FPAT} requires that each field
-have a least one character.  A straightforward modification
-(changing changed the first @samp{+} to @samp{*}) allows fields to be empty:
+contain at least one character.  A straightforward modification
+(changing the first @samp{+} to @samp{*}) allows fields to be empty:
 
 @example
 FPAT = "([^,]*)|(\"[^\"]+\")"
@@ -7358,20 +7495,17 @@ Finally, the @code{patsplit()} function makes the same functionality
 available for splitting regular strings (@pxref{String Functions}).
 
 To recap, @command{gawk} provides three independent methods
-to split input records into fields. @command{gawk} uses whichever
-mechanism was last chosen based on which of the three
-variables---@code{FS}, @code{FIELDWIDTHS}, and @code{FPAT}---was
+to split input records into fields.
+The mechanism used is based on which of the three
+variables---@code{FS}, @code{FIELDWIDTHS}, or @code{FPAT}---was
 last assigned to.
 
 @node Multiple Line
 @section Multiple-Line Records
 
 @cindex multiple-line records
-@c STARTOFRANGE recm
 @cindex records, multiline
-@c STARTOFRANGE imr
 @cindex input, multiline records
-@c STARTOFRANGE frm
 @cindex files, reading, multiline records
 @cindex input, files, See input files
 In some databases, a single line cannot conveniently hold all the
@@ -7406,7 +7540,7 @@ at the end of the record and one or more blank lines after the record.
 In addition, a regular expression always matches the longest possible
 sequence when there is a choice
 (@pxref{Leftmost Longest}).
-So the next record doesn't start until
+So, the next record doesn't start until
 the first nonblank line that follows---no matter how many blank lines
 appear in a row, they are considered one record separator.
 
@@ -7421,10 +7555,10 @@ In the second case, this special processing is not done.
 @cindex field separator, in multiline records
 @cindex @code{FS}, in multiline records
 Now that the input is separated into records, the second step is to
-separate the fields in the record.  One way to do this is to divide each
+separate the fields in the records.  One way to do this is to divide each
 of the lines into fields in the normal manner.  This happens by default
 as the result of a special feature.  When @code{RS} is set to the empty
-string, @emph{and} @code{FS} is set to a single character,
+string @emph{and} @code{FS} is set to a single character,
 the newline character @emph{always} acts as a field separator.
 This is in addition to whatever field separations result from
 @code{FS}.@footnote{When @code{FS} is the null string (@code{""})
@@ -7439,7 +7573,7 @@ want the newline character to separate fields, because there is no way to
 prevent it.  However, you can work around this by using the @code{split()}
 function to break up the record manually
 (@pxref{String Functions}).
-If you have a single character field separator, you can work around
+If you have a single-character field separator, you can work around
 the special feature in a different way, by making @code{FS} into a
 regexp for that single character.  For example, if the field
 separator is a percent character, instead of
@@ -7447,10 +7581,10 @@ separator is a percent character, instead of
 
 Another way to separate fields is to
 put each field on a separate line: to do this, just set the
-variable @code{FS} to the string @code{"\n"}.  (This single
-character separator matches a single newline.)
+variable @code{FS} to the string @code{"\n"}.
+(This single-character separator matches a single newline.)
 A practical example of a @value{DF} organized this way might be a mailing
-list, where each entry is separated by blank lines.  Consider a mailing
+list, where blank lines separate the entries.  Consider a mailing
 list in a file named @file{addresses}, which looks like this:
 
 @example
@@ -7497,7 +7631,7 @@ $ @kbd{awk -f addrs.awk addresses}
 @dots{}
 @end example
 
-@xref{Labels Program}, for a more realistic program that deals with
+@DBXREF{Labels Program} for a more realistic program dealing with
 address lists.  The following list summarizes how records are split,
 based on the value of
 @ifinfo
@@ -7538,20 +7672,15 @@ If not in compatibility mode (@pxref{Options}), @command{gawk} sets
 @code{RT} to the input text that matched the value specified by @code{RS}.
 But if the input file ended without any text that matches @code{RS},
 then @command{gawk} sets @code{RT} to the null string.
-@c ENDOFRANGE recm
-@c ENDOFRANGE imr
-@c ENDOFRANGE frm
 
 @node Getline
 @section Explicit Input with @code{getline}
 
-@c STARTOFRANGE getl
 @cindex @code{getline} command, explicit input with
-@c STARTOFRANGE inex
 @cindex input, explicit
 So far we have been getting our input data from @command{awk}'s main
 input stream---either the standard input (usually your keyboard, sometimes
-the output from another program) or from the
+the output from another program) or the
 files specified on the command line.  The @command{awk} language has a
 special built-in command called @code{getline} that
 can be used to read input under your explicit control.
@@ -7587,12 +7716,19 @@ a record, such as a file that cannot be opened, then @code{getline}
 returns @minus{}1.  In this case, @command{gawk} sets the variable
 @code{ERRNO} to a string describing the error that occurred.
 
+If @code{ERRNO} indicates that the I/O operation may be
+retried, and @code{PROCINFO["@var{input}", "RETRY"]} is set,
+then @code{getline} returns @minus{}2
+instead of @minus{}1, and further calls to @code{getline}
+may be attemped.  @DBXREF{Retrying Input} for further information about
+this feature.
+
 In the following examples, @var{command} stands for a string value that
 represents a shell command.
 
 @quotation NOTE
 When @option{--sandbox} is specified (@pxref{Options}),
-reading lines from files, pipes and coprocesses is disabled.
+reading lines from files, pipes, and coprocesses is disabled.
 @end quotation
 
 @menu
@@ -7735,7 +7871,7 @@ free
 @end example
 
 The @code{getline} command used in this way sets only the variables
-@code{NR}, @code{FNR} and @code{RT} (and of course, @var{var}).
+@code{NR}, @code{FNR}, and @code{RT} (and, of course, @var{var}).
 The record is not
 split into fields, so the values of the fields (including @code{$0}) and
 the value of @code{NF} do not change.
@@ -7750,7 +7886,7 @@ the value of @code{NF} do not change.
 @cindex left angle bracket (@code{<}), @code{<} operator (I/O)
 @cindex operators, input/output
 Use @samp{getline < @var{file}} to read the next record from @var{file}.
-Here @var{file} is a string-valued expression that
+Here, @var{file} is a string-valued expression that
 specifies the @value{FN}.  @samp{< @var{file}} is called a @dfn{redirection}
 because it directs input to come from a different place.
 For example, the following
@@ -7789,7 +7925,7 @@ you want your program to be portable to all @command{awk} implementations.
 
 Use @samp{getline @var{var} < @var{file}} to read input
 from the file
-@var{file}, and put it in the variable @var{var}.  As above, @var{file}
+@var{file}, and put it in the variable @var{var}.  As earlier, @var{file}
 is a string-valued expression that specifies the file from which to read.
 
 In this version of @code{getline}, none of the predefined variables are
@@ -7825,7 +7961,7 @@ One deficiency of this program is that it does not process nested
 @code{@@include} statements
 (i.e., @code{@@include} statements in included files)
 the way a true macro preprocessor would.
-@xref{Igawk Program}, for a program
+@DBXREF{Igawk Program} for a program
 that does handle nested @code{@@include} statements.
 
 @node Getline/Pipe
@@ -7928,7 +8064,7 @@ of a construct like @samp{@w{"echo "} "date" | getline}.
 Most versions, including the current version, treat it at as
 @samp{@w{("echo "} "date") | getline}.
 (This is also how BWK @command{awk} behaves.)
-Some versions changed and treated it as
+Some versions instead treat it as
 @samp{@w{"echo "} ("date" | getline)}.
 (This is how @command{mawk} behaves.)
 In short, @emph{always} use explicit parentheses, and then you won't
@@ -7976,7 +8112,7 @@ program to be portable to other @command{awk} implementations.
 @cindex operators, input/output
 @cindex differences in @command{awk} and @command{gawk}, input/output operators
 
-Input into @code{getline} from a pipe is a one-way operation.
+Reading input into @code{getline} from a pipe is a one-way operation.
 The command that is started with @samp{@var{command} | getline} only
 sends data @emph{to} your @command{awk} program.
 
@@ -7986,7 +8122,7 @@ for processing and then read the results back.
 communications are possible.  This is done with the @samp{|&}
 operator.
 Typically, you write data to the coprocess first and then
-read results back, as shown in the following:
+read the results back, as shown in the following:
 
 @example
 print "@var{some query}" |& "db_server"
@@ -8069,17 +8205,23 @@ also @pxref{Auto-set}.)
 @item
 Using @code{FILENAME} with @code{getline}
 (@samp{getline < FILENAME})
-is likely to be a source for
+is likely to be a source of
 confusion.  @command{awk} opens a separate input stream from the
 current input file.  However, by not using a variable, @code{$0}
-and @code{NR} are still updated.  If you're doing this, it's
+and @code{NF} are still updated.  If you're doing this, it's
 probably by accident, and you should reconsider what it is you're
 trying to accomplish.
 
 @item
-@DBREF{Getline Summary} presents a table summarizing the
+@ifdocbook
+The next section
+@end ifdocbook
+@ifnotdocbook
+@ref{Getline Summary},
+@end ifnotdocbook
+presents a table summarizing the
 @code{getline} variants and which variables they can affect.
-It is worth noting that those variants which do not use redirection
+It is worth noting that those variants that do not use redirection
 can cause @code{FILENAME} to be updated if they cause
 @command{awk} to start reading a new input file.
 
@@ -8088,7 +8230,7 @@ can cause @code{FILENAME} to be updated if they cause
 If the variable being assigned is an expression with side effects,
 different versions of @command{awk} behave differently upon encountering
 end-of-file.  Some versions don't evaluate the expression; many versions
-(including @command{gawk}) do.  Here is an example, due to Duncan Moore:
+(including @command{gawk}) do.  Here is an example, courtesy of Duncan Moore:
 
 @ignore
 Date: Sun, 01 Apr 2012 11:49:33 +0100
@@ -8105,7 +8247,7 @@ BEGIN @{
 
 @noindent
 Here, the side effect is the @samp{++c}.  Is @code{c} incremented if
-end of file is encountered, before the element in @code{a} is assigned?
+end-of-file is encountered before the element in @code{a} is assigned?
 
 @command{gawk} treats @code{getline} like a function call, and evaluates
 the expression @samp{a[++c]} before attempting to read from @file{f}.
@@ -8124,7 +8266,7 @@ and whether the variant is standard or a @command{gawk} extension.
 Note: for each variant, @command{gawk} sets the @code{RT} predefined variable.
 
 @float Table,table-getline-variants
-@caption{@code{getline} Variants and What They Set}
+@caption{@code{getline} variants and what they set}
 @multitable @columnfractions .33 .38 .27
 @headitem Variant @tab Effect @tab @command{awk} / @command{gawk}
 @item @code{getline} @tab Sets @code{$0}, @code{NF}, @code{FNR}, @code{NR}, and @code{RT} @tab @command{awk}
@@ -8137,12 +8279,9 @@ Note: for each variant, @command{gawk} sets the @code{RT} predefined variable.
 @item @var{command} @code{|& getline} @var{var} @tab Sets @var{var} and @code{RT} @tab @command{gawk}
 @end multitable
 @end float
-@c ENDOFRANGE getl
-@c ENDOFRANGE inex
-@c ENDOFRANGE infir
 
 @node Read Timeout
-@section Reading Input With A Timeout
+@section Reading Input with a Timeout
 @cindex timeout, reading input
 
 @cindex differences in @command{awk} and @command{gawk}, read timeouts
@@ -8150,8 +8289,8 @@ This @value{SECTION} describes a feature that is specific to @command{gawk}.
 
 You may specify a timeout in milliseconds for reading input from the keyboard,
 a pipe, or two-way communication, including TCP/IP sockets. This can be done
-on a per input, command or connection basis, by setting a special element
-in the @code{PROCINFO} array (@pxref{Auto-set}):
+on a per-input, per-command, or per-connection basis, by setting a special
+element in the @code{PROCINFO} array (@pxref{Auto-set}):
 
 @example
 PROCINFO["input_name", "READ_TIMEOUT"] = @var{timeout in milliseconds}
@@ -8182,7 +8321,7 @@ while ((getline < "/dev/stdin") > 0)
 @end example
 
 @command{gawk} terminates the read operation if input does not
-arrive after waiting for the timeout period, returns failure
+arrive after waiting for the timeout period, returns failure,
 and sets @code{ERRNO} to an appropriate string value.
 A negative or zero value for the timeout is the same as specifying
 no timeout at all.
@@ -8192,7 +8331,7 @@ loop that reads input records and matches them against patterns,
 like so:
 
 @example
-$ @kbd{ gawk 'BEGIN @{ PROCINFO["-", "READ_TIMEOUT"] = 5000 @}}
+$ @kbd{gawk 'BEGIN @{ PROCINFO["-", "READ_TIMEOUT"] = 5000 @}}
 > @kbd{@{ print "You entered: " $0 @}'}
 @kbd{gawk}
 @print{} You entered: gawk
@@ -8215,7 +8354,7 @@ for the input to arrive:
 PROCINFO[Service, "READ_TIMEOUT"] = 1000
 while ((Service |& getline) > 0) @{
     print $0
-    PROCINFO[S, "READ_TIMEOUT"] -= 100
+    PROCINFO[Service, "READ_TIMEOUT"] -= 100
 @}
 @end example
 
@@ -8224,21 +8363,22 @@ You should not assume that the read operation will block
 exactly after the tenth record has been printed. It is possible that
 @command{gawk} will read and buffer more than one record's
 worth of data the first time. Because of this, changing the value
-of timeout like in the above example is not very useful.
+of timeout like in the preceding example is not very useful.
 @end quotation
 
-If the @code{PROCINFO} element is not present and the environment
-variable @env{GAWK_READ_TIMEOUT} exists,
+If the @code{PROCINFO} element is not present and the
+@env{GAWK_READ_TIMEOUT} environment variable exists,
 @command{gawk} uses its value to initialize the timeout value.
 The exclusive use of the environment variable to specify timeout
 has the disadvantage of not being able to control it
-on a per command or connection basis.
+on a per-command or per-connection basis.
 
 @command{gawk} considers a timeout event to be an error even though
 the attempt to read from the underlying device may
 succeed in a later attempt. This is a limitation, and it also
 means that you cannot use this to multiplex input from
-two or more sources.
+two or more sources.  @DBXREF{Retrying Input} for a way to enable 
+later I/O attempts to succeed.
 
 Assigning a timeout value prevents read operations from
 blocking indefinitely. But bear in mind that there are other ways
@@ -8248,8 +8388,38 @@ a connection before it can start reading any data,
 or the attempt to open a FIFO special file for reading can block
 indefinitely until some other process opens it for writing.
 
+@node Retrying Input
+@section Retrying Reads After Certain Input Errors
+@cindex retrying input
+
+@cindex differences in @command{awk} and @command{gawk}, retrying input
+This @value{SECTION} describes a feature that is specific to @command{gawk}.
+
+When @command{gawk} encounters an error while reading input, by
+default @code{getline} returns @minus{}1, and subsequent attempts to
+read from that file result in an end-of-file indication.  However, you
+may optionally instruct @command{gawk} to allow I/O to be retried when
+certain errors are encountered by setting a special element in
+the @code{PROCINFO} array (@pxref{Auto-set}):
+
+@example
+PROCINFO["@var{input_name}", "RETRY"] = 1
+@end example
+
+When this element exists, @command{gawk} checks the value of the system
+(C language)
+@code{errno} variable when an I/O error occurs.  If @code{errno} indicates
+a subsequent I/O attempt may succeed, @code{getline} instead returns
+@minus{}2 and
+further calls to @code{getline} may succeed.  This applies to the @code{errno}
+values @code{EAGAIN}, @code{EWOULDBLOCK}, @code{EINTR}, or @code{ETIMEDOUT}.
+
+This feature is useful in conjunction with
+@code{PROCINFO["@var{input_name}", "READ_TIMEOUT"]} or situations where a file
+descriptor has been configured to behave in a non-blocking fashion.
+
 @node Command-line directories
-@section Directories On The Command Line
+@section Directories on the Command Line
 @cindex differences in @command{awk} and @command{gawk}, command-line directories
 @cindex directories, command-line
 @cindex command line, directories on
@@ -8264,14 +8434,14 @@ command line, but otherwise ignores it.  This makes it easier to use
 shell wildcards with your @command{awk} program:
 
 @example
-$ @kbd{gawk -f whizprog.awk *}        @ii{Directories could kill this progam}
+$ @kbd{gawk -f whizprog.awk *}        @ii{Directories could kill this program}
 @end example
 
 If either of the @option{--posix}
 or @option{--traditional} options is given, then @command{gawk} reverts
 to treating a directory on the command line as a fatal error.
 
-@xref{Extension Sample Readdir}, for a way to treat directories
+@DBXREF{Extension Sample Readdir} for a way to treat directories
 as usable data from an @command{awk} program.
 
 @node Input Summary
@@ -8283,7 +8453,7 @@ Input is split into records based on the value of @code{RS}.
 The possibilities are as follows:
 
 @multitable @columnfractions .25 .35 .40
-@headitem Value of @code{RS} @tab Records are split on @tab @command{awk} / @command{gawk}
+@headitem Value of @code{RS} @tab Records are split on @dots{} @tab @command{awk} / @command{gawk}
 @item Any single character @tab That character @tab @command{awk}
 @item The empty string (@code{""}) @tab Runs of two or more newlines @tab @command{awk}
 @item A regexp @tab Text that matches the regexp @tab @command{gawk}
@@ -8298,7 +8468,7 @@ The possibilities are as follows:
 
 @item
 After splitting the input into records, @command{awk} further splits
-the record into individual fields, named @code{$1}, @code{$2} and so
+the records into individual fields, named @code{$1}, @code{$2}, and so
 on. @code{$0} is the whole record, and @code{NF} indicates how many
 fields there are.  The default way to split fields is between whitespace
 characters.
@@ -8312,14 +8482,14 @@ greater than @code{NF} creates the field and rebuilds the record, using
 thing. Decrementing @code{NF} throws away fields and rebuilds the record.
 
 @item
-Field splitting is more complicated than record splitting.
+Field splitting is more complicated than record splitting:
 
-@multitable @columnfractions .40 .45 .15
+@multitable @columnfractions .40 .40 .20
 @headitem Field separator value @tab Fields are split @dots{} @tab @command{awk} / @command{gawk}
 @item @code{FS == " "} @tab On runs of whitespace @tab @command{awk}
 @item @code{FS == @var{any single character}} @tab On that character @tab @command{awk}
 @item @code{FS == @var{regexp}} @tab On text matching the regexp @tab @command{awk}
-@item @code{FS == ""}  @tab Each individual character is a separate field @tab @command{gawk}
+@item @code{FS == ""}  @tab Such that each individual character is a separate field @tab @command{gawk}
 @item @code{FIELDWIDTHS == @var{list of columns}} @tab Based on character position @tab @command{gawk}
 @item @code{FPAT == @var{regexp}} @tab On the text surrounding text matching the regexp @tab @command{gawk}
 @end multitable
@@ -8336,11 +8506,11 @@ This can also be done using command-line variable assignment.
 Use @code{PROCINFO["FS"]} to see how fields are being split.
 
 @item
-Use @code{getline} in its various forms to read additional records,
+Use @code{getline} in its various forms to read additional records
 from the default input stream, from a file, or from a pipe or coprocess.
 
 @item
-Use @code{PROCINFO[@var{file}, "READ_TIMEOUT"]} to cause reads to timeout
+Use @code{PROCINFO[@var{file}, "READ_TIMEOUT"]} to cause reads to time out
 for @var{file}.
 
 @item
@@ -8374,7 +8544,6 @@ That can be fixed by making one simple change. What is it?
 @node Printing
 @chapter Printing Output
 
-@c STARTOFRANGE prnt
 @cindex printing
 @cindex output, printing, See printing
 One of the most common programming actions is to @dfn{print}, or output,
@@ -8385,12 +8554,11 @@ The @code{print} statement is not limited when
 computing @emph{which} values to print. However, with two exceptions,
 you cannot specify @emph{how} to print them---how many
 columns, whether to use exponential notation or not, and so on.
-(For the exceptions, @pxref{Output Separators}, and
+(For the exceptions, @DBPXREF{Output Separators} and
 @ref{OFMT}.)
 For printing with specifications, you need the @code{printf} statement
 (@pxref{Printf}).
 
-@c STARTOFRANGE prnts
 @cindex @code{print} statement
 @cindex @code{printf} statement
 Besides basic and formatted printing, this @value{CHAPTER}
@@ -8411,6 +8579,7 @@ and discusses the @code{close()} built-in function.
                                 @command{gawk} allows access to inherited file
                                 descriptors.
 * Close Files And Pipes::       Closing Input and Output Files and Pipes.
+* Nonfatal::                    Enabling Nonfatal Output.
 * Output Summary::              Output summary.
 * Output Exercises::            Exercises.
 @end menu
@@ -8451,7 +8620,7 @@ space is printed between any two items.
 
 Note that the @code{print} statement is a statement and not an
 expression---you can't use it in the pattern part of a
-@var{pattern}-@var{action} statement, for example.
+pattern--action statement, for example.
 
 @node Print Examples
 @section @code{print} Statement Examples
@@ -8570,7 +8739,6 @@ You can continue either a @code{print} or
 @code{printf} statement simply by putting a newline after any comma
 (@pxref{Statements/Lines}).
 @end quotation
-@c ENDOFRANGE prnts
 
 @node Output Separators
 @section Output Separators
@@ -8582,14 +8750,14 @@ separated by single spaces.  However, this doesn't need to be the case;
 a single space is simply the default.  Any string of
 characters may be used as the @dfn{output field separator} by setting the
 predefined variable @code{OFS}.  The initial value of this variable
-is the string @w{@code{" "}}---that is, a single space.
+is the string @w{@code{" "}} (i.e., a single space).
 
-The output from an entire @code{print} statement is called an
-@dfn{output record}.  Each @code{print} statement outputs one output
-record, and then outputs a string called the @dfn{output record separator}
-(or @code{ORS}).  The initial
-value of @code{ORS} is the string @code{"\n"}; i.e., a newline
-character.  Thus, each @code{print} statement normally makes a separate line.
+The output from an entire @code{print} statement is called an @dfn{output
+record}.  Each @code{print} statement outputs one output record, and
+then outputs a string called the @dfn{output record separator} (or
+@code{ORS}).  The initial value of @code{ORS} is the string @code{"\n"}
+(i.e., a newline character).  Thus, each @code{print} statement normally
+makes a separate line.
 
 @cindex output, records
 @cindex output record separator, See @code{ORS} variable
@@ -8612,27 +8780,27 @@ newline:
 $ @kbd{awk 'BEGIN @{ OFS = ";"; ORS = "\n\n" @}}
 >            @kbd{@{ print $1, $2 @}' mail-list}
 @print{} Amelia;555-5553
-@print{} 
+@print{}
 @print{} Anthony;555-3412
-@print{} 
+@print{}
 @print{} Becky;555-7685
-@print{} 
+@print{}
 @print{} Bill;555-1675
-@print{} 
+@print{}
 @print{} Broderick;555-0542
-@print{} 
+@print{}
 @print{} Camilla;555-2912
-@print{} 
+@print{}
 @print{} Fabius;555-1234
-@print{} 
+@print{}
 @print{} Julie;555-6699
-@print{} 
+@print{}
 @print{} Martin;555-6480
-@print{} 
+@print{}
 @print{} Samuel;555-3430
-@print{} 
+@print{}
 @print{} Jean-Paul;555-2127
-@print{} 
+@print{}
 @end example
 
 If the value of @code{ORS} does not contain a newline, the program's output
@@ -8643,7 +8811,7 @@ runs together on a single line.
 @cindex numeric, output format
 @cindex formats@comma{} numeric output
 When printing numeric values with the @code{print} statement,
-@command{awk} internally converts the number to a string of characters
+@command{awk} internally converts each number to a string of characters
 and prints that string.  @command{awk} uses the @code{sprintf()} function
 to do this conversion
 (@pxref{String Functions}).
@@ -8683,7 +8851,6 @@ if @code{OFMT} contains anything but a floating-point conversion specification.
 @node Printf
 @section Using @code{printf} Statements for Fancier Printing
 
-@c STARTOFRANGE printfs
 @cindex @code{printf} statement
 @cindex output, formatted
 @cindex formatting output
@@ -8713,9 +8880,9 @@ printf @var{format}, @var{item1}, @var{item2}, @dots{}
 @end example
 
 @noindent
-As print @code{print}, the entire list of arguments may optionally be
+As for @code{print}, the entire list of arguments may optionally be
 enclosed in parentheses. Here too, the parentheses are necessary if any
-of the item expressions use the @samp{>} relational operator; otherwise,
+of the item expressions uses the @samp{>} relational operator; otherwise,
 it can be confused with an output redirection (@pxref{Redirection}).
 
 @cindex format specifiers
@@ -8746,7 +8913,7 @@ $ @kbd{awk 'BEGIN @{}
 @end example
 
 @noindent
-Here, neither the @samp{+} nor the @samp{OUCH} appear in
+Here, neither the @samp{+} nor the @samp{OUCH!} appears in
 the output message.
 
 @node Control Letters
@@ -8790,11 +8957,11 @@ a single byte (0--255).
 @item @code{%d}, @code{%i}
 Print a decimal integer.
 The two control letters are equivalent.
-(The @code{%i} specification is for compatibility with ISO C.)
+(The @samp{%i} specification is for compatibility with ISO C.)
 
 @item @code{%e}, @code{%E}
-Print a number in scientific (exponential) notation;
-for example:
+Print a number in scientific (exponential) notation.
+For example:
 
 @example
 printf "%4.3e\n", 1950
@@ -8805,7 +8972,7 @@ prints @samp{1.950e+03}, with a total of four significant figures, three of
 which follow the decimal point.
 (The @samp{4.3} represents two modifiers,
 discussed in the next @value{SUBSECTION}.)
-@code{%E} uses @samp{E} instead of @samp{e} in the output.
+@samp{%E} uses @samp{E} instead of @samp{e} in the output.
 
 @item @code{%f}
 Print a number in floating-point notation.
@@ -8821,26 +8988,26 @@ which follow the decimal point.
 (The @samp{4.3} represents two modifiers,
 discussed in the next @value{SUBSECTION}.)
 
-On systems supporting IEEE 754 floating point format, values
+On systems supporting IEEE 754 floating-point format, values
 representing negative
 infinity are formatted as
 @samp{-inf} or @samp{-infinity},
 and positive infinity as
-@samp{inf} and @samp{infinity}.
+@samp{inf} or @samp{infinity}.
 The special ``not a number'' value formats as @samp{-nan} or @samp{nan}
 (@pxref{Math Definitions}).
 
 @item @code{%F}
-Like @code{%f} but the infinity and ``not a number'' values are spelled
+Like @samp{%f}, but the infinity and ``not a number'' values are spelled
 using uppercase letters.
 
-The @code{%F} format is a POSIX extension to ISO C; not all systems
-support it.  On those that don't, @command{gawk} uses @code{%f} instead.
+The @samp{%F} format is a POSIX extension to ISO C; not all systems
+support it.  On those that don't, @command{gawk} uses @samp{%f} instead.
 
 @item @code{%g}, @code{%G}
 Print a number in either scientific notation or in floating-point
 notation, whichever uses fewer characters; if the result is printed in
-scientific notation, @code{%G} uses @samp{E} instead of @samp{e}.
+scientific notation, @samp{%G} uses @samp{E} instead of @samp{e}.
 
 @item @code{%o}
 Print an unsigned octal integer
@@ -8852,11 +9019,11 @@ Print a string.
 @item @code{%u}
 Print an unsigned decimal integer.
 (This format is of marginal use, because all numbers in @command{awk}
-are floating-point; it is provided primarily for compatibility with C.)
+are floating point; it is provided primarily for compatibility with C.)
 
 @item @code{%x}, @code{%X}
 Print an unsigned hexadecimal integer;
-@code{%X} uses the letters @samp{A} through @samp{F}
+@samp{%X} uses the letters @samp{A} through @samp{F}
 instead of @samp{a} through @samp{f}
 (@pxref{Nondecimal-numbers}).
 
@@ -8871,7 +9038,7 @@ argument and it ignores any modifiers.
 @quotation NOTE
 When using the integer format-control letters for values that are
 outside the range of the widest C integer type, @command{gawk} switches to
-the @code{%g} format specifier. If @option{--lint} is provided on the
+the @samp{%g} format specifier. If @option{--lint} is provided on the
 command line (@pxref{Options}), @command{gawk}
 warns about this.  Other versions of @command{awk} may print invalid
 values or do something else entirely.
@@ -8881,7 +9048,6 @@ values or do something else entirely.
 @node Format Modifiers
 @subsection Modifiers for @code{printf} Formats
 
-@c STARTOFRANGE pfm
 @cindex @code{printf} statement, modifiers
 @cindex modifiers@comma{} in format specifiers
 A format specification can also include @dfn{modifiers} that can control
@@ -8892,12 +9058,12 @@ represent
 spaces in the output. Here are the possible modifiers, in the order in
 which they may appear:
 
-@table @code
+@table @asis
 @cindex differences in @command{awk} and @command{gawk}, @code{print}/@code{printf} statements
 @cindex @code{printf} statement, positional specifiers
 @c the code{} does NOT start a secondary
 @cindex positional specifiers, @code{printf} statement
-@item @var{N}$
+@item @code{@var{N}$}
 An integer constant followed by a @samp{$} is a @dfn{positional specifier}.
 Normally, format specifications are applied to arguments in the order
 given in the format string.  With a positional specifier, the format
@@ -8920,7 +9086,7 @@ messages at runtime.
 which describes how and why to use positional specifiers.
 For now, we ignore them.
 
-@item -
+@item @code{-} (Minus)
 The minus sign, used before the width modifier (see later on in
 this list),
 says to left-justify
@@ -8938,31 +9104,31 @@ prints @samp{foo@bullet{}}.
 For numeric conversions, prefix positive values with a space and
 negative values with a minus sign.
 
-@item +
+@item @code{+}
 The plus sign, used before the width modifier (see later on in
 this list),
 says to always supply a sign for numeric conversions, even if the data
 to format is positive. The @samp{+} overrides the space modifier.
 
-@item #
-Use an ``alternate form'' for certain control letters.
-For @code{%o}, supply a leading zero.
-For @code{%x} and @code{%X}, supply a leading @code{0x} or @samp{0X} for
+@item @code{#}
+Use an ``alternative form'' for certain control letters.
+For @samp{%o}, supply a leading zero.
+For @samp{%x} and @samp{%X}, supply a leading @samp{0x} or @samp{0X} for
 a nonzero result.
-For @code{%e}, @code{%E}, @code{%f}, and @code{%F}, the result always
+For @samp{%e}, @samp{%E}, @samp{%f}, and @samp{%F}, the result always
 contains a decimal point.
-For @code{%g} and @code{%G}, trailing zeros are not removed from the result.
+For @samp{%g} and @samp{%G}, trailing zeros are not removed from the result.
 
-@item 0
+@item @code{0}
 A leading @samp{0} (zero) acts as a flag indicating that output should be
 padded with zeros instead of spaces.
 This applies only to the numeric output formats.
 This flag only has an effect when the field width is wider than the
 value to print.
 
-@item '
+@item @code{'}
 A single quote or apostrophe character is a POSIX extension to ISO C.
-It indicates that the integer part of a floating point value, or the
+It indicates that the integer part of a floating-point value, or the
 entire part of an integer decimal value, should have a thousands-separator
 character in it.  This only works in locales that support such characters.
 For example:
@@ -9013,7 +9179,7 @@ prints @samp{foobar}.
 Preceding the @var{width} with a minus sign causes the output to be
 padded with spaces on the right, instead of on the left.
 
-@item .@var{prec}
+@item @code{.@var{prec}}
 A period followed by an integer constant
 specifies the precision to use when printing.
 The meaning of the precision varies by control letter:
@@ -9043,7 +9209,7 @@ prints @samp{foob}.
 @end table
 
 The C library @code{printf}'s dynamic @var{width} and @var{prec}
-capability (for example, @code{"%*.*s"}) is supported.  Instead of
+capability (e.g., @code{"%*.*s"}) is supported.  Instead of
 supplying explicit @var{width} and/or @var{prec} values in the format
 string, they are passed in the argument list.  For example:
 
@@ -9076,7 +9242,7 @@ printf "%" w "." p "s\n", s
 @end example
 
 @noindent
-This is not particularly easy to read but it does work.
+This is not particularly easy to read, but it does work.
 
 @c @cindex lint checks
 @cindex troubleshooting, fatal errors, @code{printf} format strings
@@ -9087,7 +9253,6 @@ format strings. These are not valid in @command{awk}.  Most @command{awk}
 implementations silently ignore them.  If @option{--lint} is provided
 on the command line (@pxref{Options}), @command{gawk} warns about their
 use. If @option{--posix} is supplied, their use is a fatal error.
-@c ENDOFRANGE pfm
 
 @node Printf Examples
 @subsection Examples Using @code{printf}
@@ -9123,7 +9288,7 @@ $ @kbd{awk '@{ printf "%-10s %s\n", $1, $2 @}' mail-list}
 @end example
 
 In this case, the phone numbers had to be printed as strings because
-the numbers are separated by a dash.  Printing the phone numbers as
+the numbers are separated by dashes.  Printing the phone numbers as
 numbers would have produced just the first three digits: @samp{555}.
 This would have been pretty confusing.
 
@@ -9143,7 +9308,7 @@ awk 'BEGIN @{ print "Name      Number"
            @{ printf "%-10s %s\n", $1, $2 @}' mail-list
 @end example
 
-The above example mixes @code{print} and @code{printf} statements in
+The preceding example mixes @code{print} and @code{printf} statements in
 the same program.  Using just @code{printf} statements can produce the
 same results:
 
@@ -9168,14 +9333,11 @@ awk 'BEGIN @{ format = "%-10s %s\n"
            @{ printf format, $1, $2 @}' mail-list
 @end example
 
-@c ENDOFRANGE printfs
 
 @node Redirection
 @section Redirecting Output of @code{print} and @code{printf}
 
-@c STARTOFRANGE outre
 @cindex output redirection
-@c STARTOFRANGE reout
 @cindex redirection of output
 @cindex @option{--sandbox} option, output redirection with @code{print}, @code{printf}
 So far, the output from @code{print} and @code{printf} has gone
@@ -9186,7 +9348,7 @@ This is called @dfn{redirection}.
 
 @quotation NOTE
 When @option{--sandbox} is specified (@pxref{Options}),
-redirecting output to files, pipes and coprocesses is disabled.
+redirecting output to files, pipes, and coprocesses is disabled.
 @end quotation
 
 A redirection appears after the @code{print} or @code{printf} statement.
@@ -9239,7 +9401,7 @@ Each output file contains one name or number per line.
 @cindex @code{>} (right angle bracket), @code{>>} operator (I/O)
 @cindex right angle bracket (@code{>}), @code{>>} operator (I/O)
 @item print @var{items} >> @var{output-file}
-This redirection prints the items into the pre-existing output file
+This redirection prints the items into the preexisting output file
 named @var{output-file}.  The difference between this and the
 single-@samp{>} redirection is that the old contents (if any) of
 @var{output-file} are not erased.  Instead, the @command{awk} output is
@@ -9278,7 +9440,7 @@ The unsorted list is written with an ordinary redirection, while
 the sorted list is written by piping through the @command{sort} utility.
 
 The next example uses redirection to mail a message to the mailing
-list @samp{bug-system}.  This might be useful when trouble is encountered
+list @code{bug-system}.  This might be useful when trouble is encountered
 in an @command{awk} script run periodically for system maintenance:
 
 @example
@@ -9290,7 +9452,7 @@ close(report)
 
 The @code{close()} function is called here because it's a good idea to close
 the pipe as soon as all the intended output has been sent to it.
-@xref{Close Files And Pipes},
+@DBXREF{Close Files And Pipes}
 for more information.
 
 This example also illustrates the use of a variable to represent
@@ -9309,15 +9471,23 @@ This redirection prints the items to the input of @var{command}.
 The difference between this and the
 single-@samp{|} redirection is that the output from @var{command}
 can be read with @code{getline}.
-Thus @var{command} is a @dfn{coprocess}, which works together with,
-but subsidiary to, the @command{awk} program.
+Thus, @var{command} is a @dfn{coprocess}, which works together with
+but is subsidiary to the @command{awk} program.
 
 This feature is a @command{gawk} extension, and is not available in
 POSIX @command{awk}.
+@ifnotdocbook
 @xref{Getline/Coprocess},
 for a brief discussion.
 @xref{Two-way I/O},
 for a more complete discussion.
+@end ifnotdocbook
+@ifdocbook
+@DBXREF{Getline/Coprocess}
+for a brief discussion and
+@DBREF{Two-way I/O}
+for a more complete discussion.
+@end ifdocbook
 @end table
 
 Redirecting output using @samp{>}, @samp{>>}, @samp{|}, or @samp{|&}
@@ -9340,9 +9510,9 @@ print "Avoid improbability generators" >> "guide.txt"
 @noindent
 This is indeed how redirections must be used from the shell.  But in
 @command{awk}, it isn't necessary.  In this kind of case, a program should
-use @samp{>} for all the @code{print} statements, since the output file
+use @samp{>} for all the @code{print} statements, because the output file
 is only opened once. (It happens that if you mix @samp{>} and @samp{>>}
-that output is produced in the expected order. However, mixing the operators
+output is produced in the expected order. However, mixing the operators
 for the same file is definitely poor style, and is confusing to readers
 of your program.)
 
@@ -9389,14 +9559,12 @@ The program builds up a list of command lines,
 using the @command{mv} utility to rename the files.
 It then sends the list to the shell for execution.
 
-@xref{Shell Quoting}, for a function that can help in generating
+@DBXREF{Shell Quoting} for a function that can help in generating
 command lines to be fed to the shell.
 @end sidebar
-@c ENDOFRANGE outre
-@c ENDOFRANGE reout
 
 @node Special FD
-@section Special Files for Standard Pre-Opened Data Streams
+@section Special Files for Standard Preopened Data Streams
 @cindex standard input
 @cindex input, standard
 @cindex standard output
@@ -9409,7 +9577,7 @@ command lines to be fed to the shell.
 Running programs conventionally have three input and output streams
 already available to them for reading and writing.  These are known
 as the @dfn{standard input}, @dfn{standard output}, and @dfn{standard
-error output}.  These open streams (and any other open file or pipe)
+error output}.  These open streams (and any other open files or pipes)
 are often referred to by the technical term @dfn{file descriptors}.
 
 These streams are, by default, connected to your keyboard and screen, but
@@ -9447,14 +9615,14 @@ that is connected to your keyboard and screen. It represents the
 ``terminal,''@footnote{The ``tty'' in @file{/dev/tty} stands for
 ``Teletype,'' a serial terminal.} which on modern systems is a keyboard
 and screen, not a serial console.)
-This generally has the same effect but not always: although the
+This generally has the same effect, but not always: although the
 standard error stream is usually the screen, it can be redirected; when
 that happens, writing to the screen is not correct.  In fact, if
 @command{awk} is run from a background job, it may not have a
 terminal at all.
 Then opening @file{/dev/tty} fails.
 
-@command{gawk}, BWK @command{awk} and @command{mawk} provide
+@command{gawk}, BWK @command{awk}, and @command{mawk} provide
 special @value{FN}s for accessing the three standard streams.
 If the @value{FN} matches one of these special names when @command{gawk}
 (or one of the others) redirects input or output, then it directly uses
@@ -9492,21 +9660,20 @@ print "Serious error detected!" > "/dev/stderr"
 
 @cindex troubleshooting, quotes with file names
 Note the use of quotes around the @value{FN}.
-Like any other redirection, the value must be a string.
+Like with any other redirection, the value must be a string.
 It is a common error to omit the quotes, which leads
 to confusing results.
 
 @command{gawk} does not treat these @value{FN}s as special when
-in POSIX compatibility mode. However, since BWK @command{awk}
+in POSIX-compatibility mode. However, because BWK @command{awk}
 supports them, @command{gawk} does support them even when
 invoked with the @option{--traditional} option (@pxref{Options}).
 
 @node Special Files
 @section Special @value{FFN}s in @command{gawk}
-@c STARTOFRANGE gfn
 @cindex @command{gawk}, file names in
 
-Besides access to standard input, stanard output, and standard error,
+Besides access to standard input, standard output, and standard error,
 @command{gawk} provides access to any open file descriptor.
 Additionally, there are special @value{FN}s reserved for
 TCP/IP networking.
@@ -9519,7 +9686,7 @@ TCP/IP networking.
 @end menu
 
 @node Other Inherited Files
-@subsection Accessing Other Open Files With @command{gawk}
+@subsection Accessing Other Open Files with @command{gawk}
 
 Besides the @code{/dev/stdin}, @code{/dev/stdout}, and @code{/dev/stderr}
 special @value{FN}s mentioned earlier, @command{gawk} provides syntax
@@ -9555,7 +9722,7 @@ This is done using a special @value{FN} of the form:
 @file{/@var{net-type}/@var{protocol}/@var{local-port}/@var{remote-host}/@var{remote-port}}
 @end example
 
-The @var{net-type} is one of @samp{inet}, @samp{inet4} or @samp{inet6}.
+The @var{net-type} is one of @samp{inet}, @samp{inet4}, or @samp{inet6}.
 The @var{protocol} is one of @samp{tcp} or @samp{udp},
 and the other fields represent the other essential pieces of information
 for making a networking connection.
@@ -9576,7 +9743,7 @@ special @value{FN}s that @command{gawk} provides:
 @cindex compatibility mode (@command{gawk}), file names
 @cindex file names, in compatibility mode
 @item
-Recognition of the @value{FN}s for the three standard pre-opened
+Recognition of the @value{FN}s for the three standard preopened
 files is disabled only in POSIX mode.
 
 @item
@@ -9589,23 +9756,18 @@ compatibility mode (either @option{--traditional} or @option{--posix};
 interprets these special @value{FN}s.
 For example, using @samp{/dev/fd/4}
 for output actually writes on file descriptor 4, and not on a new
-file descriptor that is @code{dup()}'ed from file descriptor 4.  Most of
+file descriptor that is @code{dup()}ed from file descriptor 4.  Most of
 the time this does not matter; however, it is important to @emph{not}
 close any of the files related to file descriptors 0, 1, and 2.
 Doing so results in unpredictable behavior.
 @end itemize
-@c ENDOFRANGE gfn
 
 @node Close Files And Pipes
 @section Closing Input and Output Redirections
 @cindex files, output, See output files
-@c STARTOFRANGE ifc
 @cindex input files, closing
-@c STARTOFRANGE ofc
 @cindex output, files@comma{} closing
-@c STARTOFRANGE pc
 @cindex pipe, closing
-@c STARTOFRANGE cc
 @cindex coprocesses, closing
 @cindex @code{getline} command, coprocesses@comma{} using from
 
@@ -9744,7 +9906,7 @@ is not closed and released until @code{close()} is called or
 @command{awk} exits.
 
 @code{close()} silently does nothing if given an argument that
-does not represent a file, pipe or coprocess that was opened with
+does not represent a file, pipe, or coprocess that was opened with
 a redirection.  In such a case, it returns a negative value,
 indicating an error. In addition, @command{gawk} sets @code{ERRNO}
 to a string indicating the error.
@@ -9778,9 +9940,10 @@ which describes it in more detail and gives an example.
 @cindex Unix @command{awk}, @code{close()} function and
 
 In many older versions of Unix @command{awk}, the @code{close()} function
-is actually a statement.  It is a syntax error to try and use the return
-value from @code{close()}:
+is actually a statement.
 @value{DARKCORNER}
+It is a syntax error to try and use the return
+value from @code{close()}:
 
 @example
 command = "@dots{}"
@@ -9810,18 +9973,79 @@ This value is zero if the close succeeds, or @minus{}1 if
 it fails.
 
 The POSIX standard is very vague; it says that @code{close()}
-returns zero on success and nonzero otherwise.  In general,
+returns zero on success and a nonzero value otherwise.  In general,
 different implementations vary in what they report when closing
-pipes; thus the return value cannot be used portably.
+pipes; thus, the return value cannot be used portably.
 @value{DARKCORNER}
 In POSIX mode (@pxref{Options}), @command{gawk} just returns zero
 when closing a pipe.
 @end sidebar
 
-@c ENDOFRANGE ifc
-@c ENDOFRANGE ofc
-@c ENDOFRANGE pc
-@c ENDOFRANGE cc
+
+@node Nonfatal
+@section Enabling Nonfatal Output
+
+This @value{SECTION} describes a @command{gawk}-specific feature.
+
+In standard @command{awk}, output with @code{print} or @code{printf}
+to a nonexistent file, or some other I/O error (such as filling up the
+disk) is a fatal error.
+
+@example
+$ @kbd{gawk 'BEGIN @{ print "hi" > "/no/such/file" @}'}
+@error{} gawk: cmd. line:1: fatal: can't redirect to `/no/such/file' (No such file or directory)
+@end example
+
+@command{gawk} makes it possible to detect that an error has
+occurred, allowing you to possibly recover from the error, or
+at least print an error message of your choosing before exiting.
+You can do this in one of two ways:
+
+@itemize @bullet
+@item
+For all output files, by assigning any value to @code{PROCINFO["NONFATAL"]}.
+
+@item
+On a per-file basis, by assigning any value to
+@code{PROCINFO[@var{filename}, "NONFATAL"]}.
+Here, @var{filename} is the name of the file to which
+you wish output to be nonfatal.
+@end itemize
+
+Once you have enabled nonfatal output, you must check @code{ERRNO}
+after every relevant @code{print} or @code{printf} statement to
+see if something went wrong.  It is also a good idea to initialize
+@code{ERRNO} to zero before attempting the output. For example:
+
+@example
+$ @kbd{gawk '}
+> @kbd{BEGIN @{}
+> @kbd{    PROCINFO["NONFATAL"] = 1}
+> @kbd{    ERRNO = 0}
+> @kbd{    print "hi" > "/no/such/file"}
+> @kbd{    if (ERRNO) @{}
+> @kbd{        print("Output failed:", ERRNO) > "/dev/stderr"}
+> @kbd{        exit 1}
+> @kbd{    @}}
+> @kbd{@}'}
+@error{} Output failed: No such file or directory
+@end example
+
+Here, @command{gawk} did not produce a fatal error; instead
+it let the @command{awk} program code detect the problem and handle it.
+
+This mechanism works also for standard output and standard error.
+For standard output, you may use @code{PROCINFO["-", "NONFATAL"]}
+or @code{PROCINFO["/dev/stdout", "NONFATAL"]}.  For standard error, use
+@code{PROCINFO["/dev/stderr", "NONFATAL"]}.
+
+When attempting to open a TCP/IP socket (@pxref{TCP/IP Networking}),
+@command{gawk} tries multiple times. The @env{GAWK_SOCK_RETRIES}
+environment variable (@pxref{Other Environment Variables}) allows you to
+override @command{gawk}'s builtin default number of attempts.  However,
+once nonfatal I/O is enabled for a given socket, @command{gawk} only
+retries once, relying on @command{awk}-level code to notice that there
+was a problem.
 
 @node Output Summary
 @section Summary
@@ -9835,22 +10059,28 @@ for numeric values for the @code{print} statement.
 
 @item
 The @code{printf} statement provides finer-grained control over output,
-with format control letters for different data types and various flags
-that modify the behavior of the format control letters.
+with format-control letters for different data types and various flags
+that modify the behavior of the format-control letters.
 
 @item
 Output from both @code{print} and @code{printf} may be redirected to
 files, pipes, and coprocesses.
 
 @item
-@command{gawk} provides special file names for access to standard input,
-output and error, and for network communications.
+@command{gawk} provides special @value{FN}s for access to standard input,
+output, and error, and for network communications.
 
 @item
-Use @code{close()} to close open file, pipe and coprocess redirections.
+Use @code{close()} to close open file, pipe, and coprocess redirections.
 For coprocesses, it is possible to close only one direction of the
 communications.
 
+@item
+Normally errors with @code{print} or @code{printf} are fatal.
+@command{gawk} lets you make output errors be nonfatal either for
+all files or on a per-file basis. You must then check for errors
+after every relevant output statement.
+
 @end itemize
 
 @c EXCLUDE START
@@ -9885,11 +10115,9 @@ BEGIN @{ print "Serious error detected!" > /dev/stderr @}
 @end enumerate
 @c EXCLUDE END
 
-@c ENDOFRANGE prnt
 
 @node Expressions
 @chapter Expressions
-@c STARTOFRANGE exps
 @cindex expressions
 
 Expressions are the basic building blocks of @command{awk} patterns
@@ -9900,7 +10128,7 @@ can assign a new value to a variable or a field by using an assignment operator.
 An expression can serve as a pattern or action statement on its own.
 Most other kinds of
 statements contain one or more expressions that specify the data on which to
-operate.  As in other languages, expressions in @command{awk} include
+operate.  As in other languages, expressions in @command{awk} can include
 variables, array references, constants, and function calls, as well as
 combinations of these with various operators.
 
@@ -9915,11 +10143,11 @@ combinations of these with various operators.
 @end menu
 
 @node Values
-@section Constants, Variables and Conversions
+@section Constants, Variables, and Conversions
 
 Expressions are built up from values and the operations performed
 upon them. This @value{SECTION} describes the elementary objects
-which provide the values used in expressions.
+that provide the values used in expressions.
 
 @menu
 * Constants::                   String, numeric and regexp constants.
@@ -9932,7 +10160,6 @@ which provide the values used in expressions.
 @node Constants
 @subsection Constant Expressions
 
-@c STARTOFRANGE cnst
 @cindex constants, types of
 
 The simplest type of expression is the @dfn{constant}, which always has
@@ -9941,7 +10168,7 @@ string, and regular expression.
 
 Each is used in the appropriate context when you need a data
 value that isn't going to change.  Numeric constants can
-have different forms, but are stored identically internally.
+have different forms, but are internally stored in an identical manner.
 
 @menu
 * Scalar Constants::            Numeric and string constants.
@@ -9957,7 +10184,7 @@ have different forms, but are stored identically internally.
 A @dfn{numeric constant} stands for a number.  This number can be an
 integer, a decimal fraction, or a number in scientific (exponential)
 notation.@footnote{The internal representation of all numbers,
-including integers, uses double precision floating-point numbers.
+including integers, uses double-precision floating-point numbers.
 On most modern systems, these are in IEEE 754 standard format.
 @xref{Arbitrary Precision Arithmetic}, for much more information.}
 Here are some examples of numeric constants that all
@@ -9970,8 +10197,8 @@ have the same value:
 @end example
 
 @cindex string constants
-A string constant consists of a sequence of characters enclosed in
-double-quotation marks.  For example:
+A @dfn{string constant} consists of a sequence of characters enclosed in
+double quotation marks.  For example:
 
 @example
 "parrot"
@@ -9982,7 +10209,7 @@ double-quotation marks.  For example:
 @cindex strings, length limitations
 represents the string whose contents are @samp{parrot}.  Strings in
 @command{gawk} can be of any length, and they can contain any of the possible
-eight-bit ASCII characters including ASCII @value{NUL} (character code zero).
+eight-bit ASCII characters, including ASCII @sc{nul} (character code zero).
 Other @command{awk}
 implementations may have difficulty with some character codes.
 
@@ -9993,19 +10220,19 @@ implementations may have difficulty with some character codes.
 @cindex numbers, octal
 @cindex numbers, hexadecimal
 
-In @command{awk}, all numbers are in decimal; i.e., base 10.  Many other
+In @command{awk}, all numbers are in decimal (i.e., base 10).  Many other
 programming languages allow you to specify numbers in other bases, often
 octal (base 8) and hexadecimal (base 16).
-In octal, the numbers go 0, 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, etc.
-Just as @samp{11}, in decimal, is 1 times 10 plus 1, so
-@samp{11}, in octal, is 1 times 8, plus 1. This equals 9 in decimal.
-In hexadecimal, there are 16 digits. Since the everyday decimal
+In octal, the numbers go 0, 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, and so on.
+Just as @samp{11} in decimal is 1 times 10 plus 1, so
+@samp{11} in octal is 1 times 8 plus 1. This equals 9 in decimal.
+In hexadecimal, there are 16 digits. Because the everyday decimal
 number system only has ten digits (@samp{0}--@samp{9}), the letters
 @samp{a} through @samp{f} are used to represent the rest.
 (Case in the letters is usually irrelevant; hexadecimal @samp{a} and @samp{A}
 have the same value.)
-Thus, @samp{11}, in
-hexadecimal, is 1 times 16 plus 1, which equals 17 in decimal.
+Thus, @samp{11} in
+hexadecimal is 1 times 16 plus 1, which equals 17 in decimal.
 
 Just by looking at plain @samp{11}, you can't tell what base it's in.
 So, in C, C++, and other languages derived from C,
@@ -10016,13 +10243,13 @@ and hexadecimal numbers start with a leading @samp{0x} or @samp{0X}:
 
 @table @code
 @item 11
-Decimal value 11.
+Decimal value 11
 
 @item 011
-Octal 11, decimal value 9.
+Octal 11, decimal value 9
 
 @item 0x11
-Hexadecimal 11, decimal value 17.
+Hexadecimal 11, decimal value 17
 @end table
 
 This example shows the difference:
@@ -10050,12 +10277,13 @@ you can use the @code{strtonum()} function
 (@pxref{String Functions})
 to convert the data into a number.
 Most of the time, you will want to use octal or hexadecimal constants
-when working with the built-in bit manipulation functions;
-see @ref{Bitwise Functions},
+when working with the built-in bit-manipulation functions;
+see @DBREF{Bitwise Functions}
 for more information.
 
-Unlike some early C implementations, @samp{8} and @samp{9} are not valid
-in octal constants; e.g., @command{gawk} treats @samp{018} as decimal 18:
+Unlike in some early C implementations, @samp{8} and @samp{9} are not
+valid in octal constants.  For example, @command{gawk} treats @samp{018}
+as decimal 18:
 
 @example
 $ @kbd{gawk 'BEGIN @{ print "021 is", 021 ; print 018 @}'}
@@ -10088,19 +10316,17 @@ $ @kbd{gawk 'BEGIN @{ printf "0x11 is <%s>\n", 0x11 @}'}
 @node Regexp Constants
 @subsubsection Regular Expression Constants
 
-@c STARTOFRANGE rec
 @cindex regexp constants
 @cindex @code{~} (tilde), @code{~} operator
 @cindex tilde (@code{~}), @code{~} operator
 @cindex @code{!} (exclamation point), @code{!~} operator
 @cindex exclamation point (@code{!}), @code{!~} operator
-A regexp constant is a regular expression description enclosed in
+A @dfn{regexp constant} is a regular expression description enclosed in
 slashes, such as @code{@w{/^beginning and end$/}}.  Most regexps used in
 @command{awk} programs are constant, but the @samp{~} and @samp{!~}
 matching operators can also match computed or dynamic regexps
 (which are typically just ordinary strings or variables that contain a regexp,
-but could be a more complex expression).
-@c ENDOFRANGE cnst
+but could be more complex expressions).
 
 @node Using Constant Regexps
 @subsection Using Regular Expression Constants
@@ -10112,7 +10338,7 @@ matched.
 However, regexp constants (such as @code{/foo/}) may be used like simple expressions.
 When a
 regexp constant appears by itself, it has the same meaning as if it appeared
-in a pattern, i.e., @samp{($0 ~ /foo/)}
+in a pattern (i.e., @samp{($0 ~ /foo/)}).
 @value{DARKCORNER}
 @xref{Expression Patterns}.
 This means that the following two code segments:
@@ -10180,7 +10406,7 @@ the third argument of @code{split()} to be a regexp constant, but some
 older implementations do not.
 @value{DARKCORNER}
 Because some built-in functions accept regexp constants as arguments,
-it can be confusing when attempting to use regexp constants as arguments
+confusion can arise when attempting to use regexp constants as arguments
 to user-defined functions (@pxref{User-defined}).  For example:
 
 @example
@@ -10206,19 +10432,18 @@ function mysub(pat, repl, str, global)
 In this example, the programmer wants to pass a regexp constant to the
 user-defined function @code{mysub()}, which in turn passes it on to
 either @code{sub()} or @code{gsub()}.  However, what really happens is that
-the @code{pat} parameter is either one or zero, depending upon whether
+the @code{pat} parameter is assigned a value of either one or zero, depending upon whether
 or not @code{$0} matches @code{/hi/}.
 @command{gawk} issues a warning when it sees a regexp constant used as
-a parameter to a user-defined function, since passing a truth value in
+a parameter to a user-defined function, because passing a truth value in
 this way is probably not what was intended.
-@c ENDOFRANGE rec
 
 @node Variables
 @subsection Variables
 
 @cindex variables, user-defined
 @cindex user-defined, variables
-Variables are ways of storing values at one point in your program for
+@dfn{Variables} are ways of storing values at one point in your program for
 use later in another part of your program.  They can be manipulated
 entirely within the program text, and they can also be assigned values
 on the @command{awk} command line.
@@ -10246,18 +10471,18 @@ are distinct variables.
 A variable name is a valid expression by itself; it represents the
 variable's current value.  Variables are given new values with
 @dfn{assignment operators}, @dfn{increment operators}, and
-@dfn{decrement operators}.
-@xref{Assignment Ops}.
+@dfn{decrement operators}
+(@pxref{Assignment Ops}).
 In addition, the @code{sub()} and @code{gsub()} functions can
-change a variable's value, and the @code{match()}, @code{split()}
+change a variable's value, and the @code{match()}, @code{split()},
 and @code{patsplit()} functions can change the contents of their
-array parameters. @xref{String Functions}.
+array parameters (@pxref{String Functions}).
 
 @cindex variables, built-in
 @cindex variables, initializing
 A few variables have special built-in meanings, such as @code{FS} (the
-field separator), and @code{NF} (the number of fields in the current input
-record).  @xref{Built-in Variables}, for a list of the predefined variables.
+field separator) and @code{NF} (the number of fields in the current input
+record).  @DBXREF{Built-in Variables} for a list of the predefined variables.
 These predefined variables can be used and assigned just like all other
 variables, but their values are also used or changed automatically by
 @command{awk}.  All predefined variables' names are entirely uppercase.
@@ -10298,7 +10523,7 @@ as in the following:
 the variable is set at the very beginning, even before the
 @code{BEGIN} rules execute.  The @option{-v} option and its assignment
 must precede all the @value{FN} arguments, as well as the program text.
-(@xref{Options}, for more information about
+(@DBXREF{Options} for more information about
 the @option{-v} option.)
 Otherwise, the variable assignment is performed at a time determined by
 its position among the input file arguments---after the processing of the
@@ -10338,7 +10563,7 @@ sequences
 @node Conversion
 @subsection Conversion of Strings and Numbers
 
-Number to string and string to number conversion are generally
+Number-to-string and string-to-number conversion are generally
 straightforward.  There can be subtleties to be aware of;
 this @value{SECTION} discusses this important facet of @command{awk}.
 
@@ -10349,7 +10574,7 @@ this @value{SECTION} discusses this important facet of @command{awk}.
 @end menu
 
 @node Strings And Numbers
-@subsubsection How @command{awk} Converts Between Strings And Numbers
+@subsubsection How @command{awk} Converts Between Strings and Numbers
 
 @cindex converting, strings to numbers
 @cindex strings, converting
@@ -10380,7 +10605,7 @@ string, concatenate that number with the empty string, @code{""}.
 To force a string to be converted to a number, add zero to that string.
 A string is converted to a number by interpreting any numeric prefix
 of the string as numerals:
-@code{"2.5"} converts to 2.5, @code{"1e3"} converts to 1000, and @code{"25fix"}
+@code{"2.5"} converts to 2.5, @code{"1e3"} converts to 1,000, and @code{"25fix"}
 has a numeric value of 25.
 Strings that can't be interpreted as valid numbers convert to zero.
 
@@ -10420,7 +10645,7 @@ b = a ""
 @code{b} has the value @code{"12"}, not @code{"12.00"}.
 @value{DARKCORNER}
 
-@sidebar Pre-POSIX @command{awk} Used @code{OFMT} For String Conversion
+@sidebar Pre-POSIX @command{awk} Used @code{OFMT} for String Conversion
 @cindex POSIX @command{awk}, @code{OFMT} variable and
 @cindex @code{OFMT} variable
 @cindex portability, new @command{awk} vs.@: old @command{awk}
@@ -10432,7 +10657,7 @@ specifies the output format to use when printing numbers with @code{print}.
 conversion from the semantics of printing.  Both @code{CONVFMT} and
 @code{OFMT} have the same default value: @code{"%.6g"}.  In the vast majority
 of cases, old @command{awk} programs do not change their behavior.
-@xref{Print}, for more information on the @code{print} statement.
+@DBXREF{Print} for more information on the @code{print} statement.
 @end sidebar
 
 @node Locale influences conversions
@@ -10454,7 +10679,7 @@ The POSIX standard says that @command{awk} always uses the period as the decimal
 point when reading the @command{awk} program source code, and for
 command-line variable assignments (@pxref{Other Arguments}).  However,
 when interpreting input data, for @code{print} and @code{printf} output,
-and for number to string conversion, the local decimal point character
+and for number-to-string conversion, the local decimal point character
 is used.  @value{DARKCORNER} In all cases, numbers in source code and
 in input data cannot have a thousands separator.  Here are some examples
 indicating the difference in behavior, on a GNU/Linux system:
@@ -10479,12 +10704,12 @@ as the full number including the fractional part, 4.321.
 
 Some earlier versions of @command{gawk} fully complied with this aspect
 of the standard.  However, many users in non-English locales complained
-about this behavior, since their data used a period as the decimal
+about this behavior, because their data used a period as the decimal
 point, so the default behavior was restored to use a period as the
 decimal point character.  You can use the @option{--use-lc-numeric}
 option (@pxref{Options}) to force @command{gawk} to use the locale's
 decimal point character.  (@command{gawk} also uses the locale's decimal
-point character when in POSIX mode, either via @option{--posix}, or the
+point character when in POSIX mode, either via @option{--posix} or the
 @env{POSIXLY_CORRECT} environment variable, as shown previously.)
 
 @ref{table-locale-affects} describes the cases in which the locale's decimal
@@ -10492,7 +10717,7 @@ point character is used and when a period is used. Some of these
 features have not been described yet.
 
 @float Table,table-locale-affects
-@caption{Locale Decimal Point versus A Period}
+@caption{Locale decimal point versus a period}
 @multitable @columnfractions .15 .20 .45
 @headitem Feature @tab Default @tab @option{--posix} or @option{--use-lc-numeric}
 @item @code{%'g} @tab Use locale @tab Use locale
@@ -10502,15 +10727,15 @@ features have not been described yet.
 @end multitable
 @end float
 
-Finally, modern day formal standards and IEEE standard floating point
+Finally, modern-day formal standards and the IEEE standard floating-point
 representation can have an unusual but important effect on the way
 @command{gawk} converts some special string values to numbers.  The details
 are presented in @ref{POSIX Floating Point Problems}.
 
 @node All Operators
-@section Operators: Doing Something With Values
+@section Operators: Doing Something with Values
 
-This @value{SECTION} introduces the @dfn{operators} which make use
+This @value{SECTION} introduces the @dfn{operators} that make use
 of the values provided by constants and variables.
 
 @menu
@@ -10587,7 +10812,7 @@ Multiplication.
 Division;  because all numbers in @command{awk} are floating-point
 numbers, the result is @emph{not} rounded to an integer---@samp{3 / 4} has
 the value 0.75.  (It is a common mistake, especially for C programmers,
-to forget that @emph{all} numbers in @command{awk} are floating-point,
+to forget that @emph{all} numbers in @command{awk} are floating point,
 and that division of integer-looking constants produces a real number,
 not an integer.)
 
@@ -10672,7 +10897,7 @@ $ @kbd{awk '@{ print "Field number one:" $1 @}' mail-list}
 
 @cindex troubleshooting, string concatenation
 Because string concatenation does not have an explicit operator, it is
-often necessary to insure that it happens at the right time by using
+often necessary to ensure that it happens at the right time by using
 parentheses to enclose the items to concatenate.  For example,
 you might expect that the
 following code fragment concatenates @code{file} and @code{name}:
@@ -10688,7 +10913,7 @@ print "something meaningful" > file name
 @noindent
 This produces a syntax error with some versions of Unix
 @command{awk}.@footnote{It happens that BWK
-@command{awk}, @command{gawk} and @command{mawk} all ``get it right,''
+@command{awk}, @command{gawk}, and @command{mawk} all ``get it right,''
 but you should not rely on this.}
 It is necessary to use the following:
 
@@ -10777,11 +11002,8 @@ you're never quite sure what you'll get.
 
 @node Assignment Ops
 @subsection Assignment Expressions
-@c STARTOFRANGE asop
 @cindex assignment operators
-@c STARTOFRANGE opas
 @cindex operators, assignment
-@c STARTOFRANGE exas
 @cindex expressions, assignment
 @cindex @code{=} (equals sign), @code{=} operator
 @cindex equals sign (@code{=}), @code{=} operator
@@ -10934,7 +11156,14 @@ The indices of @code{bar} are practically guaranteed to be different, because
 @code{rand()} returns different values each time it is called.
 (Arrays and the @code{rand()} function haven't been covered yet.
 @xref{Arrays},
-and see @ref{Numeric Functions}, for more information).
+and
+@ifnotdocbook
+@DBPXREF{Numeric Functions}
+@end ifnotdocbook
+@ifdocbook
+@DBREF{Numeric Functions}
+@end ifdocbook
+for more information.)
 This example illustrates an important fact about assignment
 operators: the lefthand expression is only evaluated @emph{once}.
 
@@ -10967,7 +11196,7 @@ to a number.
 @cindex @code{*} (asterisk), @code{**=} operator
 @cindex asterisk (@code{*}), @code{**=} operator
 @float Table,table-assign-ops
-@caption{Arithmetic Assignment Operators}
+@caption{Arithmetic assignment operators}
 @multitable @columnfractions .30 .70
 @headitem Operator @tab Effect
 @item @var{lvalue} @code{+=} @var{increment} @tab Add @var{increment} to the value of @var{lvalue}.
@@ -10979,7 +11208,7 @@ to a number.
 @cindex extensions, common@comma{} @code{**=} operator
 @cindex @command{awk} language, POSIX version
 @cindex POSIX @command{awk}
-@item @var{lvalue} @code{^=} @var{power} @tab
+@item @var{lvalue} @code{^=} @var{power} @tab Raise @var{lvalue} to the power @var{power}.
 @item @var{lvalue} @code{**=} @var{power} @tab Raise @var{lvalue} to the power @var{power}. @value{COMMONEXT}
 @end multitable
 @end float
@@ -11011,7 +11240,7 @@ This is most notable in some commercial @command{awk} versions.
 For example:
 
 @example
-$ awk /==/ /dev/null
+$ @kbd{awk /==/ /dev/null}
 @error{} awk: syntax error at source line 1
 @error{}  context is
 @error{}         >>> /= <<<
@@ -11028,16 +11257,11 @@ awk '/[=]=/' /dev/null
 @command{gawk} does not have this problem; BWK @command{awk}
 and @command{mawk} also do not.
 @end sidebar
-@c ENDOFRANGE exas
-@c ENDOFRANGE opas
-@c ENDOFRANGE asop
 
 @node Increment Ops
 @subsection Increment and Decrement Operators
 
-@c STARTOFRANGE inop
 @cindex increment operators
-@c STARTOFRANGE opde
 @cindex operators, decrement/increment
 @dfn{Increment} and @dfn{decrement operators} increase or decrease the value of
 a variable by one.  An assignment operator can do the same thing, so
@@ -11061,13 +11285,14 @@ has the value four, but it changes the value of @code{foo} to five.
 In other words, the operator returns the old value of the variable,
 but with the side effect of incrementing it.
 
+@c FIXME: Use @sup here for superscript
 The post-increment @samp{foo++} is nearly the same as writing @samp{(foo
 += 1) - 1}.  It is not perfectly equivalent because all numbers in
-@command{awk} are floating-point---in floating-point, @samp{foo + 1 - 1} does
+@command{awk} are floating point---in floating point, @samp{foo + 1 - 1} does
 not necessarily equal @code{foo}.  But the difference is minute as
 long as you stick to numbers that are fairly small (less than
 @iftex
-@math{10^12}).
+@math{10^{12}}).
 @end iftex
 @ifnottex
 @ifnotdocbook
@@ -11085,7 +11310,6 @@ just like variables.  (Use @samp{$(i++)} when you want to do a field reference
 and a variable increment at the same time.  The parentheses are necessary
 because of the precedence of the field reference operator @samp{$}.)
 
-@c STARTOFRANGE deop
 @cindex decrement operators
 The decrement operator @samp{--} works just like @samp{++}, except that
 it subtracts one instead of adding it.  As with @samp{++}, it can be used before
@@ -11125,8 +11349,8 @@ like @samp{@var{lvalue}++}, but instead of adding, it subtracts.)
 @cindex evaluation order
 @cindex Marx, Groucho
 @quotation
-@i{Doctor, doctor!  It hurts when I do this!@*
-So don't do that!}
+@i{Doctor, it hurts when I do this!@*
+Then don't do that!}
 @author Groucho Marx
 @end quotation
 
@@ -11150,7 +11374,7 @@ print b
 @cindex side effects
 In other words, when do the various side effects prescribed by the
 postfix operators (@samp{b++}) take effect?
-When side effects happen is @dfn{implementation defined}.
+When side effects happen is @dfn{implementation-defined}.
 In other words, it is up to the particular version of @command{awk}.
 The result for the first example may be 12 or 13, and for the second, it
 may be 22 or 23.
@@ -11161,14 +11385,11 @@ You should avoid such things in your own programs.
 @c You'll sleep better at night and be able to look at yourself
 @c in the mirror in the morning.
 @end sidebar
-@c ENDOFRANGE inop
-@c ENDOFRANGE opde
-@c ENDOFRANGE deop
 
 @node Truth Values and Conditions
 @section Truth Values and Conditions
 
-In certain contexts, expression values also serve as ``truth values;'' i.e.,
+In certain contexts, expression values also serve as ``truth values''; i.e.,
 they determine what should happen next as the program runs. This
 @value{SECTION} describes how @command{awk} defines ``true'' and ``false''
 and how values are compared.
@@ -11225,22 +11446,21 @@ the string constant @code{"0"} is actually true, because it is non-null.
 @subsection Variable Typing and Comparison Expressions
 @quotation
 @i{The Guide is definitive. Reality is frequently inaccurate.}
-@author The Hitchhiker's Guide to the Galaxy
+@author Douglas Adams, @cite{The Hitchhiker's Guide to the Galaxy}
 @end quotation
+@c 2/2015: Antonio Colombo points out that this is really from
+@c The Restaurant at the End of the Universe. But I'm going to
+@c leave it alone.
 
-@c STARTOFRANGE comex
 @cindex comparison expressions
-@c STARTOFRANGE excom
 @cindex expressions, comparison
 @cindex expressions, matching, See comparison expressions
 @cindex matching, expressions, See comparison expressions
 @cindex relational operators, See comparison operators
 @cindex operators, relational, See operators@comma{} comparison
-@c STARTOFRANGE varting
 @cindex variable typing
-@c STARTOFRANGE vartypc
 @cindex variables, types of, comparison expressions and
-Unlike other programming languages, @command{awk} variables do not have a
+Unlike in other programming languages, in @command{awk} variables do not have a
 fixed type. Instead, they can be either a number or a string, depending
 upon the value that is assigned to them.
 We look now at how variables are typed, and how @command{awk}
@@ -11253,7 +11473,7 @@ compares variables.
 @end menu
 
 @node Variable Typing
-@subsubsection String Type Versus Numeric Type
+@subsubsection String Type versus Numeric Type
 
 @cindex numeric, strings
 @cindex strings, numeric
@@ -11269,20 +11489,20 @@ Variable typing follows these rules:
 
 @itemize @value{BULLET}
 @item
-A numeric constant or the result of a numeric operation has the @var{numeric}
+A numeric constant or the result of a numeric operation has the @dfn{numeric}
 attribute.
 
 @item
-A string constant or the result of a string operation has the @var{string}
+A string constant or the result of a string operation has the @dfn{string}
 attribute.
 
 @item
 Fields, @code{getline} input, @code{FILENAME}, @code{ARGV} elements,
 @code{ENVIRON} elements, and the elements of an array created by
-@code{match()}, @code{split()} and @code{patsplit()} that are numeric
-strings have the @var{strnum} attribute.  Otherwise, they have
-the @var{string} attribute.  Uninitialized variables also have the
-@var{strnum} attribute.
+@code{match()}, @code{split()}, and @code{patsplit()} that are numeric
+strings have the @dfn{strnum} attribute.  Otherwise, they have
+the @dfn{string} attribute.  Uninitialized variables also have the
+@dfn{strnum} attribute.
 
 @item
 Attributes propagate across assignments but are not changed by
@@ -11426,13 +11646,13 @@ constant, then a string comparison is performed.  Otherwise, a
 numeric comparison is performed.
 
 This point bears additional emphasis: All user input is made of characters,
-and so is first and foremost of @var{string} type; input strings
-that look numeric are additionally given the @var{strnum} attribute.
+and so is first and foremost of string type; input strings
+that look numeric are additionally given the strnum attribute.
 Thus, the six-character input string @w{@samp{ +3.14}} receives the
-@var{strnum} attribute. In contrast, the eight characters
+strnum attribute. In contrast, the eight characters
 @w{@code{" +3.14"}} appearing in program text comprise a string constant.
 The following examples print @samp{1} when the comparison between
-the two different constants is true, @samp{0} otherwise:
+the two different constants is true, and @samp{0} otherwise:
 
 @c 22.9.2014: Tested with mawk and BWK awk, got same results.
 @example
@@ -11480,18 +11700,18 @@ operators}, which are a superset of those in C.
 @cindex exclamation point (@code{!}), @code{!~} operator
 @cindex @code{in} operator
 @float Table,table-relational-ops
-@caption{Relational Operators}
+@caption{Relational operators}
 @multitable @columnfractions .25 .75
 @headitem Expression @tab Result
-@item @var{x} @code{<} @var{y} @tab True if @var{x} is less than @var{y}.
-@item @var{x} @code{<=} @var{y} @tab True if @var{x} is less than or equal to @var{y}.
-@item @var{x} @code{>} @var{y} @tab True if @var{x} is greater than @var{y}.
-@item @var{x} @code{>=} @var{y} @tab True if @var{x} is greater than or equal to @var{y}.
-@item @var{x} @code{==} @var{y} @tab True if @var{x} is equal to @var{y}.
-@item @var{x} @code{!=} @var{y} @tab True if @var{x} is not equal to @var{y}.
-@item @var{x} @code{~} @var{y} @tab True if the string @var{x} matches the regexp denoted by @var{y}.
-@item @var{x} @code{!~} @var{y} @tab True if the string @var{x} does not match the regexp denoted by @var{y}.
-@item @var{subscript} @code{in} @var{array} @tab True if the array @var{array} has an element with the subscript @var{subscript}.
+@item @var{x} @code{<} @var{y} @tab True if @var{x} is less than @var{y}
+@item @var{x} @code{<=} @var{y} @tab True if @var{x} is less than or equal to @var{y}
+@item @var{x} @code{>} @var{y} @tab True if @var{x} is greater than @var{y}
+@item @var{x} @code{>=} @var{y} @tab True if @var{x} is greater than or equal to @var{y}
+@item @var{x} @code{==} @var{y} @tab True if @var{x} is equal to @var{y}
+@item @var{x} @code{!=} @var{y} @tab True if @var{x} is not equal to @var{y}
+@item @var{x} @code{~} @var{y} @tab True if the string @var{x} matches the regexp denoted by @var{y}
+@item @var{x} @code{!~} @var{y} @tab True if the string @var{x} does not match the regexp denoted by @var{y}
+@item @var{subscript} @code{in} @var{array} @tab True if the array @var{array} has an element with the subscript @var{subscript}
 @end multitable
 @end float
 
@@ -11529,24 +11749,24 @@ The following list of expressions illustrates the kinds of comparisons
 
 @table @code
 @item 1.5 <= 2.0
-numeric comparison (true)
+Numeric comparison (true)
 
 @item "abc" >= "xyz"
-string comparison (false)
+String comparison (false)
 
 @item 1.5 != " +2"
-string comparison (true)
+String comparison (true)
 
 @item "1e2" < "3"
-string comparison (true)
+String comparison (true)
 
 @item a = 2; b = "2"
 @itemx a == b
-string comparison (true)
+String comparison (true)
 
 @item a = 2; b = " +2"
 @itemx a == b
-string comparison (false)
+String comparison (false)
 @end table
 
 In this example:
@@ -11562,7 +11782,7 @@ $ @kbd{echo 1e2 3 | awk '@{ print ($1 < $2) ? "true" : "false" @}'}
 @noindent
 the result is @samp{false} because both @code{$1} and @code{$2}
 are user input.  They are numeric strings---therefore both have
-the @var{strnum} attribute, dictating a numeric comparison.
+the strnum attribute, dictating a numeric comparison.
 The purpose of the comparison rules and the use of numeric strings is
 to attempt to produce the behavior that is ``least surprising,'' while
 still ``doing the right thing.''
@@ -11599,7 +11819,7 @@ dynamic regexp (@pxref{Regexp Usage}; also
 @cindex @command{awk}, regexp constants and
 @cindex regexp constants
 A constant regular
-expression in slashes by itself is also an expression.  The regexp
+expression in slashes by itself is also an expression.
 @code{/@var{regexp}/} is an abbreviation for the following comparison expression:
 
 @example
@@ -11613,7 +11833,7 @@ One special place where @code{/foo/} is @emph{not} an abbreviation for
 where this is discussed in more detail.
 
 @node POSIX String Comparison
-@subsubsection String Comparison With POSIX Rules
+@subsubsection String Comparison with POSIX Rules
 
 The POSIX standard says that string comparison is performed based
 on the locale's @dfn{collating order}. This is the order in which
@@ -11621,7 +11841,7 @@ characters sort, as defined by the locale (for more discussion,
 @pxref{Locales}).  This order is usually very different
 from the results obtained when doing straight character-by-character
 comparison.@footnote{Technically, string comparison is supposed
-to behave the same way as if the strings are compared with the C
+to behave the same way as if the strings were compared with the C
 @code{strcoll()} function.}
 
 Because this behavior differs considerably from existing practice,
@@ -11638,19 +11858,13 @@ $ @kbd{gawk --posix 'BEGIN @{ printf("ABC < abc = %s\n",}
 @print{} ABC < abc = FALSE
 @end example
 
-@c ENDOFRANGE comex
-@c ENDOFRANGE excom
-@c ENDOFRANGE vartypc
-@c ENDOFRANGE varting
 
 @node Boolean Ops
 @subsection Boolean Expressions
 @cindex and Boolean-logic operator
 @cindex or Boolean-logic operator
 @cindex not Boolean-logic operator
-@c STARTOFRANGE exbo
 @cindex expressions, Boolean
-@c STARTOFRANGE boex
 @cindex Boolean expressions
 @cindex operators, Boolean, See Boolean expressions
 @cindex Boolean operators, See Boolean expressions
@@ -11734,7 +11948,7 @@ BEGIN @{ if (! ("HOME" in ENVIRON))
 @cindex vertical bar (@code{|}), @code{||} operator
 The @samp{&&} and @samp{||} operators are called @dfn{short-circuit}
 operators because of the way they work.  Evaluation of the full expression
-is ``short-circuited'' if the result can be determined part way through
+is ``short-circuited'' if the result can be determined partway through
 its evaluation.
 
 @cindex line continuations
@@ -11796,8 +12010,6 @@ next record, and start processing the rules over again at the top.
 The reason it's there is to avoid printing the bracketing
 @samp{START} and @samp{END} lines.
 @end quotation
-@c ENDOFRANGE exbo
-@c ENDOFRANGE boex
 
 @node Conditional Exp
 @subsection Conditional Expressions
@@ -11808,8 +12020,8 @@ The reason it's there is to avoid printing the bracketing
 A @dfn{conditional expression} is a special kind of expression that has
 three operands.  It allows you to use one expression's value to select
 one of two other expressions.
-The conditional expression is the same as in the C language,
-as shown here:
+The conditional expression in @command{awk} is the same as in the C
+language, as shown here:
 
 @example
 @var{selector} ? @var{if-true-exp} : @var{if-false-exp}
@@ -11818,8 +12030,8 @@ as shown here:
 @noindent
 There are three subexpressions.  The first, @var{selector}, is always
 computed first.  If it is ``true'' (not zero or not null), then
-@var{if-true-exp} is computed next and its value becomes the value of
-the whole expression.  Otherwise, @var{if-false-exp} is computed next
+@var{if-true-exp} is computed next, and its value becomes the value of
+the whole expression.  Otherwise, @var{if-false-exp} is computed next,
 and its value becomes the value of the whole expression.
 For example, the following expression produces the absolute value of @code{x}:
 
@@ -11867,15 +12079,15 @@ ask for it by name at any point in the program.  For
 example, the function @code{sqrt()} computes the square root of a number.
 
 @cindex functions, built-in
-A fixed set of functions are @dfn{built-in}, which means they are
+A fixed set of functions are @dfn{built in}, which means they are
 available in every @command{awk} program.  The @code{sqrt()} function is one
-of these.  @xref{Built-in}, for a list of built-in
+of these.  @DBXREF{Built-in} for a list of built-in
 functions and their descriptions.  In addition, you can define
 functions for use in your program.
-@xref{User-defined},
+@DBXREF{User-defined}
 for instructions on how to do this.
 Finally, @command{gawk} lets you write functions in C or C++
-that may be called from your program: see @ref{Dynamic Extensions}.
+that may be called from your program (@pxref{Dynamic Extensions}).
 
 @cindex arguments, in function calls
 The way to use a function is with a @dfn{function call} expression,
@@ -11894,7 +12106,7 @@ rand()                 @ii{no arguments}
 
 @cindex troubleshooting, function call syntax
 @quotation CAUTION
-Do not put any space between the function name and the open-parenthesis!
+Do not put any space between the function name and the opening parenthesis!
 A user-defined function name looks just like the name of a
 variable---a space would make the expression look like concatenation of
 a variable with an expression inside parentheses.
@@ -11915,7 +12127,7 @@ Some of the built-in functions have one or
 more optional arguments.
 If those arguments are not supplied, the functions
 use a reasonable default value.
-@xref{Built-in}, for full details.  If arguments
+@DBXREF{Built-in} for full details.  If arguments
 are omitted in calls to user-defined functions, then those arguments are
 treated as local variables. Such local variables act like the
 empty string if referenced where a string value is required,
@@ -11976,9 +12188,7 @@ $ @kbd{awk -f matchit.awk}
 
 @node Precedence
 @section Operator Precedence (How Operators Nest)
-@c STARTOFRANGE prec
 @cindex precedence
-@c STARTOFRANGE oppr
 @cindex operators, precedence
 
 @dfn{Operator precedence} determines how operators are grouped when
@@ -12043,7 +12253,7 @@ Increment, decrement.
 @cindex @code{*} (asterisk), @code{**} operator
 @cindex asterisk (@code{*}), @code{**} operator
 @item @code{^ **}
-Exponentiation.  These operators group right-to-left.
+Exponentiation.  These operators group right to left.
 
 @cindex @code{+} (plus sign), @code{+} operator
 @cindex plus sign (@code{+}), @code{+} operator
@@ -12070,7 +12280,7 @@ Multiplication, division, remainder.
 @item @code{+ -}
 Addition, subtraction.
 
-@item String Concatenation
+@item String concatenation
 There is no special symbol for concatenation.
 The operands are simply written side by side
 (@pxref{Concatenation}).
@@ -12109,7 +12319,7 @@ statements belong to the statement level, not to expressions.  The
 redirection does not produce an expression that could be the operand of
 another operator.  As a result, it does not make sense to use a
 redirection operator near another operator of lower precedence without
-parentheses.  Such combinations (for example, @samp{print foo > a ? b : c}),
+parentheses.  Such combinations (e.g., @samp{print foo > a ? b : c})
 result in syntax errors.
 The correct way to write this statement is @samp{print foo > (a ? b : c)}.
 
@@ -12127,17 +12337,17 @@ Array membership.
 @cindex @code{&} (ampersand), @code{&&} operator
 @cindex ampersand (@code{&}), @code{&&} operator
 @item @code{&&}
-Logical ``and''.
+Logical ``and.''
 
 @cindex @code{|} (vertical bar), @code{||} operator
 @cindex vertical bar (@code{|}), @code{||} operator
 @item @code{||}
-Logical ``or''.
+Logical ``or.''
 
 @cindex @code{?} (question mark), @code{?:} operator
 @cindex question mark (@code{?}), @code{?:} operator
 @item @code{?:}
-Conditional.  This operator groups right-to-left.
+Conditional.  This operator groups right to left.
 
 @cindex @code{+} (plus sign), @code{+=} operator
 @cindex plus sign (@code{+}), @code{+=} operator
@@ -12154,7 +12364,7 @@ Conditional.  This operator groups right-to-left.
 @cindex @code{^} (caret), @code{^=} operator
 @cindex caret (@code{^}), @code{^=} operator
 @item @code{= += -= *= /= %= ^= **=}
-Assignment.  These operators group right-to-left.
+Assignment.  These operators group right to left.
 @end table
 
 @cindex POSIX @command{awk}, @code{**} operator and
@@ -12163,11 +12373,9 @@ Assignment.  These operators group right-to-left.
 The @samp{|&}, @samp{**}, and @samp{**=} operators are not specified by POSIX.
 For maximum portability, do not use them.
 @end quotation
-@c ENDOFRANGE prec
-@c ENDOFRANGE oppr
 
 @node Locales
-@section Where You Are Makes A Difference
+@section Where You Are Makes a Difference
 @cindex locale, definition of
 
 Modern systems support the notion of @dfn{locales}: a way to tell the
@@ -12187,8 +12395,8 @@ character}, to find the record terminator.
 
 Locales can affect how dates and times are formatted (@pxref{Time
 Functions}).  For example, a common way to abbreviate the date September
-4, 2015 in the United States is ``9/4/15.''  In many countries in
-Europe, however, it is abbreviated ``4.9.15.''  Thus, the @code{%x}
+4, 2015, in the United States is ``9/4/15.''  In many countries in
+Europe, however, it is abbreviated ``4.9.15.''  Thus, the @samp{%x}
 specification in a @code{"US"} locale might produce @samp{9/4/15},
 while in a @code{"EUROPE"} locale, it might produce @samp{4.9.15}.
 
@@ -12206,13 +12414,13 @@ in @ref{Conversion}.
 @itemize @value{BULLET}
 @item
 Expressions are the basic elements of computation in programs.  They are
-built from constants, variables, function calls and combinations of the
+built from constants, variables, function calls, and combinations of the
 various kinds of values with operators.
 
 @item
 @command{awk} supplies three kinds of constants: numeric, string, and
 regexp.  @command{gawk} lets you specify numeric constants in octal
-and hexadecimal (bases 8 and 16) in addition to decimal (base 10).
+and hexadecimal (bases 8 and 16) as well as decimal (base 10).
 In certain contexts, a standalone regexp constant such as @code{/foo/}
 has the same meaning as @samp{$0 ~ /foo/}.
 
@@ -12230,8 +12438,8 @@ Locales can influence the conversions.
 @item
 @command{awk} provides the usual arithmetic operators (addition,
 subtraction, multiplication, division, modulus), and unary plus and minus.
-It also provides comparison operators, boolean operators, array membership
-testing, and regexp
+It also provides comparison operators, Boolean operators, an array membership
+testing operator, and regexp
 matching operators.  String concatenation is accomplished by placing
 two expressions next to each other; there is no explicit operator.
 The three-operand @samp{?:} operator provides an ``if-else'' test within
@@ -12242,7 +12450,7 @@ Assignment operators provide convenient shorthands for common arithmetic
 operations.
 
 @item
-In @command{awk}, a value is considered to be true if it is non-zero
+In @command{awk}, a value is considered to be true if it is nonzero
 @emph{or} non-null. Otherwise, the value is false.
 
 @item
@@ -12251,11 +12459,11 @@ lifetime.  The type determines how it behaves in comparisons (string
 or numeric).
 
 @item
-Function calls return a value which may be used as part of a larger
+Function calls return a value that may be used as part of a larger
 expression.  Expressions used to pass parameter values are fully
 evaluated before the function is called.  @command{awk} provides
-built-in and user-defined functions; this is described later on in this
-@value{DOCUMENT}.
+built-in and user-defined functions; this is described in
+@ref{Functions}.
 
 @item
 Operator precedence specifies the order in which operations are performed,
@@ -12268,11 +12476,9 @@ program, and occasionally the format for data read as input.
 
 @end itemize
 
-@c ENDOFRANGE exps
 
 @node Patterns and Actions
 @chapter Patterns, Actions, and Variables
-@c STARTOFRANGE pat
 @cindex patterns
 
 As you have already seen, each @command{awk} statement consists of
@@ -12280,7 +12486,7 @@ a pattern with an associated action.  This @value{CHAPTER} describes how
 you build patterns and actions, what kinds of things you can do within
 actions, and @command{awk}'s predefined variables.
 
-The pattern-action rules and the statements available for use
+The pattern--action rules and the statements available for use
 within actions form the core of @command{awk} programming.
 In a sense, everything covered
 up to here has been the foundation
@@ -12416,8 +12622,8 @@ $ @kbd{awk '$1 ~ /li/ @{ print $2 @}' mail-list}
 @cindex regexp constants, as patterns
 @cindex patterns, regexp constants as
 A regexp constant as a pattern is also a special case of an expression
-pattern.  The expression @samp{/li/} has the value one if @samp{li}
-appears in the current input record. Thus, as a pattern, @samp{/li/}
+pattern.  The expression @code{/li/} has the value one if @samp{li}
+appears in the current input record. Thus, as a pattern, @code{/li/}
 matches any record containing @samp{li}.
 
 @cindex Boolean expressions, as patterns
@@ -12468,11 +12674,11 @@ The subexpressions of a Boolean operator in a pattern can be constant regular
 expressions, comparisons, or any other @command{awk} expressions.  Range
 patterns are not expressions, so they cannot appear inside Boolean
 patterns.  Likewise, the special patterns @code{BEGIN}, @code{END},
-@code{BEGINFILE} and @code{ENDFILE},
+@code{BEGINFILE}, and @code{ENDFILE},
 which never match any input record, are not expressions and cannot
 appear inside Boolean patterns.
 
-The precedence of the different operators which can appear in
+The precedence of the different operators that can appear in
 patterns is described in @ref{Precedence}.
 
 @node Ranges
@@ -12498,7 +12704,7 @@ prints every record in @file{myfile} between @samp{on}/@samp{off} pairs, inclusi
 
 A range pattern starts out by matching @var{begpat} against every
 input record.  When a record matches @var{begpat}, the range pattern is
-@dfn{turned on} and the range pattern matches this record as well.  As long as
+@dfn{turned on}, and the range pattern matches this record as well.  As long as
 the range pattern stays turned on, it automatically matches every input
 record read.  The range pattern also matches @var{endpat} against every
 input record; when this succeeds, the range pattern is @dfn{turned off} again
@@ -12569,9 +12775,7 @@ a range pattern.  @value{DARKCORNER}
 @node BEGIN/END
 @subsection The @code{BEGIN} and @code{END} Special Patterns
 
-@c STARTOFRANGE beg
 @cindex @code{BEGIN} pattern
-@c STARTOFRANGE end
 @cindex @code{END} pattern
 All the patterns described so far are for matching input records.
 The @code{BEGIN} and @code{END} special patterns are different.
@@ -12579,7 +12783,7 @@ They supply startup and cleanup actions for @command{awk} programs.
 @code{BEGIN} and @code{END} rules must have actions; there is no default
 action for these rules because there is no current record when they run.
 @code{BEGIN} and @code{END} rules are often referred to as
-``@code{BEGIN} and @code{END} blocks'' by long-time @command{awk}
+``@code{BEGIN} and @code{END} blocks'' by longtime @command{awk}
 programmers.
 
 @menu
@@ -12610,7 +12814,7 @@ $ @kbd{awk '}
 This program finds the number of records in the input file @file{mail-list}
 that contain the string @samp{li}.  The @code{BEGIN} rule prints a title
 for the report.  There is no need to use the @code{BEGIN} rule to
-initialize the counter @code{n} to zero, since @command{awk} does this
+initialize the counter @code{n} to zero, as @command{awk} does this
 automatically (@pxref{Variables}).
 The second rule increments the variable @code{n} every time a
 record containing the pattern @samp{li} is read.  The @code{END} rule
@@ -12638,13 +12842,13 @@ The order in which library functions are named on the command line
 controls the order in which their @code{BEGIN} and @code{END} rules are
 executed.  Therefore, you have to be careful when writing such rules in
 library files so that the order in which they are executed doesn't matter.
-@xref{Options}, for more information on
+@DBXREF{Options} for more information on
 using library functions.
 @xref{Library Functions},
 for a number of useful library functions.
 
 If an @command{awk} program has only @code{BEGIN} rules and no
-other rules, then the program exits after the @code{BEGIN} rule is
+other rules, then the program exits after the @code{BEGIN} rules are
 run.@footnote{The original version of @command{awk} kept
 reading and ignoring input until the end of the file was seen.}  However, if an
 @code{END} rule exists, then the input is read, even if there are
@@ -12672,7 +12876,7 @@ Another way is simply to assign a value to @code{$0}.
 @cindex @code{print} statement, @code{BEGIN}/@code{END} patterns and
 @cindex @code{BEGIN} pattern, @code{print} statement and
 @cindex @code{END} pattern, @code{print} statement and
-The second point is similar to the first but from the other direction.
+The second point is similar to the first, but from the other direction.
 Traditionally, due largely to implementation issues, @code{$0} and
 @code{NF} were @emph{undefined} inside an @code{END} rule.
 The POSIX standard specifies that @code{NF} is available in an @code{END}
@@ -12687,11 +12891,11 @@ of Unix @command{awk} do not.
 The third point follows from the first two.  The meaning of @samp{print}
 inside a @code{BEGIN} or @code{END} rule is the same as always:
 @samp{print $0}.  If @code{$0} is the null string, then this prints an
-empty record.  Many long time @command{awk} programmers use an unadorned
+empty record.  Many longtime @command{awk} programmers use an unadorned
 @samp{print} in @code{BEGIN} and @code{END} rules, to mean @samp{@w{print ""}},
 relying on @code{$0} being null.  Although one might generally get away with
 this in @code{BEGIN} rules, it is a very bad idea in @code{END} rules,
-at least in @command{gawk}.  It is also poor style, since if an empty
+at least in @command{gawk}.  It is also poor style, because if an empty
 line is needed in the output, the program should print one explicitly.
 
 @cindex @code{next} statement, @code{BEGIN}/@code{END} patterns and
@@ -12701,11 +12905,14 @@ line is needed in the output, the program should print one explicitly.
 Finally, the @code{next} and @code{nextfile} statements are not allowed
 in a @code{BEGIN} rule, because the implicit
 read-a-record-and-match-against-the-rules loop has not started yet.  Similarly, those statements
-are not valid in an @code{END} rule, since all the input has been read.
-(@xref{Next Statement}, and see
-@ref{Nextfile Statement}.)
-@c ENDOFRANGE beg
-@c ENDOFRANGE end
+are not valid in an @code{END} rule, because all the input has been read.
+(@DBXREF{Next Statement} and
+@ifnotdocbook
+@DBPXREF{Nextfile Statement}.)
+@end ifnotdocbook
+@ifdocbook
+@DBREF{Nextfile Statement}.)
+@end ifdocbook
 
 @node BEGINFILE/ENDFILE
 @subsection The @code{BEGINFILE} and @code{ENDFILE} Special Patterns
@@ -12758,7 +12965,7 @@ fatal error.
 
 @item
 If you have written extensions that modify the record handling (by
-inserting an ``input parser,'' @pxref{Input Parsers}), you can invoke
+inserting an ``input parser''; @pxref{Input Parsers}), you can invoke
 them at this point, before @command{gawk} has started processing the file.
 (This is a @emph{very} advanced feature, currently used only by the
 @uref{http://gawkextlib.sourceforge.net, @code{gawkextlib} project}.)
@@ -12769,8 +12976,8 @@ the last record in an input file.  For the last input file,
 it will be called before any @code{END} rules.
 The @code{ENDFILE} rule is executed even for empty input files.
 
-Normally, when an error occurs when reading input in the normal input
-processing loop, the error is fatal.  However, if an @code{ENDFILE}
+Normally, when an error occurs when reading input in the normal
+input-processing loop, the error is fatal.  However, if an @code{ENDFILE}
 rule is present, the error becomes non-fatal, and instead @code{ERRNO}
 is set.  This makes it possible to catch and process I/O errors at the
 level of the @command{awk} program.
@@ -12779,7 +12986,7 @@ level of the @command{awk} program.
 The @code{next} statement (@pxref{Next Statement}) is not allowed inside
 either a @code{BEGINFILE} or an @code{ENDFILE} rule.  The @code{nextfile}
 statement is allowed only inside a
-@code{BEGINFILE} rule, but not inside an @code{ENDFILE} rule.
+@code{BEGINFILE} rule, not inside an @code{ENDFILE} rule.
 
 @cindex @code{getline} statement, @code{BEGINFILE}/@code{ENDFILE} patterns and
 The @code{getline} statement (@pxref{Getline}) is restricted inside
@@ -12826,7 +13033,6 @@ awk '@{ print $1 @}' mail-list
 
 @noindent
 prints the first field of every record.
-@c ENDOFRANGE pat
 
 @node Using Shell Variables
 @section Using Shell Variables in Programs
@@ -12860,7 +13066,7 @@ The first part is double-quoted, which allows substitution of
 the @code{pattern} shell variable inside the quotes.
 The second part is single-quoted.
 
-Variable substitution via quoting works, but can be potentially
+Variable substitution via quoting works, but can potentially be
 messy.  It requires a good understanding of the shell's quoting rules
 (@pxref{Quoting}),
 and it's often difficult to correctly
@@ -12887,7 +13093,7 @@ The assignment @samp{-v pat="$pattern"} still requires double quotes,
 in case there is whitespace in the value of @code{$pattern}.
 The @command{awk} variable @code{pat} could be named @code{pattern}
 too, but that would be more confusing.  Using a variable also
-provides more flexibility, since the variable can be used anywhere inside
+provides more flexibility, as the variable can be used anywhere inside
 the program---for printing, as an array subscript, or for any other
 use---without requiring the quoting tricks at every point in the program.
 
@@ -12960,7 +13166,7 @@ is used in order to put several statements together in the body of an
 Use the @code{getline} command
 (@pxref{Getline}).
 Also supplied in @command{awk} are the @code{next}
-statement (@pxref{Next Statement}),
+statement (@pxref{Next Statement})
 and the @code{nextfile} statement
 (@pxref{Nextfile Statement}).
 
@@ -12975,11 +13181,8 @@ For deleting array elements.
 
 @node Statements
 @section Control Statements in Actions
-@c STARTOFRANGE csta
 @cindex control statements
-@c STARTOFRANGE acs
 @cindex statements, control, in actions
-@c STARTOFRANGE accs
 @cindex actions, control statements in
 
 @dfn{Control statements}, such as @code{if}, @code{while}, and so on,
@@ -13048,7 +13251,7 @@ else
     print "x is odd"
 @end example
 
-In this example, if the expression @samp{x % 2 == 0} is true (that is,
+In this example, if the expression @samp{x % 2 == 0} is true (i.e.,
 if the value of @code{x} is evenly divisible by two), then the first
 @code{print} statement is executed; otherwise, the second @code{print}
 statement is executed.
@@ -13122,13 +13325,13 @@ The body of this loop is a compound statement enclosed in braces,
 containing two statements.
 The loop works in the following manner: first, the value of @code{i} is set to one.
 Then, the @code{while} statement tests whether @code{i} is less than or equal to
-three.  This is true when @code{i} equals one, so the @code{i}-th
+three.  This is true when @code{i} equals one, so the @code{i}th
 field is printed.  Then the @samp{i++} increments the value of @code{i}
 and the loop repeats.  The loop terminates when @code{i} reaches four.
 
 A newline is not required between the condition and the
-body; however using one makes the program clearer unless the body is a
-compound statement or else is very simple.  The newline after the open-brace
+body; however, using one makes the program clearer unless the body is a
+compound statement or else is very simple.  The newline after the open brace
 that begins the compound statement is not required either, but the
 program is harder to read without it.
 
@@ -13158,9 +13361,9 @@ while (@var{condition})
 @end example
 
 @noindent
-This statement does not execute @var{body} even once if the @var{condition}
-is false to begin with.
-The following is an example of a @code{do} statement:
+This statement does not execute the @var{body} even once if the
+@var{condition} is false to begin with.  The following is an example of
+a @code{do} statement:
 
 @example
 @{
@@ -13174,7 +13377,7 @@ The following is an example of a @code{do} statement:
 
 @noindent
 This program prints each input record 10 times.  However, it isn't a very
-realistic example, since in this case an ordinary @code{while} would do
+realistic example, because in this case an ordinary @code{while} would do
 just as well.  This situation reflects actual experience; only
 occasionally is there a real use for a @code{do} statement.
 
@@ -13227,7 +13430,7 @@ their assignments as separate statements preceding the @code{for} loop.)
 The same is true of the @var{increment} part. Incrementing additional
 variables requires separate statements at the end of the loop.
 The C compound expression, using C's comma operator, is useful in
-this context but it is not supported in @command{awk}.
+this context, but it is not supported in @command{awk}.
 
 Most often, @var{increment} is an increment expression, as in the previous
 example.  But this is not required; it can be any expression
@@ -13271,7 +13474,7 @@ very common in loops.  It can be easier to think of this counting as part
 of looping rather than as something to do inside the loop.
 
 @cindex @code{in} operator
-There is an alternate version of the @code{for} loop, for iterating over
+There is an alternative version of the @code{for} loop, for iterating over
 all the indices of an array:
 
 @example
@@ -13280,7 +13483,7 @@ for (i in array)
 @end example
 
 @noindent
-@xref{Scanning an Array},
+@DBXREF{Scanning an Array}
 for more information on this version of the @code{for} loop.
 
 @node Switch Statement
@@ -13300,7 +13503,7 @@ are checked for a match in the order they are defined.  If no suitable
 
 Each @code{case} contains a single constant, be it numeric, string, or
 regexp.  The @code{switch} expression is evaluated, and then each
-@code{case}'s constant is compared against the result in turn. The type of constant 
+@code{case}'s constant is compared against the result in turn. The type of constant
 determines the comparison: numeric or string do the usual comparisons.
 A regexp constant does a regular expression match against the string
 value of the original expression.  The general form of the @code{switch}
@@ -13318,7 +13521,7 @@ default:
 Control flow in
 the @code{switch} statement works as it does in C. Once a match to a given
 case is made, the case statement bodies execute until a @code{break},
-@code{continue}, @code{next}, @code{nextfile}  or @code{exit} is encountered,
+@code{continue}, @code{next}, @code{nextfile}, or @code{exit} is encountered,
 or the end of the @code{switch} statement itself. For example:
 
 @example
@@ -13347,9 +13550,9 @@ while ((c = getopt(ARGC, ARGV, "aksx")) != -1) @{
 @}
 @end example
 
-Note that if none of the statements specified above halt execution
+Note that if none of the statements specified here halt execution
 of a matched @code{case} statement, execution falls through to the
-next @code{case} until execution halts. In the above example, the
+next @code{case} until execution halts. In this example, the
 @code{case} for @code{"?"} falls through to the @code{default}
 case, which is to call a function named @code{usage()}.
 (The @code{getopt()} function being called here is
@@ -13370,12 +13573,12 @@ numbers:
 # find smallest divisor of num
 @{
     num = $1
-    for (div = 2; div * div <= num; div++) @{
-        if (num % div == 0)
+    for (divisor = 2; divisor * divisor <= num; divisor++) @{
+        if (num % divisor == 0)
             break
     @}
-    if (num % div == 0)
-        printf "Smallest divisor of %d is %d\n", num, div
+    if (num % divisor == 0)
+        printf "Smallest divisor of %d is %d\n", num, divisor
     else
         printf "%d is prime\n", num
 @}
@@ -13396,12 +13599,12 @@ an @code{if}:
 # find smallest divisor of num
 @{
     num = $1
-    for (div = 2; ; div++) @{
-        if (num % div == 0) @{
-            printf "Smallest divisor of %d is %d\n", num, div
+    for (divisor = 2; ; divisor++) @{
+        if (num % divisor == 0) @{
+            printf "Smallest divisor of %d is %d\n", num, divisor
             break
         @}
-        if (div * div > num) @{
+        if (divisor * divisor > num) @{
             printf "%d is prime\n", num
             break
         @}
@@ -13476,7 +13679,7 @@ BEGIN @{
 @end example
 
 @noindent
-This program loops forever once @code{x} reaches 5, since
+This program loops forever once @code{x} reaches 5, because
 the increment (@samp{x++}) is never reached.
 
 @c @cindex @code{continue}, outside of loops
@@ -13492,7 +13695,12 @@ body of a loop.  Historical versions of @command{awk} treated a @code{continue}
 statement outside a loop the same way they treated a @code{break}
 statement outside a loop: as if it were a @code{next}
 statement
+@ifset FOR_PRINT
+(discussed in the following section).
+@end ifset
+@ifclear FOR_PRINT
 (@pxref{Next Statement}).
+@end ifclear
 @value{DARKCORNER}
 Recent versions of BWK @command{awk} no longer work this way, nor
 does @command{gawk}.
@@ -13537,7 +13745,7 @@ Because of the @code{next} statement,
 the program's subsequent rules won't see the bad record.  The error
 message is redirected to the standard error output stream, as error
 messages should be.
-For more detail see
+For more detail, see
 @ref{Special Files}.
 
 If the @code{next} statement causes the end of the input to be reached,
@@ -13603,7 +13811,7 @@ rule to skip over a file that would otherwise cause @command{gawk}
 to exit with a fatal error. In this case, @code{ENDFILE} rules are not
 executed. @xref{BEGINFILE/ENDFILE}.
 
-While one might think that @samp{close(FILENAME)} would accomplish
+Although it might seem that @samp{close(FILENAME)} would accomplish
 the same as @code{nextfile}, this isn't true.  @code{close()} is
 reserved for closing files, pipes, and coprocesses that are
 opened with redirections.  It is not related to the main processing that
@@ -13611,7 +13819,7 @@ opened with redirections.  It is not related to the main processing that
 
 @quotation NOTE
 For many years, @code{nextfile} was a
-common extension. In September, 2012, it was accepted for
+common extension. In September 2012, it was accepted for
 inclusion into the POSIX standard.
 See @uref{http://austingroupbugs.net/view.php?id=607, the Austin Group website}.
 @end quotation
@@ -13620,7 +13828,7 @@ See @uref{http://austingroupbugs.net/view.php?id=607, the Austin Group website}.
 @cindex @code{nextfile} statement, user-defined functions and
 @cindex Brian Kernighan's @command{awk}
 @cindex @command{mawk} utility
-The current version of BWK @command{awk}, and @command{mawk}
+The current version of BWK @command{awk} and @command{mawk}
 also support @code{nextfile}.  However, they don't allow the
 @code{nextfile} statement inside function bodies (@pxref{User-defined}).
 @command{gawk} does; a @code{nextfile} inside a function body reads the
@@ -13658,9 +13866,9 @@ any @code{ENDFILE} rules; they do not execute.
 
 In such a case,
 if you don't want the @code{END} rule to do its job, set a variable
-to nonzero before the @code{exit} statement and check that variable in
+to a nonzero value before the @code{exit} statement and check that variable in
 the @code{END} rule.
-@xref{Assert Function},
+@DBXREF{Assert Function}
 for an example that does this.
 
 @cindex dark corner, @code{exit} statement
@@ -13671,7 +13879,7 @@ In the case where an argument
 is supplied to a first @code{exit} statement, and then @code{exit} is
 called a second time from an @code{END} rule with no argument,
 @command{awk} uses the previously supplied exit value.  @value{DARKCORNER}
-@xref{Exit Status}, for more information.
+@DBXREF{Exit Status} for more information.
 
 @cindex programming conventions, @code{exit} statement
 For example, suppose an error condition occurs that is difficult or
@@ -13697,15 +13905,10 @@ Negative values, and values of 127 or greater, may not produce consistent
 results across different operating systems.
 @end quotation
 
-@c ENDOFRANGE csta
-@c ENDOFRANGE acs
-@c ENDOFRANGE accs
 
 @node Built-in Variables
 @section Predefined Variables
-@c STARTOFRANGE bvar
 @cindex predefined variables
-@c STARTOFRANGE varb
 @cindex variables, predefined
 
 Most @command{awk} variables are available to use for your own
@@ -13732,9 +13935,7 @@ their areas of activity.
 
 @node User-modified
 @subsection Built-in Variables That Control @command{awk}
-@c STARTOFRANGE bvaru
 @cindex predefined variables, user-modifiable
-@c STARTOFRANGE nmbv
 @cindex user-modifiable variables
 
 The following is an alphabetical list of variables that you can change to
@@ -13762,7 +13963,7 @@ respectively, should use binary I/O.  A string value of @code{"rw"} or
 @code{"wr"} indicates that all files should use binary I/O.  Any other
 string value is treated the same as @code{"rw"}, but causes @command{gawk}
 to generate a warning message.  @code{BINMODE} is described in more
-detail in @ref{PC Using}.  @command{mawk} (@pxref{Other Versions}),
+detail in @ref{PC Using}.  @command{mawk} (@pxref{Other Versions})
 also supports this variable, but only using numeric values.
 
 @cindex @code{CONVFMT} variable
@@ -13770,7 +13971,7 @@ also supports this variable, but only using numeric values.
 @cindex numbers, converting, to strings
 @cindex strings, converting, numbers to
 @item @code{CONVFMT}
-This string controls conversion of numbers to
+A string that controls the conversion of numbers to
 strings (@pxref{Conversion}).
 It works by being passed, in effect, as the first argument to the
 @code{sprintf()} function
@@ -13788,7 +13989,7 @@ A space-separated list of columns that tells @command{gawk}
 how to split input with fixed columnar boundaries.
 Assigning a value to @code{FIELDWIDTHS}
 overrides the use of @code{FS} and @code{FPAT} for field splitting.
-@xref{Constant Size}, for more information.
+@DBXREF{Constant Size} for more information.
 
 @cindex @command{gawk}, @code{FPAT} variable in
 @cindex @code{FPAT} variable
@@ -13800,7 +14001,7 @@ A regular expression (as a string) that tells @command{gawk}
 to create the fields based on text that matches the regular expression.
 Assigning a value to @code{FPAT}
 overrides the use of @code{FS} and @code{FIELDWIDTHS} for field splitting.
-@xref{Splitting By Content}, for more information.
+@DBXREF{Splitting By Content} for more information.
 
 @cindex @code{FS} variable
 @cindex separators, field
@@ -13845,12 +14046,13 @@ is to simply say @samp{FS = FS}, perhaps with an explanatory comment.
 @cindex regular expressions, case sensitivity
 @item IGNORECASE #
 If @code{IGNORECASE} is nonzero or non-null, then all string comparisons
-and all regular expression matching are case independent.  Thus, regexp
-matching with @samp{~} and @samp{!~}, as well as the @code{gensub()},
-@code{gsub()}, @code{index()}, @code{match()}, @code{patsplit()},
-@code{split()}, and @code{sub()}
-functions, record termination with @code{RS}, and field splitting with
-@code{FS} and @code{FPAT}, all ignore case when doing their particular regexp operations.
+and all regular expression matching are case-independent.
+This applies to
+regexp matching with @samp{~} and @samp{!~},
+the @code{gensub()}, @code{gsub()}, @code{index()}, @code{match()},
+@code{patsplit()}, @code{split()}, and @code{sub()} functions,
+record termination with @code{RS}, and field splitting with
+@code{FS} and @code{FPAT}.
 However, the value of @code{IGNORECASE} does @emph{not} affect array subscripting
 and it does not affect field splitting when using a single-character
 field separator.
@@ -13871,7 +14073,7 @@ Any other true value prints nonfatal warnings.
 Assigning a false value to @code{LINT} turns off the lint warnings.
 
 This variable is a @command{gawk} extension.  It is not special
-in other @command{awk} implementations.  Unlike the other special variables,
+in other @command{awk} implementations.  Unlike with the other special variables,
 changing @code{LINT} does affect the production of lint warnings,
 even if @command{gawk} is in compatibility mode.  Much as
 the @option{--lint} and @option{--traditional} options independently
@@ -13883,7 +14085,7 @@ of @command{awk} being executed.
 @cindex numbers, converting, to strings
 @cindex strings, converting, numbers to
 @item OFMT
-Controls conversion of numbers to
+A string that controls conversion of numbers to
 strings (@pxref{Conversion}) for
 printing with the @code{print} statement.  It works by being passed
 as the first argument to the @code{sprintf()} function
@@ -13898,7 +14100,7 @@ strings in general expressions; this is now done by @code{CONVFMT}.
 @cindex separators, field
 @cindex field separators
 @item OFS
-This is the output field separator (@pxref{Output Separators}).  It is
+The output field separator (@pxref{Output Separators}).  It is
 output between the fields printed by a @code{print} statement.  Its
 default value is @w{@code{" "}}, a string consisting of a single space.
 
@@ -13910,13 +14112,13 @@ character.  (@xref{Output Separators}.)
 
 @cindex @code{PREC} variable
 @item PREC #
-The working precision of arbitrary precision floating-point numbers,
+The working precision of arbitrary-precision floating-point numbers,
 53 bits by default (@pxref{Setting precision}).
 
 @cindex @code{ROUNDMODE} variable
 @item ROUNDMODE #
-The rounding mode to use for arbitrary precision arithmetic on
-numbers, by default @code{"N"} (@samp{roundTiesToEven} in
+The rounding mode to use for arbitrary-precision arithmetic on
+numbers, by default @code{"N"} (@code{roundTiesToEven} in
 the IEEE 754 standard; @pxref{Setting the rounding mode}).
 
 @cindex @code{RS} variable
@@ -13945,7 +14147,7 @@ just the first character of @code{RS}'s value is used.
 @item @code{SUBSEP}
 The subscript separator.  It has the default value of
 @code{"\034"} and is used to separate the parts of the indices of a
-multidimensional array.  Thus, the expression @code{@w{foo["A", "B"]}}
+multidimensional array.  Thus, the expression @samp{@w{foo["A", "B"]}}
 really accesses @code{foo["A\034B"]}
 (@pxref{Multidimensional}).
 
@@ -13957,21 +14159,15 @@ really accesses @code{foo["A\034B"]}
 Used for internationalization of programs at the
 @command{awk} level.  It sets the default text domain for specially
 marked string constants in the source text, as well as for the
-@code{dcgettext()}, @code{dcngettext()} and @code{bindtextdomain()} functions
+@code{dcgettext()}, @code{dcngettext()}, and @code{bindtextdomain()} functions
 (@pxref{Internationalization}).
 The default value of @code{TEXTDOMAIN} is @code{"messages"}.
 @end table
-@c ENDOFRANGE bvar
-@c ENDOFRANGE varb
-@c ENDOFRANGE bvaru
-@c ENDOFRANGE nmbv
 
 @node Auto-set
 @subsection Built-in Variables That Convey Information
 
-@c STARTOFRANGE bvconi
 @cindex predefined variables, conveying information
-@c STARTOFRANGE vbconi
 @cindex variables, predefined conveying information
 The following is an alphabetical list of variables that @command{awk}
 sets automatically on certain occasions in order to provide
@@ -13980,7 +14176,7 @@ information to your program.
 The variables that are specific to @command{gawk} are marked with a pound
 sign (@samp{#}).  These variables are @command{gawk} extensions.  In other
 @command{awk} implementations or if @command{gawk} is in compatibility
-mode (@pxref{Options}), they are not special.
+mode (@pxref{Options}), they are not special:
 
 @c @asis for docbook
 @table @asis
@@ -14021,7 +14217,7 @@ method of accessing command-line arguments.
 The value of @code{ARGV[0]} can vary from system to system.
 Also, you should note that the program text is @emph{not} included in
 @code{ARGV}, nor are any of @command{awk}'s command-line options.
-@xref{ARGC and ARGV}, for information
+@DBXREF{ARGC and ARGV} for information
 about how @command{awk} uses these variables.
 @value{DARKCORNER}
 
@@ -14063,12 +14259,23 @@ that it creates.  You should therefore be especially careful if you
 modify @code{ENVIRON["PATH"]"}, which is the search path for finding
 executable programs.
 
+This can also affect the running @command{gawk} program, since some of the
+built-in functions may pay attention to certain environment variables.
+The most notable instance of this is @code{mktime()} (@pxref{Time
+Functions}), which pays attention the value of the @env{TZ} environment
+variable on many systems.
+
 Some operating systems may not have environment variables.
 On such systems, the @code{ENVIRON} array is empty (except for
 @w{@code{ENVIRON["AWKPATH"]}} and
 @w{@code{ENVIRON["AWKLIBPATH"]}};
-@pxref{AWKPATH Variable}, and
+@DBPXREF{AWKPATH Variable} and
+@ifdocbook
+@DBREF{AWKLIBPATH Variable}).
+@end ifdocbook
+@ifnotdocbook
 @pxref{AWKLIBPATH Variable}).
+@end ifnotdocbook
 
 @cindex @command{gawk}, @code{ERRNO} variable in
 @cindex @code{ERRNO} variable
@@ -14090,6 +14297,11 @@ value to be meaningful when an I/O operation returns a failure value,
 such as @code{getline} returning @minus{}1.  You are, of course, free
 to clear it yourself before doing an I/O operation.
 
+If the value of @code{ERRNO} corresponds to a system error in the C
+@code{errno} variable, then @code{PROCINFO["errno"]} will be set to the value
+of @code{errno}.  For non-system errors, @code{PROCINFO["errno"]} will
+be zero.
+
 @cindex @code{FILENAME} variable
 @cindex dark corner, @code{FILENAME} variable
 @item @code{FILENAME}
@@ -14097,7 +14309,7 @@ The name of the current input file.  When no @value{DF}s are listed
 on the command line, @command{awk} reads from the standard input and
 @code{FILENAME} is set to @code{"-"}.  @code{FILENAME} changes each
 time a new file is read (@pxref{Reading Files}).  Inside a @code{BEGIN}
-rule, the value of @code{FILENAME} is @code{""}, since there are no input
+rule, the value of @code{FILENAME} is @code{""}, because there are no input
 files being processed yet.@footnote{Some early implementations of Unix
 @command{awk} initialized @code{FILENAME} to @code{"-"}, even if there
 were @value{DF}s to be processed. This behavior was incorrect and should
@@ -14116,12 +14328,12 @@ input file.
 @item @code{NF}
 The number of fields in the current input record.
 @code{NF} is set each time a new record is read, when a new field is
-created or when @code{$0} changes (@pxref{Fields}).
+created, or when @code{$0} changes (@pxref{Fields}).
 
 Unlike most of the variables described in this @value{SUBSECTION},
 assigning a value to @code{NF} has the potential to affect
 @command{awk}'s internal workings.  In particular, assignments
-to @code{NF} can be used to create or remove fields from the
+to @code{NF} can be used to create fields in or remove fields from the
 current record. @xref{Changing Fields}.
 
 @cindex @code{FUNCTAB} array
@@ -14129,7 +14341,7 @@ current record. @xref{Changing Fields}.
 @cindex differences in @command{awk} and @command{gawk}, @code{FUNCTAB} variable
 @item @code{FUNCTAB #}
 An array whose indices and corresponding values are the names of all
-the built-in, user-defined and extension functions in the program.
+the built-in, user-defined, and extension functions in the program.
 
 @quotation NOTE
 Attempting to use the @code{delete} statement with the @code{FUNCTAB}
@@ -14158,6 +14370,10 @@ are guaranteed to be available:
 @item PROCINFO["egid"]
 The value of the @code{getegid()} system call.
 
+@item PROCINFO["errno"]
+The value of the C @code{errno} variable when @code{ERRNO} is set to
+the associated error message.
+
 @item PROCINFO["euid"]
 @cindex effective user ID of @command{gawk} user
 The value of the @code{geteuid()} system call.
@@ -14171,7 +14387,7 @@ or @code{"FPAT"} if field matching with @code{FPAT} is in effect.
 @item PROCINFO["identifiers"]
 @cindex program identifiers
 A subarray, indexed by the names of all identifiers used in the text of
-the AWK program.  An @dfn{identifier} is simply the name of a variable
+the @command{awk} program.  An @dfn{identifier} is simply the name of a variable
 (be it scalar or array), built-in function, user-defined function, or
 extension function.  For each identifier, the value of the element is
 one of the following:
@@ -14191,7 +14407,7 @@ The identifier is an extension function loaded via
 The identifier is a scalar.
 
 @item "untyped"
-The identifier is untyped (could be used as a scalar or array,
+The identifier is untyped (could be used as a scalar or an array;
 @command{gawk} doesn't know yet).
 
 @item "user"
@@ -14208,7 +14424,7 @@ while the program runs.
 The value of the @code{getgid()} system call.
 
 @item PROCINFO["pgrpid"]
-@cindex process group idIDof @command{gawk} process
+@cindex process group ID of @command{gawk} process
 The process group ID of the current process.
 
 @item PROCINFO["pid"]
@@ -14223,7 +14439,7 @@ The parent process ID of the current process.
 If this element exists in @code{PROCINFO}, its value controls the
 order in which array indices will be processed by
 @samp{for (@var{indx} in @var{array})} loops.
-Since this is an advanced feature, we defer the
+This is an advanced feature, so we defer the
 full description until later; see
 @ref{Scanning an Array}.
 
@@ -14243,10 +14459,10 @@ The version of @command{gawk}.
 
 The following additional elements in the array
 are available to provide information about the MPFR and GMP libraries
-if your version of @command{gawk} supports arbitrary precision arithmetic
-(@pxref{Arbitrary Precision Arithmetic}): 
+if your version of @command{gawk} supports arbitrary-precision arithmetic
+(@pxref{Arbitrary Precision Arithmetic}):
 
-@table @code 
+@table @code
 @cindex version of GNU MPFR library
 @item PROCINFO["mpfr_version"]
 The version of the GNU MPFR library.
@@ -14260,7 +14476,7 @@ The version of the GNU MP library.
 The maximum precision supported by MPFR.
 
 @item PROCINFO["prec_min"]
-@cindex minimum precision supported by MPFR library
+@cindex minimum precision required by MPFR library
 The minimum precision required by MPFR.
 @end table
 
@@ -14294,7 +14510,12 @@ The @code{PROCINFO} array has the following additional uses:
 @item
 It may be used to provide a timeout when reading from any
 open input file, pipe, or coprocess.
-@xref{Read Timeout}, for more information.
+@DBXREF{Read Timeout} for more information.
+
+@item
+It may be used to indicate that input may be retried when it fails due to
+certain errors.
+@DBXREF{Retrying Input} for more information.
 
 @item
 It may be used to cause coprocesses to communicate over pseudo-ttys
@@ -14312,7 +14533,7 @@ is the length of the matched string, or @minus{}1 if no match is found.
 
 @cindex @code{RSTART} variable
 @item @code{RSTART}
-The start-index in characters of the substring that is matched by the
+The start index in characters of the substring that is matched by the
 @code{match()} function
 (@pxref{String Functions}).
 @code{RSTART} is set by invoking the @code{match()} function.  Its value
@@ -14379,11 +14600,9 @@ function multiply(variable, amount)
 @quotation NOTE
 In order to avoid severe time-travel paradoxes,@footnote{Not to mention difficult
 implementation issues.} neither @code{FUNCTAB} nor @code{SYMTAB}
-are available as elements within the @code{SYMTAB} array.
+is available as an element within the @code{SYMTAB} array.
 @end quotation
 @end table
-@c ENDOFRANGE bvconi
-@c ENDOFRANGE vbconi
 
 @sidebar Changing @code{NR} and @code{FNR}
 @cindex @code{NR} variable, changing
@@ -14493,8 +14712,14 @@ use the @code{delete} statement to remove elements from
 
 All of these actions are typically done in the @code{BEGIN} rule,
 before actual processing of the input begins.
-@xref{Split Program}, and see
-@ref{Tee Program}, for examples
+@DBXREF{Split Program} and
+@ifnotdocbook
+@DBPXREF{Tee Program}
+@end ifnotdocbook
+@ifdocbook
+@DBREF{Tee Program}
+@end ifdocbook
+for examples
 of each way of removing elements from @code{ARGV}.
 
 To actually get options into an @command{awk} program,
@@ -14506,7 +14731,7 @@ awk -f myprog.awk -- -v -q file1 file2 @dots{}
 @end example
 
 The following fragment processes @code{ARGV} in order to examine, and
-then remove, the above command-line options:
+then remove, the previously mentioned command-line options:
 
 @example
 BEGIN @{
@@ -14542,29 +14767,36 @@ gawk -f myprog.awk -q -v file1 file2 @dots{}
 @noindent
 Because @option{-q} is not a valid @command{gawk} option, it and the
 following @option{-v} are passed on to the @command{awk} program.
-(@xref{Getopt Function}, for an @command{awk} library function that
+(@DBXREF{Getopt Function} for an @command{awk} library function that
 parses command-line options.)
 
 When designing your program, you should choose options that don't
-conflict with @command{gawk}'s, since it will process any options
+conflict with @command{gawk}'s, because it will process any options
 that it accepts before passing the rest of the command line on to
 your program.  Using @samp{#!} with the @option{-E} option may help
-(@pxref{Executable Scripts}, and @pxref{Options}).
+(@DBPXREF{Executable Scripts}
+and
+@ifnotdocbook
+@DBPXREF{Options}).
+@end ifnotdocbook
+@ifdocbook
+@DBREF{Options}).
+@end ifdocbook
 
 @node Pattern Action Summary
 @section Summary
 
 @itemize @value{BULLET}
 @item
-Pattern-action pairs make up the basic elements of an @command{awk}
+Pattern--action pairs make up the basic elements of an @command{awk}
 program.  Patterns are either normal expressions, range expressions,
-regexp constants, one of the special keywords @code{BEGIN}, @code{END},
-@code{BEGINFILE}, @code{ENDFILE}, or empty.  The action executes if
+or regexp constants; one of the special keywords @code{BEGIN}, @code{END},
+@code{BEGINFILE}, or @code{ENDFILE}; or empty.  The action executes if
 the current record matches the pattern.  Empty (missing) patterns match
 all records.
 
 @item
-I/O from @code{BEGIN} and @code{END} rules have certain constraints.
+I/O from @code{BEGIN} and @code{END} rules has certain constraints.
 This is also true, only more so, for @code{BEGINFILE} and @code{ENDFILE}
 rules.  The latter two give you ``hooks'' into @command{gawk}'s file
 processing, allowing you to recover from a file that otherwise would
@@ -14594,12 +14826,12 @@ iteration of a loop (or get out of a @code{switch}).
 
 @item
 @code{next} and @code{nextfile} let you read the next record and start
-over at the top of your program, or skip to the next input file and
+over at the top of your program or skip to the next input file and
 start over, respectively.
 
 @item
 The @code{exit} statement terminates your program. When executed
-from an action (or function body) it transfers control to the
+from an action (or function body), it transfers control to the
 @code{END} statements. From an @code{END} statement body, it exits
 immediately.  You may pass an optional numeric value to be used
 as @command{awk}'s exit status.
@@ -14617,7 +14849,6 @@ control how @command{awk} will process the provided @value{DF}s.
 
 @node Arrays
 @chapter Arrays in @command{awk}
-@c STARTOFRANGE arrs
 @cindex arrays
 
 An @dfn{array} is a table of values called @dfn{elements}.  The
@@ -14692,7 +14923,7 @@ In most other languages, arrays must be @dfn{declared} before use,
 including a specification of
 how many elements or components they contain.  In such languages, the
 declaration causes a contiguous block of memory to be allocated for that
-many elements.  Usually, an index in the array must be a positive integer.
+many elements.  Usually, an index in the array must be a nonnegative integer.
 For example, the index zero specifies the first element in the array, which is
 actually stored at the beginning of the block of memory.  Index one
 specifies the second element, which is stored in memory right after the
@@ -14703,19 +14934,21 @@ the declaration.
 indices---e.g., @samp{15 .. 27}---but the size of the array is still fixed when
 the array is declared.)
 
-A contiguous array of four elements might look like the following example,
-conceptually, if the element values are 8, @code{"foo"},
-@code{""}, and 30
+@c 1/2015: Do not put the numeric values into @code. Array element
+@c values are no different than scalar variable values.
+A contiguous array of four elements might look like
 @ifnotdocbook
-as shown in @ref{figure-array-elements}:
+@ref{figure-array-elements},
 @end ifnotdocbook
 @ifdocbook
-as shown in @inlineraw{docbook, <xref linkend="figure-array-elements"/>}:
+@inlineraw{docbook, <xref linkend="figure-array-elements"/>},
 @end ifdocbook
+conceptually, if the element values are eight, @code{"foo"},
+@code{""}, and 30.
 
 @ifnotdocbook
 @float Figure,figure-array-elements
-@caption{A Contiguous Array}
+@caption{A contiguous array}
 @ifinfo
 @center @image{array-elements, , , Basic Program Stages, txt}
 @end ifinfo
@@ -14727,7 +14960,7 @@ as shown in @inlineraw{docbook, <xref linkend="figure-array-elements"/>}:
 
 @docbook
 <figure id="figure-array-elements" float="0">
-<title>A Contiguous Array</title>
+<title>A contiguous array</title>
 <mediaobject>
 <imageobject role="web"><imagedata fileref="array-elements.png" format="PNG"/></imageobject>
 </mediaobject>
@@ -14736,33 +14969,33 @@ as shown in @inlineraw{docbook, <xref linkend="figure-array-elements"/>}:
 
 @noindent
 Only the values are stored; the indices are implicit from the order of
-the values. Here, 8 is the value at index zero, because 8 appears in the
+the values. Here, eight is the value at index zero, because eight appears in the
 position with zero elements before it.
 
-@c STARTOFRANGE arrin
 @cindex arrays, indexing
-@c STARTOFRANGE inarr
 @cindex indexing arrays
 @cindex associative arrays
 @cindex arrays, associative
 Arrays in @command{awk} are different---they are @dfn{associative}.  This means
-that each array is a collection of pairs: an index and its corresponding
+that each array is a collection of pairs---an index and its corresponding
 array element value:
 
 @ifnotdocbook
-@example
-@r{Index} 3     @r{Value} 30
-@r{Index} 1     @r{Value} "foo"
-@r{Index} 0     @r{Value} 8
-@r{Index} 2     @r{Value} ""
-@end example
+@c extra empty column to indent it right
+@multitable @columnfractions .1 .1 .1
+@headitem @tab Index @tab Value
+@item @tab @code{3} @tab @code{30}
+@item @tab @code{1} @tab @code{"foo"}
+@item @tab @code{0} @tab @code{8}
+@item @tab @code{2} @tab @code{""}
+@end multitable
 @end ifnotdocbook
 
 @docbook
 <informaltable>
 <tgroup cols="2">
-<colspec colname="1" align="center"/>
-<colspec colname="2" align="center"/>
+<colspec colname="1" align="left"/>
+<colspec colname="2" align="left"/>
 <thead>
 <row>
 <entry>Index</entry>
@@ -14808,20 +15041,22 @@ at any time.  For example, suppose a tenth element is added to the array
 whose value is @w{@code{"number ten"}}.  The result is:
 
 @ifnotdocbook
-@example
-@r{Index} 10    @r{Value} "number ten"
-@r{Index} 3     @r{Value} 30
-@r{Index} 1     @r{Value} "foo"
-@r{Index} 0     @r{Value} 8
-@r{Index} 2     @r{Value} ""
-@end example
+@c extra empty column to indent it right
+@multitable @columnfractions .1 .1 .2
+@headitem @tab Index @tab Value
+@item @tab @code{10} @tab @code{"number ten"}
+@item @tab @code{3} @tab @code{30}
+@item @tab @code{1} @tab @code{"foo"}
+@item @tab @code{0} @tab @code{8}
+@item @tab @code{2} @tab @code{""}
+@end multitable
 @end ifnotdocbook
 
 @docbook
 <informaltable>
 <tgroup cols="2">
-<colspec colname="1" align="center"/>
-<colspec colname="2" align="center"/>
+<colspec colname="1" align="left"/>
+<colspec colname="2" align="left"/>
 <thead>
 <row>
 <entry>Index</entry>
@@ -14868,24 +15103,25 @@ Now the array is @dfn{sparse}, which just means some indices are missing.
 It has elements 0--3 and 10, but doesn't have elements 4, 5, 6, 7, 8, or 9.
 
 Another consequence of associative arrays is that the indices don't
-have to be positive integers.  Any number, or even a string, can be
+have to be nonnegative integers.  Any number, or even a string, can be
 an index.  For example, the following is an array that translates words from
 English to French:
 
 @ifnotdocbook
-@example
-@r{Index} "dog" @r{Value} "chien"
-@r{Index} "cat" @r{Value} "chat"
-@r{Index} "one" @r{Value} "un"
-@r{Index} 1     @r{Value} "un"
-@end example
+@multitable @columnfractions .1 .1 .1
+@headitem @tab Index @tab Value
+@item @tab @code{"dog"} @tab @code{"chien"}
+@item @tab @code{"cat"} @tab @code{"chat"}
+@item @tab @code{"one"} @tab @code{"un"}
+@item @tab @code{1} @tab @code{"un"}
+@end multitable
 @end ifnotdocbook
 
 @docbook
 <informaltable>
 <tgroup cols="2">
-<colspec colname="1" align="center"/>
-<colspec colname="2" align="center"/>
+<colspec colname="1" align="left"/>
+<colspec colname="2" align="left"/>
 <thead>
 <row>
 <entry>Index</entry>
@@ -14927,7 +15163,7 @@ numbers and strings as indices.
 There are some subtleties to how numbers work when used as
 array subscripts; this is discussed in more detail in
 @ref{Numeric Array Subscripts}.)
-Here, the number @code{1} isn't double-quoted, since @command{awk}
+Here, the number @code{1} isn't double-quoted, because @command{awk}
 automatically converts it to a string.
 
 @cindex @command{gawk}, @code{IGNORECASE} variable in
@@ -14944,8 +15180,6 @@ that array's indices are consecutive integers starting at one.
 
 @command{awk}'s arrays are efficient---the time to access an element
 is independent of the number of elements in the array.
-@c ENDOFRANGE arrin
-@c ENDOFRANGE inarr
 
 @node Reference to Elements
 @subsection Referring to an Array Element
@@ -14954,7 +15188,7 @@ is independent of the number of elements in the array.
 @cindex elements of arrays
 
 The principal way to use an array is to refer to one of its elements.
-An array reference is an expression as follows:
+An @dfn{array reference} is an expression as follows:
 
 @example
 @var{array}[@var{index-expression}]
@@ -14964,8 +15198,11 @@ An array reference is an expression as follows:
 Here, @var{array} is the name of an array.  The expression @var{index-expression} is
 the index of the desired element of the array.
 
+@c 1/2015: Having the 4.3 in @samp is a little iffy. It's essentially
+@c an expression though, so leave be. It's to early in the discussion
+@c to mention that it's really a string.
 The value of the array reference is the current value of that array
-element.  For example, @code{foo[4.3]} is an expression for the element
+element.  For example, @code{foo[4.3]} is an expression referencing the element
 of array @code{foo} at index @samp{4.3}.
 
 @cindex arrays, unassigned elements
@@ -15012,7 +15249,7 @@ This expression tests whether the particular index @var{indx} exists,
 without the side effect of creating that element if it is not present.
 The expression has the value one (true) if @code{@var{array}[@var{indx}]}
 exists and zero (false) if it does not exist.
-(We use @var{indx} here, since @samp{index} is the name of a built-in
+(We use @var{indx} here, because @samp{index} is the name of a built-in
 function.)
 For example, this statement tests whether the array @code{frequencies}
 contains the index @samp{2}:
@@ -15057,7 +15294,7 @@ assign to that element of the array.
 
 The following program takes a list of lines, each beginning with a line
 number, and prints them out in order of line number.  The line numbers
-are not in order when they are first read---instead they
+are not in order when they are first read---instead, they
 are scrambled.  This program sorts the lines by making an array using
 the line numbers as subscripts.  The program then prints out the lines
 in sorted order of their numbers.  It is a very simple program and gets
@@ -15129,7 +15366,7 @@ END @{
 
 In programs that use arrays, it is often necessary to use a loop that
 executes once for each element of an array.  In other languages, where
-arrays are contiguous and indices are limited to positive integers,
+arrays are contiguous and indices are limited to nonnegative integers,
 this is easy: all the valid indices can be found by counting from
 the lowest index up to the highest.  This technique won't do the job
 in @command{awk}, because any number or string can be an array index.
@@ -15151,11 +15388,11 @@ program has previously used, with the variable @var{var} set to that index.
 The following program uses this form of the @code{for} statement.  The
 first rule scans the input records and notes which words appear (at
 least once) in the input, by storing a one into the array @code{used} with
-the word as index.  The second rule scans the elements of @code{used} to
+the word as the index.  The second rule scans the elements of @code{used} to
 find all the distinct words that appear in the input.  It prints each
 word that is more than 10 characters long and also prints the number of
 such words.
-@xref{String Functions},
+@DBXREF{String Functions}
 for more information on the built-in function @code{length()}.
 
 @example
@@ -15178,7 +15415,7 @@ END @{
 @end example
 
 @noindent
-@xref{Word Sorting},
+@DBXREF{Word Sorting}
 for a more detailed example of this type.
 
 @cindex arrays, elements, order of access by @code{in} operator
@@ -15233,7 +15470,7 @@ $ @kbd{nawk -f loopcheck.awk}
 @end example
 
 @node Controlling Scanning
-@subsection Using Predefined Array Scanning Orders With @command{gawk}
+@subsection Using Predefined Array Scanning Orders with @command{gawk}
 
 This @value{SUBSECTION} describes a feature that is specific to @command{gawk}.
 
@@ -15248,7 +15485,7 @@ and will vary from one version of @command{awk} to the next.
 Often, though, you may wish to do something simple, such as
 ``traverse the array by comparing the indices in ascending order,''
 or ``traverse the array by comparing the values in descending order.''
-@command{gawk} provides two mechanisms which give you this control.
+@command{gawk} provides two mechanisms that give you this control:
 
 @itemize @value{BULLET}
 @item
@@ -15258,7 +15495,7 @@ We describe this now.
 @item
 Set @code{PROCINFO["sorted_in"]} to the name of a user-defined function
 to use for comparison of array elements. This advanced feature
-is described later, in @ref{Array Sorting}.
+is described later in @ref{Array Sorting}.
 @end itemize
 
 @cindex @code{PROCINFO}, values of @code{sorted_in}
@@ -15276,7 +15513,7 @@ the index is @code{"10"} rather than numeric 10.)
 
 @item "@@ind_num_asc"
 Order by indices in ascending order but force them to be treated as numbers in the process.
-Any index with a non-numeric value will end up positioned as if it were zero. 
+Any index with a non-numeric value will end up positioned as if it were zero.
 
 @item "@@val_type_asc"
 Order by element values in ascending order (rather than by indices).
@@ -15288,11 +15525,11 @@ which in turn come before all subarrays.
 @pxref{Arrays of Arrays}.)
 
 @item "@@val_str_asc"
-Order by element values in ascending order (rather than by indices).  Scalar values are 
+Order by element values in ascending order (rather than by indices).  Scalar values are
 compared as strings.  Subarrays, if present, come out last.
 
 @item "@@val_num_asc"
-Order by element values in ascending order (rather than by indices).  Scalar values are 
+Order by element values in ascending order (rather than by indices).  Scalar values are
 compared as numbers.  Subarrays, if present, come out last.
 When numeric values are equal, the string values are used to provide
 an ordering: this guarantees consistent results across different
@@ -15305,21 +15542,26 @@ across different environments.} which @command{gawk} uses internally
 to perform the sorting.
 
 @item "@@ind_str_desc"
-String indices ordered from high to low.
+Like @code{"@@ind_str_asc"}, but the
+string indices are ordered from high to low.
 
 @item "@@ind_num_desc"
-Numeric indices ordered from high to low.
+Like @code{"@@ind_num_asc"}, but the
+numeric indices are ordered from high to low.
 
 @item "@@val_type_desc"
-Element values, based on type, ordered from high to low.
+Like @code{"@@val_type_asc"}, but the
+element values, based on type, are ordered from high to low.
 Subarrays, if present, come out first.
 
 @item "@@val_str_desc"
-Element values, treated as strings, ordered from high to low.
+Like @code{"@@val_str_asc"}, but the
+element values, treated as strings, are ordered from high to low.
 Subarrays, if present, come out first.
 
 @item "@@val_num_desc"
-Element values, treated as numbers, ordered from high to low.
+Like @code{"@@val_num_asc"}, but the
+element values, treated as numbers, are ordered from high to low.
 Subarrays, if present, come out first.
 @end table
 
@@ -15353,11 +15595,11 @@ $ @kbd{gawk '}
 When sorting an array by element values, if a value happens to be
 a subarray then it is considered to be greater than any string or
 numeric value, regardless of what the subarray itself contains,
-and all subarrays are treated as being equal to each other.  Their 
+and all subarrays are treated as being equal to each other.  Their
 order relative to each other is determined by their index strings.
 
 Here are some additional things to bear in mind about sorted
-array traversal.
+array traversal:
 
 @itemize @value{BULLET}
 @item
@@ -15377,7 +15619,7 @@ if (save_sorted)
 @end example
 
 @item
-As mentioned, the default array traversal order is represented by
+As already mentioned, the default array traversal order is represented by
 @code{"@@unsorted"}.  You can also get the default behavior by assigning
 the null string to @code{PROCINFO["sorted_in"]} or by just deleting the
 @code{"sorted_in"} element from the @code{PROCINFO} array with
@@ -15422,7 +15664,7 @@ The program then changes
 the value of @code{CONVFMT}.  The test @samp{(xyz in data)} generates a new
 string value from @code{xyz}---this time @code{"12.15"}---because the value of
 @code{CONVFMT} only allows two significant digits.  This test fails,
-since @code{"12.15"} is different from @code{"12.153"}.
+because @code{"12.15"} is different from @code{"12.153"}.
 
 @cindex converting integer array subscripts
 @cindex integer array indices
@@ -15440,19 +15682,19 @@ for (i = 1; i <= maxsub; i++)
 The ``integer values always convert to strings as integers'' rule
 has an additional consequence for array indexing.
 Octal and hexadecimal constants
+@ifnotdocbook
 (@pxref{Nondecimal-numbers})
+@end ifnotdocbook
+@ifdocbook
+(covered in @ref{Nondecimal-numbers})
+@end ifdocbook
 are converted internally into numbers, and their original form
-is forgotten.
-This means, for example, that
-@code{array[17]},
-@code{array[021]},
-and
-@code{array[0x11]}
-all refer to the same element!
+is forgotten.  This means, for example, that @code{array[17]},
+@code{array[021]}, and @code{array[0x11]} all refer to the same element!
 
 As with many things in @command{awk}, the majority of the time
 things work as you would expect them to.  But it is useful to have a precise
-knowledge of the actual rules since they can sometimes have a subtle
+knowledge of the actual rules, as they can sometimes have a subtle
 effect on your programs.
 
 @node Uninitialized Subscripts
@@ -15542,7 +15784,7 @@ for (i in frequencies)
 @noindent
 This example removes all the elements from the array @code{frequencies}.
 Once an element is deleted, a subsequent @code{for} statement to scan the array
-does not report that element and the @code{in} operator to check for
+does not report that element and using the @code{in} operator to check for
 the presence of that element returns zero (i.e., false):
 
 @example
@@ -15595,7 +15837,7 @@ by a number of other implementations.
 @cindex Brian Kernighan's @command{awk}
 @quotation NOTE
 For many years, using @code{delete} without a subscript was a common
-extension.  In September, 2012, it was accepted for inclusion into the
+extension.  In September 2012, it was accepted for inclusion into the
 POSIX standard.  See @uref{http://austingroupbugs.net/view.php?id=544,
 the Austin Group website}.
 @end quotation
@@ -15637,7 +15879,7 @@ a = 3
 
 @cindex subscripts in arrays, multidimensional
 @cindex arrays, multidimensional
-A multidimensional array is an array in which an element is identified
+A @dfn{multidimensional array} is an array in which an element is identified
 by a sequence of indices instead of a single index.  For example, a
 two-dimensional array requires two indices.  The usual way (in many
 languages, including @command{awk}) to refer to an element of a
@@ -15679,7 +15921,7 @@ stored as @samp{foo["a@@b@@c"]}.
 @cindex @code{in} operator, index existence in multidimensional arrays
 To test whether a particular index sequence exists in a
 multidimensional array, use the same operator (@code{in}) that is
-used for single dimensional arrays.  Write the whole sequence of indices
+used for single-dimensional arrays.  Write the whole sequence of indices
 in parentheses, separated by commas, as the left operand:
 
 @example
@@ -15802,8 +16044,8 @@ a[1][2] = 2
 This simulates a true two-dimensional array. Each subarray element can
 contain another subarray as a value, which in turn can hold other arrays
 as well. In this way, you can create arrays of three or more dimensions.
-The indices can be any @command{awk} expression, including scalars
-separated by commas (that is, a regular @command{awk} simulated
+The indices can be any @command{awk} expressions, including scalars
+separated by commas (i.e., a regular @command{awk} simulated
 multidimensional subscript). So the following is valid in
 @command{gawk}:
 
@@ -15814,15 +16056,15 @@ a[1][3][1, "name"] = "barney"
 Each subarray and the main array can be of different length. In fact, the
 elements of an array or its subarray do not all have to have the same
 type. This means that the main array and any of its subarrays can be
-non-rectangular, or jagged in structure. You can assign a scalar value to
+nonrectangular, or jagged in structure. You can assign a scalar value to
 the index @code{4} of the main array @code{a}, even though @code{a[1]}
 is itself an array and not a scalar:
 
 @example
 a[4] = "An element in a jagged array"
 @end example
-  
-The terms @dfn{dimension}, @dfn{row} and @dfn{column} are
+
+The terms @dfn{dimension}, @dfn{row}, and @dfn{column} are
 meaningless when applied
 to such an array, but we will use ``dimension'' henceforth to imply the
 maximum number of indices needed to refer to an existing element. The
@@ -15838,7 +16080,8 @@ a[4][5][6][7] = "An element in a four-dimensional array"
 
 @noindent
 This removes the scalar value from index @code{4} and then inserts a
-subarray of subarray of subarray containing a scalar. You can also
+three-level nested subarray
+containing a scalar. You can also
 delete an entire subarray or subarray of subarrays:
 
 @example
@@ -15849,7 +16092,7 @@ a[4][5] = "An element in subarray a[4]"
 But recall that you can not delete the main array @code{a} and then use it
 as a scalar.
 
-The built-in functions which take array arguments can also be used
+The built-in functions that take array arguments can also be used
 with subarrays. For example, the following code fragment uses @code{length()}
 (@pxref{String Functions})
 to determine the number of elements in the main array @code{a} and
@@ -15878,14 +16121,14 @@ The @samp{for (item in array)} statement (@pxref{Scanning an Array})
 can be nested to scan all the
 elements of an array of arrays if it is rectangular in structure. In order
 to print the contents (scalar values) of a two-dimensional array of arrays
-(i.e., in which each first-level element is itself an 
-array, not necessarily of the same length) 
+(i.e., in which each first-level element is itself an
+array, not necessarily of the same length),
 you could use the following code:
 
 @example
 for (i in array)
     for (j in array[i])
-        print array[i][j] 
+        print array[i][j]
 @end example
 
 The @code{isarray()} function (@pxref{Type Functions})
@@ -15895,7 +16138,7 @@ lets you test if an array element is itself an array:
 for (i in array) @{
     if (isarray(array[i]) @{
         for (j in array[i]) @{
-            print array[i][j] 
+            print array[i][j]
         @}
     @}
     else
@@ -15905,7 +16148,7 @@ for (i in array) @{
 
 If the structure of a jagged array of arrays is known in advance,
 you can often devise workarounds using control statements. For example,
-the following code prints the elements of our main array @code{a}: 
+the following code prints the elements of our main array @code{a}:
 
 @example
 for (i in a) @{
@@ -15915,13 +16158,13 @@ for (i in a) @{
                 print a[i][j][k]
         @} else
             print a[i][j]
-    @} 
+    @}
 @}
 @end example
 
 @noindent
-@xref{Walking Arrays}, for a user-defined function that ``walks'' an
-arbitrarily-dimensioned array of arrays.
+@DBXREF{Walking Arrays} for a user-defined function that ``walks'' an
+arbitrarily dimensioned array of arrays.
 
 Recall that a reference to an uninitialized array element yields a value
 of @code{""}, the null string. This has one important implication when you
@@ -15971,16 +16214,17 @@ special predefined values to @code{PROCINFO["sorted_in"]}.
 
 @item
 Use @samp{delete @var{array}[@var{indx}]} to delete an individual element.
-You may also use @samp{delete @var{array}} to delete all of the elements
-in the array.  This latter feature has been a common extension for many
+To delete all of the elements in an array,
+use @samp{delete @var{array}}.
+This latter feature has been a common extension for many
 years and is now standard, but may not be supported by all commercial
 versions of @command{awk}.
 
 @item
 Standard @command{awk} simulates multidimensional arrays by separating
-subscript values with a comma.  The values are concatenated into a
+subscript values with commas.  The values are concatenated into a
 single string, separated by the value of @code{SUBSEP}.  The fact
-that such a subscript was created in this way is not retained; thus
+that such a subscript was created in this way is not retained; thus,
 changing @code{SUBSEP} may have unexpected consequences.  You can use
 @samp{(@var{sub1}, @var{sub2}, @dots{}) in @var{array}} to see if such
 a multidimensional subscript exists in @var{array}.
@@ -15989,7 +16233,7 @@ a multidimensional subscript exists in @var{array}.
 @command{gawk} provides true arrays of arrays. You use a separate
 set of square brackets for each dimension in such an array:
 @code{data[row][col]}, for example. Array elements may thus be either
-scalar values (number or string) or another array.
+scalar values (number or string) or other arrays.
 
 @item
 Use the @code{isarray()} built-in function to determine if an array
@@ -15997,25 +16241,26 @@ element is itself a subarray.
 
 @end itemize
 
-@c ENDOFRANGE arrs
 
 @node Functions
 @chapter Functions
 
-@c STARTOFRANGE funcbi
 @cindex functions, built-in
-@c STARTOFRANGE bifunc
 @cindex built-in functions
 This @value{CHAPTER} describes @command{awk}'s built-in functions,
 which fall into three categories: numeric, string, and I/O.
 @command{gawk} provides additional groups of functions
 to work with values that represent time, do
-bit manipulation, sort arrays, and internationalize and localize programs.
+bit manipulation, sort arrays,
+provide type information, and internationalize and localize programs.
 
 Besides the built-in functions, @command{awk} has provisions for
 writing new functions that the rest of a program can use.
 The second half of this @value{CHAPTER} describes these
 @dfn{user-defined} functions.
+Finally, we explore indirect function calls, a @command{gawk}-specific
+extension that lets you determine at runtime what function is to
+be called.
 
 @menu
 * Built-in::                    Summarizes the built-in functions.
@@ -16058,7 +16303,7 @@ is a call to the function @code{atan2()} and has two arguments.
 @cindex programming conventions, functions, calling
 @cindex whitespace, functions@comma{} calling
 Whitespace is ignored between the built-in function name and the
-open parenthesis, but nonetheless it is good practice to avoid using whitespace
+opening parenthesis, but nonetheless it is good practice to avoid using whitespace
 there.  User-defined functions do not permit whitespace in this way, and
 it is easier to avoid mistakes by following a simple
 convention that always works---no whitespace after a function name.
@@ -16095,11 +16340,11 @@ right to left.  For example:
 
 @example
 i = 5
-j = atan2(i++, i *= 2)
+j = atan2(++i, i *= 2)
 @end example
 
 If the order of evaluation is left to right, then @code{i} first becomes
-6, and then 12, and @code{atan2()} is called with the two arguments 6
+six, and then 12, and @code{atan2()} is called with the two arguments six
 and 12.  But if the order of evaluation is right to left, @code{i}
 first becomes 10, then 11, and @code{atan2()} is called with the
 two arguments 11 and 10.
@@ -16126,23 +16371,6 @@ You can use @samp{pi = atan2(0, -1)} to retrieve the value of
 @cindex cosine
 Return the cosine of @var{x}, with @var{x} in radians.
 
-@item @code{div(@var{numerator}, @var{denominator}, @var{result})}
-@cindexawkfunc{div}
-@cindex div
-Perform integer division, similar to the standard C function of the
-same name.  First, truncate @code{numerator} and @code{denominator}
-towards zero, creating integer values.  Clear the @code{result}
-array, and then set @code{result["quotient"]} to the result of
-@samp{numerator / denominator}, truncated towards zero to an integer,
-and set @code{result["remainder"]} to the result of @samp{numerator %
-denominator}, truncated towards zero to an integer.  This function is
-primarily intended for use with arbitrary length integers; it avoids
-creating MPFR arbitrary precision floating-point values (@pxref{Arbitrary
-Precision Integers}).
-
-This function is a @code{gawk} extension.  It is not available in
-compatibility mode (@pxref{Options}).
-
 @item @code{exp(@var{x})}
 @cindexawkfunc{exp}
 @cindex exponent
@@ -16155,10 +16383,26 @@ depends on your machine's floating-point representation.
 @cindex round to nearest integer
 Return the nearest integer to @var{x}, located between @var{x} and zero and
 truncated toward zero.
-
 For example, @code{int(3)} is 3, @code{int(3.9)} is 3, @code{int(-3.9)}
 is @minus{}3, and @code{int(-3)} is @minus{}3 as well.
 
+@item @code{intdiv(@var{numerator}, @var{denominator}, @var{result})}
+@cindexawkfunc{intdiv}
+@cindex intdiv
+Perform integer division, similar to the standard C function of the
+same name.  First, truncate @code{numerator} and @code{denominator}
+towards zero, creating integer values.  Clear the @code{result}
+array, and then set @code{result["quotient"]} to the result of
+@samp{numerator / denominator}, truncated towards zero to an integer,
+and set @code{result["remainder"]} to the result of @samp{numerator %
+denominator}, truncated towards zero to an integer.  This function is
+primarily intended for use with arbitrary length integers; it avoids
+creating MPFR arbitrary precision floating-point values (@pxref{Arbitrary
+Precision Integers}).
+
+This function is a @code{gawk} extension.  It is not available in
+compatibility mode (@pxref{Options}).
+
 @item @code{log(@var{x})}
 @cindexawkfunc{log}
 @cindex logarithm
@@ -16181,7 +16425,7 @@ In fact, @command{gawk} uses the BSD @code{random()} function, which is
 considerably better than @code{rand()}, to produce random numbers.}
 
 Often random integers are needed instead.  Following is a user-defined function
-that can be used to obtain a random non-negative integer less than @var{n}:
+that can be used to obtain a random nonnegative integer less than @var{n}:
 
 @example
 function randint(n)
@@ -16191,8 +16435,8 @@ function randint(n)
 @end example
 
 @noindent
-The multiplication produces a random number greater than zero and less
-than @code{n}.  Using @code{int()}, this result is made into
+The multiplication produces a random number greater than or equal to
+zero and less than @code{n}.  Using @code{int()}, this result is made into
 an integer between zero and @code{n} @minus{} 1, inclusive.
 
 The following example uses a similar function to produce random integers
@@ -16244,8 +16488,8 @@ for generating random numbers to the value @var{x}.
 
 Each seed value leads to a particular sequence of random
 numbers.@footnote{Computer-generated random numbers really are not truly
-random.  They are technically known as ``pseudorandom.''  This means
-that while the numbers in a sequence appear to be random, you can in
+random.  They are technically known as @dfn{pseudorandom}.  This means
+that although the numbers in a sequence appear to be random, you can in
 fact generate the same sequence of random numbers over and over again.}
 Thus, if the seed is set to the same value a second time,
 the same sequence of random numbers is produced again.
@@ -16276,7 +16520,7 @@ implementations.
 The functions in this @value{SECTION} look at or change the text of one
 or more strings.
 
-@code{gawk} understands locales (@pxref{Locales}), and does all
+@command{gawk} understands locales (@pxref{Locales}) and does all
 string processing in terms of @emph{characters}, not @emph{bytes}.
 This distinction is particularly important to understand for locales
 where one character may be represented by multiple bytes.  Thus, for
@@ -16295,7 +16539,7 @@ doing index calculations, particularly if you are used to C.
 In the following list, optional parameters are enclosed in square brackets@w{ ([ ]).}
 Several functions perform string substitution; the full discussion is
 provided in the description of the @code{sub()} function, which comes
-towards the end since the list is presented alphabetically.
+toward the end, because the list is presented alphabetically.
 
 Those functions that are specific to @command{gawk} are marked with a
 pound sign (@samp{#}).  They are not available in compatibility mode
@@ -16321,10 +16565,10 @@ These two functions are similar in behavior, so they are described
 together.
 
 @quotation NOTE
-The following description ignores the third argument, @var{how}, since it
+The following description ignores the third argument, @var{how}, as it
 requires understanding features that we have not discussed yet.  Thus,
 the discussion here is a deliberate simplification.  (We do provide all
-the details later on: @xref{Array Sorting Functions}, for the full story.)
+the details later on; see @DBREF{Array Sorting Functions} for the full story.)
 @end quotation
 
 Both functions return the number of elements in the array @var{source}.
@@ -16365,7 +16609,7 @@ a[2] = "de"
 a[3] = "sac"
 @end example
 
-The @code{asorti()} function works similarly to @code{asort()}, however,
+The @code{asorti()} function works similarly to @code{asort()}; however,
 the @emph{indices} are sorted, instead of the values. Thus, in the
 previous example, starting with the same initial set of indices and
 values in @code{a}, calling @samp{asorti(a)} would yield:
@@ -16476,10 +16720,11 @@ $ @kbd{awk 'BEGIN @{ print index("peanut", "an") @}'}
 @noindent
 If @var{find} is not found, @code{index()} returns zero.
 
+@cindex dark corner, regexp as second argument to @code{index()}
 With BWK @command{awk} and @command{gawk},
 it is a fatal error to use a regexp constant for @var{find}.
 Other implementations allow it, simply treating the regexp
-constant as an expression meaning @samp{$0 ~ /regexp/}. @value{DARKCORNER}.
+constant as an expression meaning @samp{$0 ~ /regexp/}. @value{DARKCORNER}
 
 @item @code{length(}[@var{string}]@code{)}
 @cindexawkfunc{length}
@@ -16562,7 +16807,7 @@ If @option{--posix} is supplied, using an array argument is a fatal error
 @cindex string, regular expression match
 @cindex match regexp in string
 Search @var{string} for the
-longest, leftmost substring matched by the regular expression,
+longest, leftmost substring matched by the regular expression
 @var{regexp} and return the character position (index)
 at which that substring begins (one, if it starts at the beginning of
 @var{string}).  If no match is found, return zero.
@@ -16570,11 +16815,11 @@ at which that substring begins (one, if it starts at the beginning of
 The @var{regexp} argument may be either a regexp constant
 (@code{/}@dots{}@code{/}) or a string constant (@code{"}@dots{}@code{"}).
 In the latter case, the string is treated as a regexp to be matched.
-@xref{Computed Regexps}, for a
+@DBXREF{Computed Regexps} for a
 discussion of the difference between the two forms, and the
 implications for writing your program correctly.
 
-The order of the first two arguments is backwards from most other string
+The order of the first two arguments is the opposite of most other string
 functions that work with regular expressions, such as
 @code{sub()} and @code{gsub()}.  It might help to remember that
 for @code{match()}, the order is the same as for the @samp{~} operator:
@@ -16663,7 +16908,7 @@ $ @kbd{echo foooobazbarrrrr |}
 @end example
 
 There may not be subscripts for the start and index for every parenthesized
-subexpression, since they may not all have matched text; thus they
+subexpression, because they may not all have matched text; thus, they
 should be tested for with the @code{in} operator
 (@pxref{Reference to Elements}).
 
@@ -16710,15 +16955,15 @@ a regexp describing where to split @var{string} (much as @code{FS} can
 be a regexp describing where to split input records).
 If @var{fieldsep} is omitted, the value of @code{FS} is used.
 @code{split()} returns the number of elements created.
-@var{seps} is a @command{gawk} extension with @code{@var{seps}[@var{i}]} 
+@var{seps} is a @command{gawk} extension, with @code{@var{seps}[@var{i}]}
 being the separator string
-between @code{@var{array}[@var{i}]} and @code{@var{array}[@var{i}+1]}. 
+between @code{@var{array}[@var{i}]} and @code{@var{array}[@var{i}+1]}.
 If @var{fieldsep} is a single
-space then any leading whitespace goes into @code{@var{seps}[0]} and 
+space, then any leading whitespace goes into @code{@var{seps}[0]} and
 any trailing
-whitespace goes into @code{@var{seps}[@var{n}]} where @var{n} is the 
-return value of 
-@code{split()} (that is, the number of elements in @var{array}).
+whitespace goes into @code{@var{seps}[@var{n}]}, where @var{n} is the
+return value of
+@code{split()} (i.e., the number of elements in @var{array}).
 
 The @code{split()} function splits strings into pieces in a
 manner similar to the way input lines are split into fields.  For example:
@@ -16729,7 +16974,7 @@ split("cul-de-sac", a, "-", seps)
 
 @noindent
 @cindex strings splitting, example
-splits the string @samp{cul-de-sac} into three fields using @samp{-} as the
+splits the string @code{"cul-de-sac"} into three fields using @samp{-} as the
 separator.  It sets the contents of the array @code{a} as follows:
 
 @example
@@ -16754,21 +16999,20 @@ As with input field-splitting, when the value of @var{fieldsep} is
 the elements of
 @var{array} but not in @var{seps}, and the elements
 are separated by runs of whitespace.
-Also as with input field-splitting, if @var{fieldsep} is the null string, each
+Also, as with input field splitting, if @var{fieldsep} is the null string, each
 individual character in the string is split into its own array element.
 @value{COMMONEXT}
 
 Note, however, that @code{RS} has no effect on the way @code{split()}
-works. Even though @samp{RS = ""} causes newline to also be an input
+works. Even though @samp{RS = ""} causes the newline character to also be an input
 field separator, this does not affect how @code{split()} splits strings.
 
 @cindex dark corner, @code{split()} function
 Modern implementations of @command{awk}, including @command{gawk}, allow
-the third argument to be a regexp constant (@code{/abc/}) as well as a
-string.
-@value{DARKCORNER}
+the third argument to be a regexp constant (@w{@code{/}@dots{}@code{/}})
+as well as a string.  @value{DARKCORNER}
 The POSIX standard allows this as well.
-@xref{Computed Regexps}, for a
+@DBXREF{Computed Regexps} for a
 discussion of the difference between using a string constant or a regexp constant,
 and the implications for writing your program correctly.
 
@@ -16819,7 +17063,7 @@ Using the @code{strtonum()} function is @emph{not} the same as adding zero
 to a string value; the automatic coercion of strings to numbers
 works only for decimal data, not for octal or hexadecimal.@footnote{Unless
 you use the @option{--non-decimal-data} option, which isn't recommended.
-@xref{Nondecimal Data}, for more information.}
+@DBXREF{Nondecimal Data} for more information.}
 
 Note also that @code{strtonum()} uses the current locale's decimal point
 for recognizing numbers (@pxref{Locales}).
@@ -16837,7 +17081,7 @@ Return the number of substitutions made (zero or one).
 The @var{regexp} argument may be either a regexp constant
 (@code{/}@dots{}@code{/}) or a string constant (@code{"}@dots{}@code{"}).
 In the latter case, the string is treated as a regexp to be matched.
-@xref{Computed Regexps}, for a
+@DBXREF{Computed Regexps} for a
 discussion of the difference between the two forms, and the
 implications for writing your program correctly.
 
@@ -16903,7 +17147,7 @@ an @samp{&}:
 @cindex @code{sub()} function, arguments of
 @cindex @code{gsub()} function, arguments of
 As mentioned, the third argument to @code{sub()} must
-be a variable, field or array element.
+be a variable, field, or array element.
 Some versions of @command{awk} allow the third argument to
 be an expression that is not an lvalue.  In such a case, @code{sub()}
 still searches for the pattern and returns zero or one, but the result of
@@ -17023,7 +17267,7 @@ Although this makes a certain amount of sense, it can be surprising.
 
 
 @node Gory Details
-@subsubsection More About @samp{\} and @samp{&} with @code{sub()}, @code{gsub()}, and @code{gensub()}
+@subsubsection More about @samp{\} and @samp{&} with @code{sub()}, @code{gsub()}, and @code{gensub()}
 
 @cindex escape processing, @code{gsub()}/@code{gensub()}/@code{sub()} functions
 @cindex @code{sub()} function, escape processing
@@ -17062,15 +17306,15 @@ example, @code{"a\qb"} is treated as @code{"aqb"}.
 
 At the runtime level, the various functions handle sequences of
 @samp{\} and @samp{&} differently.  The situation is (sadly) somewhat complex.
-Historically, the @code{sub()} and @code{gsub()} functions treated the two
-character sequence @samp{\&} specially; this sequence was replaced in
+Historically, the @code{sub()} and @code{gsub()} functions treated the
+two-character sequence @samp{\&} specially; this sequence was replaced in
 the generated text with a single @samp{&}.  Any other @samp{\} within
 the @var{replacement} string that did not precede an @samp{&} was passed
 through unchanged.  This is illustrated in @ref{table-sub-escapes}.
 
 @c Thank to Karl Berry for help with the TeX stuff.
 @float Table,table-sub-escapes
-@caption{Historical Escape Sequence Processing for @code{sub()} and @code{gsub()}}
+@caption{Historical escape sequence processing for @code{sub()} and @code{gsub()}}
 @tex
 \vbox{\bigskip
 % We need more characters for escape and tab ...
@@ -17121,7 +17365,7 @@ _bigskip}
 @end float
 
 @noindent
-This table shows both the lexical-level processing, where
+This table shows the lexical-level processing, where
 an odd number of backslashes becomes an even number at the runtime level,
 as well as the runtime processing done by @code{sub()}.
 (For the sake of simplicity, the rest of the following tables only show the
@@ -17142,7 +17386,7 @@ This is shown in
 @ref{table-sub-proposed}.
 
 @float Table,table-sub-proposed
-@caption{GNU @command{awk} Rules For @code{sub()} And Backslash}
+@caption{@command{gawk} rules for @code{sub()} and backslash}
 @tex
 \vbox{\bigskip
 % We need more characters for escape and tab ...
@@ -17187,7 +17431,7 @@ _bigskip}
 @end float
 
 In a nutshell, at the runtime level, there are now three special sequences
-of characters (@samp{\\\&}, @samp{\\&} and @samp{\&}) whereas historically
+of characters (@samp{\\\&}, @samp{\\&}, and @samp{\&}) whereas historically
 there was only one.  However, as in the historical case, any @samp{\} that
 is not part of one of these three sequences is not special and appears
 in the output literally.
@@ -17205,7 +17449,7 @@ by anything else is not special; the @samp{\} is placed straight into the output
 These rules are presented in @ref{table-posix-sub}.
 
 @float Table,table-posix-sub
-@caption{POSIX Rules For @code{sub()} And @code{gsub()}}
+@caption{POSIX rules for @code{sub()} and @code{gsub()}}
 @tex
 \vbox{\bigskip
 % We need more characters for escape and tab ...
@@ -17253,13 +17497,13 @@ The only case where the difference is noticeable is the last one: @samp{\\\\}
 is seen as @samp{\\} and produces @samp{\} instead of @samp{\\}.
 
 Starting with @value{PVERSION} 3.1.4, @command{gawk} followed the POSIX rules
-when @option{--posix} is specified (@pxref{Options}). Otherwise,
-it continued to follow the proposed rules, since
+when @option{--posix} was specified (@pxref{Options}). Otherwise,
+it continued to follow the proposed rules, as
 that had been its behavior for many years.
 
 When @value{PVERSION} 4.0.0 was released, the @command{gawk} maintainer
 made the POSIX rules the default, breaking well over a decade's worth
-of backwards compatibility.@footnote{This was rather naive of him, despite
+of backward compatibility.@footnote{This was rather naive of him, despite
 there being a note in this section indicating that the next major version
 would move to the POSIX rules.} Needless to say, this was a bad idea,
 and as of @value{PVERSION} 4.0.1, @command{gawk} resumed its historical
@@ -17274,7 +17518,7 @@ appears in the generated text and the @samp{\} does not,
 as shown in @ref{table-gensub-escapes}.
 
 @float Table,table-gensub-escapes
-@caption{Escape Sequence Processing For @code{gensub()}}
+@caption{Escape sequence processing for @code{gensub()}}
 @tex
 \vbox{\bigskip
 % We need more characters for escape and tab ...
@@ -17321,7 +17565,7 @@ _bigskip}
 @end ifnottex
 @end float
 
-Because of the complexity of the lexical and runtime level processing
+Because of the complexity of the lexical- and runtime-level processing
 and the special cases for @code{sub()} and @code{gsub()},
 we recommend the use of @command{gawk} and @code{gensub()} when you have
 to do substitutions.
@@ -17341,12 +17585,13 @@ Optional parameters are enclosed in square brackets ([ ]):
 Close the file @var{filename} for input or output. Alternatively, the
 argument may be a shell command that was used for creating a coprocess, or
 for redirecting to or from a pipe; then the coprocess or pipe is closed.
-@xref{Close Files And Pipes},
+@DBXREF{Close Files And Pipes}
 for more information.
 
 When closing a coprocess, it is occasionally useful to first close
 one end of the two-way pipe and then to close the other.  This is done
 by providing a second argument to @code{close()}.  This second argument
+(@var{how})
 should be one of the two string values @code{"to"} or @code{"from"},
 indicating which end of the pipe to close.  Case in the string does
 not matter.
@@ -17365,25 +17610,25 @@ a pipe or coprocess.
 
 @cindex buffers, flushing
 @cindex output, buffering
-Many utility programs @dfn{buffer} their output; i.e., they save information
+Many utility programs @dfn{buffer} their output (i.e., they save information
 to write to a disk file or the screen in memory until there is enough
-for it to be worthwhile to send the data to the output device.
+for it to be worthwhile to send the data to the output device).
 This is often more efficient than writing
 every little bit of information as soon as it is ready.  However, sometimes
-it is necessary to force a program to @dfn{flush} its buffers; that is,
-write the information to its destination, even if a buffer is not full.
+it is necessary to force a program to @dfn{flush} its buffers (i.e.,
+write the information to its destination, even if a buffer is not full).
 This is the purpose of the @code{fflush()} function---@command{gawk} also
-buffers its output and the @code{fflush()} function forces
+buffers its output, and the @code{fflush()} function forces
 @command{gawk} to flush its buffers.
 
 @cindex extensions, common@comma{} @code{fflush()} function
 @cindex Brian Kernighan's @command{awk}
 Brian Kernighan added @code{fflush()} to his @command{awk} in April
-of 1992.  For two decades, it was a common extension.  In December,
+1992.  For two decades, it was a common extension.  In December
 2012, it was accepted for inclusion into the POSIX standard.
 See @uref{http://austingroupbugs.net/view.php?id=634, the Austin Group website}.
 
-POSIX standardizes @code{fflush()} as follows: If there
+POSIX standardizes @code{fflush()} as follows: if there
 is no argument, or if the argument is the null string (@w{@code{""}}),
 then @command{awk} flushes the buffers for @emph{all} open output files
 and pipes.
@@ -17394,7 +17639,7 @@ would flush only the standard output if there was no argument,
 and flush all output files and pipes if the argument was the null
 string. This was changed in order to be compatible with Brian
 Kernighan's @command{awk}, in the hope that standardizing this
-feature in POSIX would then be easier (which indeed helped).
+feature in POSIX would then be easier (which indeed proved to be the case).
 
 With @command{gawk},
 you can use @samp{fflush("/dev/stdout")} if you wish to flush
@@ -17405,7 +17650,7 @@ only the standard output.
 @c @cindex warnings, automatic
 @cindex troubleshooting, @code{fflush()} function
 @code{fflush()} returns zero if the buffer is successfully flushed;
-otherwise, it returns non-zero. (@command{gawk} returns @minus{}1.)
+otherwise, it returns a nonzero value. (@command{gawk} returns @minus{}1.)
 In the case where all buffers are flushed, the return value is zero
 only if all buffers were flushed successfully.  Otherwise, it is
 @minus{}1, and @command{gawk} warns about the problem @var{filename}.
@@ -17415,11 +17660,54 @@ a file or pipe that was opened for reading (such as with @code{getline}),
 or if @var{filename} is not an open file, pipe, or coprocess.
 In such a case, @code{fflush()} returns @minus{}1, as well.
 
+@sidebar Interactive Versus Noninteractive Buffering
+@cindex buffering, interactive vs.@: noninteractive
+
+As a side point, buffering issues can be even more confusing if
+your program is @dfn{interactive} (i.e., communicating
+with a user sitting at a keyboard).@footnote{A program is interactive
+if the standard output is connected to a terminal device. On modern
+systems, this means your keyboard and screen.}
+
+@c Thanks to Walter.Mecky@dresdnerbank.de for this example, and for
+@c motivating me to write this section.
+Interactive programs generally @dfn{line buffer} their output (i.e., they
+write out every line).  Noninteractive programs wait until they have
+a full buffer, which may be many lines of output.
+Here is an example of the difference:
+
+@example
+$ @kbd{awk '@{ print $1 + $2 @}'}
+@kbd{1 1}
+@print{} 2
+@kbd{2 3}
+@print{} 5
+@kbd{Ctrl-d}
+@end example
+
+@noindent
+Each line of output is printed immediately. Compare that behavior
+with this example:
+
+@example
+$ @kbd{awk '@{ print $1 + $2 @}' | cat}
+@kbd{1 1}
+@kbd{2 3}
+@kbd{Ctrl-d}
+@print{} 2
+@print{} 5
+@end example
+
+@noindent
+Here, no output is printed until after the @kbd{Ctrl-d} is typed, because
+it is all buffered and sent down the pipe to @command{cat} in one shot.
+@end sidebar
+
 @item @code{system(@var{command})}
 @cindexawkfunc{system}
 @cindex invoke shell command
 @cindex interacting with other programs
-Execute the operating-system
+Execute the operating system
 command @var{command} and then return to the @command{awk} program.
 Return @var{command}'s exit status.
 
@@ -17462,49 +17750,6 @@ When @option{--sandbox} is specified, the @code{system()} function is disabled
 
 @end table
 
-@sidebar Interactive Versus Noninteractive Buffering
-@cindex buffering, interactive vs.@: noninteractive
-
-As a side point, buffering issues can be even more confusing, depending
-upon whether your program is @dfn{interactive}, i.e., communicating
-with a user sitting at a keyboard.@footnote{A program is interactive
-if the standard output is connected to a terminal device. On modern
-systems, this means your keyboard and screen.}
-
-@c Thanks to Walter.Mecky@dresdnerbank.de for this example, and for
-@c motivating me to write this section.
-Interactive programs generally @dfn{line buffer} their output; i.e., they
-write out every line.  Noninteractive programs wait until they have
-a full buffer, which may be many lines of output.
-Here is an example of the difference:
-
-@example
-$ @kbd{awk '@{ print $1 + $2 @}'}
-@kbd{1 1}
-@print{} 2
-@kbd{2 3}
-@print{} 5
-@kbd{Ctrl-d}
-@end example
-
-@noindent
-Each line of output is printed immediately. Compare that behavior
-with this example:
-
-@example
-$ @kbd{awk '@{ print $1 + $2 @}' | cat}
-@kbd{1 1}
-@kbd{2 3}
-@kbd{Ctrl-d}
-@print{} 2
-@print{} 5
-@end example
-
-@noindent
-Here, no output is printed until after the @kbd{Ctrl-d} is typed, because
-it is all buffered and sent down the pipe to @command{cat} in one shot.
-@end sidebar
-
 @sidebar Controlling Output Buffering with @code{system()}
 @cindex buffers, flushing
 @cindex buffering, input/output
@@ -17523,7 +17768,7 @@ system("")   # flush output
 @command{gawk} treats this use of the @code{system()} function as a special
 case and is smart enough not to run a shell (or other command
 interpreter) with the empty command.  Therefore, with @command{gawk}, this
-idiom is not only useful, it is also efficient.  While this method should work
+idiom is not only useful, it is also efficient.  Although this method should work
 with other @command{awk} implementations, it does not necessarily avoid
 starting an unnecessary shell.  (Other implementations may only
 flush the buffer associated with the standard output and not necessarily
@@ -17566,18 +17811,14 @@ you would see the latter (undesirable) output.
 @subsection Time Functions
 @cindex time functions
 
-@c STARTOFRANGE tst
 @cindex timestamps
-@c STARTOFRANGE logftst
 @cindex log files, timestamps in
-@c STARTOFRANGE filogtst
 @cindex files, log@comma{} timestamps in
-@c STARTOFRANGE gawtst
 @cindex @command{gawk}, timestamps
 @cindex POSIX @command{awk}, timestamps and
-@code{awk} programs are commonly used to process log files
+@command{awk} programs are commonly used to process log files
 containing timestamp information, indicating when a
-particular log record was written.  Many programs log their timestamp
+particular log record was written.  Many programs log their timestamps
 in the form returned by the @code{time()} system call, which is the
 number of seconds since a particular epoch.  On POSIX-compliant systems,
 it is the number of seconds since
@@ -17604,6 +17845,7 @@ which is sufficient to represent times through
 2038-01-19 03:14:07 UTC.  Many systems support a wider range of timestamps,
 including negative timestamps that represent times before the
 epoch.
+@c FIXME: Use @sup here for superscript
 
 @cindex @command{date} utility, GNU
 @cindex time, retrieving
@@ -17638,7 +17880,7 @@ The values of these numbers need not be within the ranges specified;
 for example, an hour of @minus{}1 means 1 hour before midnight.
 The origin-zero Gregorian calendar is assumed, with year 0 preceding
 year 1 and year @minus{}1 preceding year 0.
-The time is assumed to be in the local timezone.
+The time is assumed to be in the local time zone.
 If the daylight-savings flag is positive, the time is assumed to be
 daylight savings time; if zero, the time is assumed to be standard
 time; and if negative (the default), @code{mktime()} attempts to determine
@@ -17650,7 +17892,6 @@ is out of range, @code{mktime()} returns @minus{}1.
 @cindex @command{gawk}, @code{PROCINFO} array in
 @cindex @code{PROCINFO} array
 @item @code{strftime(}[@var{format} [@code{,} @var{timestamp} [@code{,} @var{utc-flag}] ] ]@code{)}
-@c STARTOFRANGE strf
 @cindexgawkfunc{strftime}
 @cindex format time string
 Format the time specified by @var{timestamp}
@@ -17662,14 +17903,14 @@ Mean Time). Otherwise, the value is formatted for the local time zone.
 The @var{timestamp} is in the same format as the value returned by the
 @code{systime()} function.  If no @var{timestamp} argument is supplied,
 @command{gawk} uses the current time of day as the timestamp.
-If no @var{format} argument is supplied, @code{strftime()} uses
+Without a @var{format} argument, @code{strftime()} uses
 the value of @code{PROCINFO["strftime"]} as the format string
 (@pxref{Built-in Variables}).
 The default string value is
 @code{@w{"%a %b %e %H:%M:%S %Z %Y"}}.  This format string produces
 output that is equivalent to that of the @command{date} utility.
 You can assign a new value to @code{PROCINFO["strftime"]} to
-change the default format; see below for the various format directives.
+change the default format; see the following list for the various format directives.
 
 @item @code{systime()}
 @cindexgawkfunc{systime}
@@ -17746,16 +17987,16 @@ This is the ISO 8601 date format.
 
 @item %g
 The year modulo 100 of the ISO 8601 week number, as a decimal number (00--99).
-For example, January 1, 2012 is in week 53 of 2011. Thus, the year
+For example, January 1, 2012, is in week 53 of 2011. Thus, the year
 of its ISO 8601 week number is 2011, even though its year is 2012.
-Similarly, December 31, 2012 is in week 1 of 2013. Thus, the year
+Similarly, December 31, 2012, is in week 1 of 2013. Thus, the year
 of its ISO week number is 2013, even though its year is 2012.
 
 @item %G
 The full year of the ISO week number, as a decimal number.
 
 @item %h
-Equivalent to @code{%b}.
+Equivalent to @samp{%b}.
 
 @item %H
 The hour (24-hour clock) as a decimal number (00--23).
@@ -17799,12 +18040,12 @@ Equivalent to specifying @samp{%H:%M:%S}.
 The weekday as a decimal number (1--7).  Monday is day one.
 
 @item %U
-The week number of the year (the first Sunday as the first day of week one)
+The week number of the year (with the first Sunday as the first day of week one)
 as a decimal number (00--53).
 
 @c @cindex ISO 8601
 @item %V
-The week number of the year (the first Monday as the first
+The week number of the year (with the first Monday as the first
 day of week one) as a decimal number (01--53).
 The method for determining the week number is as specified by ISO 8601.
 (To wit: if the week containing January 1 has four or more days in the
@@ -17815,7 +18056,7 @@ and the next week is week one.)
 The weekday as a decimal number (0--6).  Sunday is day zero.
 
 @item %W
-The week number of the year (the first Monday as the first day of week one)
+The week number of the year (with the first Monday as the first day of week one)
 as a decimal number (00--53).
 
 @item %x
@@ -17824,7 +18065,7 @@ The locale's ``appropriate'' date representation.
 
 @item %X
 The locale's ``appropriate'' time representation.
-(This is @code{%T} in the @code{"C"} locale.)
+(This is @samp{%T} in the @code{"C"} locale.)
 
 @item %y
 The year modulo 100 as a decimal number (00--99).
@@ -17835,8 +18076,8 @@ The full year as a decimal number (e.g., 2015).
 @c @cindex RFC 822
 @c @cindex RFC 1036
 @item %z
-The timezone offset in a +HHMM format (e.g., the format necessary to
-produce RFC 822/RFC 1036 date headers).
+The time zone offset in a @samp{+@var{HHMM}} format (e.g., the format
+necessary to produce RFC 822/RFC 1036 date headers).
 
 @item %Z
 The time zone name or abbreviation; no characters if
@@ -17844,8 +18085,8 @@ no time zone is determinable.
 
 @item %Ec %EC %Ex %EX %Ey %EY %Od %Oe %OH
 @itemx %OI %Om %OM %OS %Ou %OU %OV %Ow %OW %Oy
-``Alternate representations'' for the specifications
-that use only the second letter (@code{%c}, @code{%C},
+``Alternative representations'' for the specifications
+that use only the second letter (@samp{%c}, @samp{%C},
 and so on).@footnote{If you don't understand any of this, don't worry about
 it; these facilities are meant to make it easier to ``internationalize''
 programs.
@@ -17857,7 +18098,7 @@ Other internationalization features are described in
 A literal @samp{%}.
 @end table
 
-If a conversion specifier is not one of the above, the behavior is
+If a conversion specifier is not one of those just listed, the behavior is
 undefined.@footnote{This is because ISO C leaves the
 behavior of the C version of @code{strftime()} undefined and @command{gawk}
 uses the system's version of @code{strftime()} if it's there.
@@ -17884,11 +18125,11 @@ Single-digit numbers are padded with a space.
 @ignore
 @item %N
 The ``Emperor/Era'' name.
-Equivalent to @code{%C}.
+Equivalent to @samp{%C}.
 
 @item %o
 The ``Emperor/Era'' year.
-Equivalent to @code{%y}.
+Equivalent to @samp{%y}.
 @end ignore
 
 @item %s
@@ -17899,9 +18140,8 @@ The time as a decimal timestamp in seconds since the epoch.
 The date in VMS format (e.g., @samp{20-JUN-1991}).
 @end ignore
 @end table
-@c ENDOFRANGE strf
 
-Additionally, the alternate representations are recognized but their
+Additionally, the alternative representations are recognized but their
 normal representations are used.
 
 @cindex @code{date} utility, POSIX
@@ -17915,7 +18155,7 @@ interprets the current time according to the format specifiers in
 the string.  For example:
 
 @example
-$ date '+Today is %A, %B %d, %Y.'
+$ @kbd{date '+Today is %A, %B %d, %Y.'}
 @print{} Today is Monday, September 22, 2014.
 @end example
 
@@ -17950,23 +18190,14 @@ gawk 'BEGIN  @{
     exit exitval
 @}' "$@@"
 @end example
-@c ENDOFRANGE tst
-@c ENDOFRANGE logftst
-@c ENDOFRANGE filogtst
-@c ENDOFRANGE gawtst
 
 @node Bitwise Functions
 @subsection Bit-Manipulation Functions
 @cindex bit-manipulation functions
-@c STARTOFRANGE bit
 @cindex bitwise, operations
-@c STARTOFRANGE and
 @cindex AND bitwise operation
-@c STARTOFRANGE oro
 @cindex OR bitwise operation
-@c STARTOFRANGE xor
 @cindex XOR bitwise operation
-@c STARTOFRANGE opbit
 @cindex operations, bitwise
 @quotation
 @i{I can explain it for you, but I can't understand it for you.}
@@ -17979,12 +18210,14 @@ each successive pair of bits in the operands.
 Three common operations are bitwise AND, OR, and XOR.
 The operations are described in @ref{table-bitwise-ops}.
 
+@c 11/2014: Postprocessing turns the docbook informaltable
+@c into a table. Hurray for scripting!
 @float Table,table-bitwise-ops
-@caption{Bitwise Operations}
+@caption{Bitwise operations}
 @ifnottex
 @ifnotdocbook
 @display
-                Bit Operator
+                Bit operator
           |  AND  |   OR  |  XOR
           |---+---+---+---+---+---
 Operands  | 0 | 1 | 0 | 1 | 0 | 1
@@ -18042,7 +18275,7 @@ Operands  | 0 | 1 | 0 | 1 | 0 | 1
 <tbody>
 <row>
 <entry colsep="0"></entry>
-<entry spanname="optitle"><emphasis role="bold">Bit Operator</emphasis></entry>
+<entry spanname="optitle"><emphasis role="bold">Bit operator</emphasis></entry>
 </row>
 
 <row rowsep="1">
@@ -18106,10 +18339,9 @@ of a given value.
 Finally, two other common operations are to shift the bits left or right.
 For example, if you have a bit string @samp{10111001} and you shift it
 right by three bits, you end up with @samp{00010111}.@footnote{This example
-shows that 0's come in on the left side. For @command{gawk}, this is
+shows that zeros come in on the left side. For @command{gawk}, this is
 always true, but in some languages, it's possible to have the left side
-fill with 1's.}
-@c Purposely decided to use   0's   and   1's   here.  2/2001.
+fill with ones.}
 If you start over again with @samp{10111001} and shift it left by three
 bits, you end up with @samp{11001000}.  The following list describes
 @command{gawk}'s built-in functions that implement the bitwise operations.
@@ -18148,7 +18380,7 @@ Return the value of @var{val}, shifted right by @var{count} bits.
 Return the bitwise XOR of the arguments. There must be at least two.
 @end table
 
-For all of these functions, first the double precision floating-point value is
+For all of these functions, first the double-precision floating-point value is
 converted to the widest C unsigned integer type, then the bitwise operation is
 performed.  If the result cannot be represented exactly as a C @code{double},
 leading nonzero bits are removed one by one until it can be represented
@@ -18163,7 +18395,7 @@ that illustrates the use of these functions:
 @example
 @group
 @c file eg/lib/bits2str.awk
-# bits2str --- turn a byte into readable 1's and 0's
+# bits2str --- turn a byte into readable ones and zeros
 
 function bits2str(bits,        data, mask)
 @{
@@ -18237,17 +18469,18 @@ $ @kbd{gawk -f testbits.awk}
 @cindex converting, numbers to strings
 @cindex number as string of bits
 The @code{bits2str()} function turns a binary number into a string.
-The number @code{1} represents a binary value where the rightmost bit
-is set to 1.  Using this mask,
+Initializing @code{mask} to one creates
+a binary value where the rightmost bit
+is set to one.  Using this mask,
 the function repeatedly checks the rightmost bit.
 ANDing the mask with the value indicates whether the
-rightmost bit is 1 or not. If so, a @code{"1"} is concatenated onto the front
+rightmost bit is one or not. If so, a @code{"1"} is concatenated onto the front
 of the string.
 Otherwise, a @code{"0"} is added.
 The value is then shifted right by one bit and the loop continues
-until there are no more 1 bits.
+until there are no more one bits.
 
-If the initial value is zero it returns a simple @code{"0"}.
+If the initial value is zero, it returns a simple @code{"0"}.
 Otherwise, at the end, it pads the value with zeros to represent multiples
 of 8-bit quantities. This is typical in modern computers.
 
@@ -18256,11 +18489,6 @@ decimal and octal values for the same numbers
 (@pxref{Nondecimal-numbers}),
 and then demonstrates the
 results of the @code{compl()}, @code{lshift()}, and @code{rshift()} functions.
-@c ENDOFRANGE bit
-@c ENDOFRANGE and
-@c ENDOFRANGE oro
-@c ENDOFRANGE xor
-@c ENDOFRANGE opbit
 
 @node Type Functions
 @subsection Getting Type Information
@@ -18274,7 +18502,7 @@ that traverses every element of an array of arrays
 @cindexgawkfunc{isarray}
 @cindex scalar or array
 @item isarray(@var{x})
-Return a true value if @var{x} is an array. Otherwise return false.
+Return a true value if @var{x} is an array. Otherwise, return false.
 @end table
 
 @code{isarray()} is meant for use in two circumstances. The first is when
@@ -18284,8 +18512,8 @@ an array or not.  The second is inside the body of a user-defined function
 array or not.
 
 @quotation NOTE
-Using @code{isarray()} at the global level to test 
-variables makes no sense. Since you are the one writing the program, you
+Using @code{isarray()} at the global level to test
+variables makes no sense. Because you are the one writing the program, you
 are supposed to know if your variables are arrays or not. And in fact,
 due to the way @command{gawk} works, if you pass the name of a variable
 that has not been previously used to @code{isarray()}, @command{gawk}
@@ -18335,25 +18563,21 @@ The default value for @var{category} is @code{"LC_MESSAGES"}.
 Return the plural form used for @var{number} of the
 translation of @var{string1} and @var{string2} in text domain
 @var{domain} for locale category @var{category}. @var{string1} is the
-English singular variant of a message, and @var{string2} the English plural
+English singular variant of a message, and @var{string2} is the English plural
 variant of the same message.
 The default value for @var{domain} is the current value of @code{TEXTDOMAIN}.
 The default value for @var{category} is @code{"LC_MESSAGES"}.
 @end table
-@c ENDOFRANGE funcbi
-@c ENDOFRANGE bifunc
 
 @node User-defined
 @section User-Defined Functions
 
-@c STARTOFRANGE udfunc
 @cindex user-defined functions
-@c STARTOFRANGE funcud
 @cindex functions, user-defined
 Complicated @command{awk} programs can often be simplified by defining
 your own functions.  User-defined functions can be called just like
 built-in ones (@pxref{Function Calls}), but it is up to you to define
-them, i.e., to tell @command{awk} what they should do.
+them (i.e., to tell @command{awk} what they should do).
 
 @menu
 * Definition Syntax::           How to write definitions and what they mean.
@@ -18368,12 +18592,11 @@ them, i.e., to tell @command{awk} what they should do.
 @subsection Function Definition Syntax
 
 @quotation
-@i{It's entirely fair to say that the @command{awk} syntax for local
+@i{It's entirely fair to say that the awk syntax for local
 variable definitions is appallingly awful.}
 @author Brian Kernighan
 @end quotation
 
-@c STARTOFRANGE fdef
 @cindex functions, defining
 Definitions of functions can appear anywhere between the rules of an
 @command{awk} program.  Thus, the general form of an @command{awk} program is
@@ -18411,14 +18634,23 @@ the call.
 
 A function cannot have two parameters with the same name, nor may it
 have a parameter with the same name as the function itself.
-In addition, according to the POSIX standard, function parameters
+
+@quotation CAUTION
+According to the POSIX standard, function parameters
 cannot have the same name as one of the special predefined variables
-(@pxref{Built-in Variables}).  Not all versions of @command{awk} enforce
-this restriction.
+(@pxref{Built-in Variables}), nor may a function parameter have the
+same name as another function.
+
+Not all versions of @command{awk} enforce
+these restrictions.
+@command{gawk} always enforces the first restriction.
+With @option{--posix} (@pxref{Options}),
+it also enforces the second restriction.
+@end quotation
 
 Local variables act like the empty string if referenced where a string
 value is required, and like zero if referenced where a numeric value
-is required. This is the same as regular variables that have never been
+is required. This is the same as the behavior of regular variables that have never been
 assigned a value.  (There is more to understand about local variables;
 @pxref{Dynamic Typing}.)
 
@@ -18452,7 +18684,7 @@ During execution of the function body, the arguments and local variable
 values hide, or @dfn{shadow}, any variables of the same names used in the
 rest of the program.  The shadowed variables are not accessible in the
 function definition, because there is no way to name them while their
-names have been taken away for the local variables.  All other variables
+names have been taken away for the arguments and local variables.  All other variables
 used in the @command{awk} program can be referenced or set normally in the
 function's body.
 
@@ -18492,13 +18724,13 @@ func foo() @{ a = sqrt($1) ; print a @}
 @end example
 
 @noindent
-Instead it defines a rule that, for each record, concatenates the value
+Instead, it defines a rule that, for each record, concatenates the value
 of the variable @samp{func} with the return value of the function @samp{foo}.
 If the resulting string is non-null, the action is executed.
 This is probably not what is desired.  (@command{awk} accepts this input as
 syntactically valid, because functions may be used before they are defined
 in @command{awk} programs.@footnote{This program won't actually run,
-since @code{foo()} is undefined.})
+because @code{foo()} is undefined.})
 
 @cindex portability, functions@comma{} defining
 To ensure that your @command{awk} programs are portable, always use the
@@ -18519,7 +18751,7 @@ function myprint(num)
 @end example
 
 @noindent
-To illustrate, here is an @command{awk} rule that uses our @code{myprint}
+To illustrate, here is an @command{awk} rule that uses our @code{myprint()}
 function:
 
 @example
@@ -18560,16 +18792,16 @@ in an array and start over with a new list of elements
 (@pxref{Delete}).
 Instead of having
 to repeat this loop everywhere that you need to clear out
-an array, your program can just call @code{delarray}.
+an array, your program can just call @code{delarray()}.
 (This guarantees portability.  The use of @samp{delete @var{array}} to delete
 the contents of an entire array is a relatively recent@footnote{Late in 2012.}
 addition to the POSIX standard.)
 
 The following is an example of a recursive function.  It takes a string
-as an input parameter and returns the string in backwards order.
+as an input parameter and returns the string in reverse order.
 Recursive functions must always have a test that stops the recursion.
 In this case, the recursion terminates when the input string is
-already empty.
+already empty:
 
 @c 8/2014: Thanks to Mike Brennan for the improved formulation
 @cindex @code{rev()} user-defined function
@@ -18617,15 +18849,13 @@ function ctime(ts,    format)
 @end example
 
 You might think that @code{ctime()} could use @code{PROCINFO["strftime"]}
-for its format string. That would be a mistake, since @code{ctime()} is
+for its format string. That would be a mistake, because @code{ctime()} is
 supposed to return the time formatted in a standard fashion, and user-level
 code could have changed @code{PROCINFO["strftime"]}.
-@c ENDOFRANGE fdef
 
 @node Function Caveats
 @subsection Calling User-Defined Functions
 
-@c STARTOFRANGE fudc
 @cindex functions, user-defined, calling
 @dfn{Calling a function} means causing the function to run and do its job.
 A function call is an expression and its value is the value returned by
@@ -18638,7 +18868,7 @@ the function.
 @end menu
 
 @node Calling A Function
-@subsubsection Writing A Function Call
+@subsubsection Writing a Function Call
 
 A function call consists of the function name followed by the arguments
 in parentheses.  @command{awk} expressions are what you write in the
@@ -18653,7 +18883,7 @@ foo(x y, "lose", 4 * z)
 
 @quotation CAUTION
 Whitespace characters (spaces and TABs) are not allowed
-between the function name and the open-parenthesis of the argument list.
+between the function name and the opening parenthesis of the argument list.
 If you write whitespace by mistake, @command{awk} might think that you mean
 to concatenate a variable with an expression in parentheses.  However, it
 notices that you used a function name and not a variable name, and reports
@@ -18665,7 +18895,7 @@ an error.
 
 @cindex local variables, in a function
 @cindex variables, local to a function
-Unlike many languages,
+Unlike in many languages,
 there is no way to make a variable local to a @code{@{} @dots{} @code{@}} block in
 @command{awk}, but you can make a variable local to a function. It is
 good practice to do so whenever a variable is needed only in that
@@ -18674,7 +18904,7 @@ function.
 To make a variable local to a function, simply declare the variable as
 an argument after the actual function arguments
 (@pxref{Definition Syntax}).
-Look at the following example where variable
+Look at the following example, where variable
 @code{i} is a global variable used by both functions @code{foo()} and
 @code{bar()}:
 
@@ -18693,7 +18923,7 @@ function foo(j)
     print "foo's i=" i
 @}
 
-BEGIN @{ 
+BEGIN @{
       i = 10
       print "top's i=" i
       foo(0)
@@ -18715,14 +18945,14 @@ foo's i=3
 top's i=3
 @end example
 
-If you want @code{i} to be local to both @code{foo()} and @code{bar()} do as
-follows (the extra-space before @code{i} is a coding convention to
+If you want @code{i} to be local to both @code{foo()} and @code{bar()}, do as
+follows (the extra space before @code{i} is a coding convention to
 indicate that @code{i} is a local variable, not an argument):
 
 @example
 function bar(    i)
 @{
-    for (i = 0; i < 3; i++) 
+    for (i = 0; i < 3; i++)
         print "bar's i=" i
 @}
 
@@ -18734,10 +18964,10 @@ function foo(j,    i)
     print "foo's i=" i
 @}
 
-BEGIN @{ 
+BEGIN @{
       i = 10
       print "top's i=" i
-      foo(0) 
+      foo(0)
       print "top's i=" i
 @}
 @end example
@@ -18796,21 +19026,16 @@ At level 2, index 2 is found in a
 @end example
 
 @node Pass By Value/Reference
-@subsubsection Passing Function Arguments By Value Or By Reference
+@subsubsection Passing Function Arguments by Value Or by Reference
 
 In @command{awk}, when you declare a function, there is no way to
 declare explicitly whether the arguments are passed @dfn{by value} or
 @dfn{by reference}.
 
-Instead the passing convention is determined at runtime when
-the function is called according to the following rule:
-
-@itemize
-@item
-If the argument is an array variable, then it is passed by reference,
-@item
-Otherwise the argument is passed by value.
-@end itemize
+Instead, the passing convention is determined at runtime when
+the function is called, according to the following rule:
+if the argument is an array variable, then it is passed by reference.
+Otherwise, the argument is passed by value.
 
 @cindex call by value
 Passing an argument by value means that when a function is called, it
@@ -18885,7 +19110,7 @@ prints @samp{a[1] = 1, a[2] = two, a[3] = 3}, because
 @cindex undefined functions
 @cindex functions, undefined
 Some @command{awk} implementations allow you to call a function that
-has not been defined. They only report a problem at runtime when the
+has not been defined. They only report a problem at runtime, when the
 program actually tries to call the function. For example:
 
 @example
@@ -18913,10 +19138,15 @@ If @option{--lint} is specified
 Some @command{awk} implementations generate a runtime
 error if you use either the @code{next} statement
 or the @code{nextfile} statement
-(@pxref{Next Statement}, also @pxref{Nextfile Statement})
+(@pxref{Next Statement}, and
+@ifdocbook
+@ref{Nextfile Statement})
+@end ifdocbook
+@ifnotdocbook
+@pxref{Nextfile Statement})
+@end ifnotdocbook
 inside a user-defined function.
 @command{gawk} does not have this limitation.
-@c ENDOFRANGE fudc
 
 @node Return Statement
 @subsection The @code{return} Statement
@@ -18939,15 +19169,15 @@ makes the returned value undefined, and therefore, unpredictable.
 In practice, though, all versions of @command{awk} simply return the
 null string, which acts like zero if used in a numeric context.
 
-A @code{return} statement with no value expression is assumed at the end of
-every function definition.  So if control reaches the end of the function
-body, then technically, the function returns an unpredictable value.
+A @code{return} statement without an @var{expression} is assumed at the end of
+every function definition.  So, if control reaches the end of the function
+body, then technically the function returns an unpredictable value.
 In practice, it returns the empty string.  @command{awk}
 does @emph{not} warn you if you use the return value of such a function.
 
 Sometimes, you want to write a function for what it does, not for
 what it returns.  Such a function corresponds to a @code{void} function
-in C, C++ or Java, or to a @code{procedure} in Ada.  Thus, it may be appropriate to not
+in C, C++, or Java, or to a @code{procedure} in Ada.  Thus, it may be appropriate to not
 return any value; simply bear in mind that you should not be using the
 return value of such a function.
 
@@ -18969,8 +19199,8 @@ function maxelt(vec,   i, ret)
 @noindent
 You call @code{maxelt()} with one argument, which is an array name.  The local
 variables @code{i} and @code{ret} are not intended to be arguments;
-while there is nothing to stop you from passing more than one argument
-to @code{maxelt()}, the results would be strange.  The extra space before
+there is nothing to stop you from passing more than one argument
+to @code{maxelt()} but the results would be strange.  The extra space before
 @code{i} in the function parameter list indicates that @code{i} and
 @code{ret} are local variables.
 You should follow this convention when defining functions.
@@ -19044,7 +19274,6 @@ does report the second error.
 
 Usually, such things aren't a big issue, but it's worth
 being aware of them.
-@c ENDOFRANGE udfunc
 
 @node Indirect Calls
 @section Indirect Function Calls
@@ -19067,13 +19296,15 @@ function calls, you can specify the name of the function to call as a
 string variable, and then call the function.  Let's look at an example.
 
 Suppose you have a file with your test scores for the classes you
-are taking.  The first field is the class name. The following fields
+are taking, and
+you wish to get the sum and the average of
+your test scores.
+The first field is the class name. The following fields
 are the functions to call to process the data, up to a ``marker''
 field @samp{data:}.  Following the marker, to the end of the record,
 are the various numeric test scores.
 
-Here is the initial file; you wish to get the sum and the average of
-your test scores:
+Here is the initial file:
 
 @example
 @c file eg/data/class_data1
@@ -19107,8 +19338,8 @@ variable as the @emph{name} of the function to call.
 @cindex indirect function calls, @code{@@}-notation
 @cindex function calls, indirect, @code{@@}-notation for
 The syntax is similar to that of a regular function call: an identifier
-immediately followed by a left parenthesis, any arguments, and then
-a closing right parenthesis, with the addition of a leading @samp{@@}
+immediately followed by an opening parenthesis, any arguments, and then
+a closing parenthesis, with the addition of a leading @samp{@@}
 character:
 
 @example
@@ -19117,7 +19348,7 @@ result = @@the_func()   # calls the sum() function
 @end example
 
 Here is a full program that processes the previously shown data,
-using indirect function calls.
+using indirect function calls:
 
 @example
 @c file eg/prog/indirectcall.awk
@@ -19156,9 +19387,9 @@ function sum(first, last,   ret, i)
 @c endfile
 @end example
 
-These two functions expect to work on fields; thus the parameters
+These two functions expect to work on fields; thus, the parameters
 @code{first} and @code{last} indicate where in the fields to start and end.
-Otherwise they perform the expected computations and are not unusual.
+Otherwise, they perform the expected computations and are not unusual:
 
 @example
 @c file eg/prog/indirectcall.awk
@@ -19191,7 +19422,7 @@ saving it in @code{start}.
 The last part of the code loops through each function name (from @code{$2} up to
 the marker, @samp{data:}), calling the function named by the field. The indirect
 function call itself occurs as a parameter in the call to @code{printf}.
-(The @code{printf} format string uses @code{%s} as the format specifier so that we
+(The @code{printf} format string uses @samp{%s} as the format specifier so that we
 can use functions that return strings, as well as numbers. Note that the result
 from the indirect call is concatenated with the empty string, in order to force
 it to be a string value.)
@@ -19203,11 +19434,11 @@ $ @kbd{gawk -f indirectcall.awk class_data1}
 @print{} Biology 101:
 @print{}     sum: <352.8>
 @print{}     average: <88.2>
-@print{} 
+@print{}
 @print{} Chemistry 305:
 @print{}     sum: <356.4>
 @print{}     average: <89.1>
-@print{} 
+@print{}
 @print{} English 401:
 @print{}     sum: <376.1>
 @print{}     average: <94.025>
@@ -19217,8 +19448,8 @@ The ability to use indirect function calls is more powerful than you may
 think at first.  The C and C++ languages provide ``function pointers,'' which
 are a mechanism for calling a function chosen at runtime.  One of the most
 well-known uses of this ability is the C @code{qsort()} function, which sorts
-an array using the famous ``quick sort'' algorithm
-(see @uref{http://en.wikipedia.org/wiki/Quick_sort, the Wikipedia article}
+an array using the famous ``quicksort'' algorithm
+(see @uref{http://en.wikipedia.org/wiki/Quicksort, the Wikipedia article}
 for more information).  To use this function, you supply a pointer to a comparison
 function.  This mechanism allows you to sort arbitrary data in an arbitrary
 fashion.
@@ -19237,11 +19468,11 @@ We can do something similar using @command{gawk}, like this:
 # January 2009
 
 @c endfile
-
 @end ignore
 @c file eg/lib/quicksort.awk
-# quicksort --- C.A.R. Hoare's quick sort algorithm. See Wikipedia
-#               or almost any algorithms or computer science text
+
+# quicksort --- C.A.R. Hoare's quicksort algorithm. See Wikipedia
+#               or almost any algorithms or computer science text.
 @c endfile
 @ignore
 @c file eg/lib/quicksort.awk
@@ -19279,7 +19510,7 @@ function quicksort_swap(data, i, j,      temp)
 
 The @code{quicksort()} function receives the @code{data} array, the starting and ending
 indices to sort (@code{left} and @code{right}), and the name of a function that
-performs a ``less than'' comparison.  It then implements the quick sort algorithm.
+performs a ``less than'' comparison.  It then implements the quicksort algorithm.
 
 To make use of the sorting function, we return to our previous example. The
 first thing to do is write some comparison functions:
@@ -19329,7 +19560,7 @@ function do_sort(first, last, compare,      data, i, retval)
     retval = data[1]
     for (i = 2; i in data; i++)
         retval = retval " " data[i]
-    
+
     return retval
 @}
 @c endfile
@@ -19375,13 +19606,13 @@ $ @kbd{gawk -f quicksort.awk -f indirectcall.awk class_data2}
 @print{}     average: <88.2>
 @print{}     sort: <78.5 87.0 92.4 94.9>
 @print{}     rsort: <94.9 92.4 87.0 78.5>
-@print{} 
+@print{}
 @print{} Chemistry 305:
 @print{}     sum: <356.4>
 @print{}     average: <89.1>
 @print{}     sort: <75.2 88.2 94.7 98.3>
 @print{}     rsort: <98.3 94.7 88.2 75.2>
-@print{} 
+@print{}
 @print{} English 401:
 @print{}     sum: <376.1>
 @print{}     average: <94.025>
@@ -19390,76 +19621,29 @@ $ @kbd{gawk -f quicksort.awk -f indirectcall.awk class_data2}
 @end example
 
 Another example where indirect functions calls are useful can be found in
-processing arrays.  @DBREF{Walking Arrays} presented a simple function
-for ``walking'' an array of arrays.  That function simply printed the
-name and value of each scalar array element. However, it is easy to
-generalize that function, by passing in the name of a function to call
-when walking an array. The modified function looks like this:
-
-@example
-@c file eg/lib/processarray.awk
-function process_array(arr, name, process, do_arrays,   i, new_name)
-@{
-    for (i in arr) @{
-        new_name = (name "[" i "]")
-        if (isarray(arr[i])) @{
-            if (do_arrays)
-                @@process(new_name, arr[i])
-            process_array(arr[i], new_name, process, do_arrays)
-        @} else
-            @@process(new_name, arr[i])
-    @}
-@}
-@c endfile
-@end example
-
-The arguments are as follows:
-
-@table @code
-@item arr
-The array.
-
-@item name
-The name of the array (a string).
-
-@item process
-The name of the function to call.
-
-@item do_arrays
-If this is true, the function can handle elements that are subarrays.
-@end table
-
-If subarrays are to be processed, that is done before walking them further.
-
-When run with the following scaffolding, the function produces the same
-results as does the earlier @code{walk_array()} function:
-
-@example
-BEGIN @{
-    a[1] = 1
-    a[2][1] = 21
-    a[2][2] = 22
-    a[3] = 3
-    a[4][1][1] = 411
-    a[4][2] = 42
-
-    process_array(a, "a", "do_print", 0)
-@}
-
-function do_print(name, element)
-@{
-    printf "%s = %s\n", name, element
-@}
-@end example
+processing arrays. This is described in @ref{Walking Arrays}.
 
 Remember that you must supply a leading @samp{@@} in front of an indirect function call.
 
 Starting with @value{PVERSION} 4.1.2 of @command{gawk}, indirect function
 calls may also be used with built-in functions and with extension functions
-(@pxref{Dynamic Extensions}).  The only thing you cannot do is pass a regular
-expression constant to a built-in function through an indirect function
-call.@footnote{This may change in a future version; recheck the documentation that
-comes with your version of @command{gawk} to see if it has.}
+(@pxref{Dynamic Extensions}). There are some limitations when calling
+built-in functions indirectly, as follows.
+
+@itemize @value{BULLET}
+@item
+You cannot pass a regular expression constant to a built-in function
+through an indirect function call.@footnote{This may change in a future
+version; recheck the documentation that comes with your version of
+@command{gawk} to see if it has.} This applies to the @code{sub()},
+@code{gsub()}, @code{gensub()}, @code{match()}, @code{split()} and
+@code{patsplit()} functions.
+
+@item
+If calling @code{sub()} or @code{gsub()}, you may only pass two arguments,
+since those functions are unusual in that they update their third argument.
+This means that @code{$0} will be updated.
+@end itemize
 
 @command{gawk} does its best to make indirect function calls efficient.
 For example, in the following case:
@@ -19470,7 +19654,7 @@ for (i = 1; i <= n; i++)
 @end example
 
 @noindent
-@code{gawk} looks up the actual function to call only once.
+@command{gawk} looks up the actual function to call only once.
 
 @node Functions Summary
 @section Summary
@@ -19484,7 +19668,7 @@ functions.
 POSIX @command{awk} provides three kinds of built-in functions: numeric,
 string, and I/O.  @command{gawk} provides functions that sort arrays, work
 with values representing time, do bit manipulation, determine variable
-type (array vs.@: scalar), and internationalize and localize programs.
+type (array versus scalar), and internationalize and localize programs.
 @command{gawk} also provides several extensions to some of standard
 functions, typically in the form of additional arguments.
 
@@ -19537,10 +19721,9 @@ program. This is equivalent to function pointers in C and C++.
 
 @end itemize
 
-@c ENDOFRANGE funcud
 
 @ifnotinfo
-@part @value{PART2}Problem Solving With @command{awk}
+@part @value{PART2}Problem Solving with @command{awk}
 @end ifnotinfo
 
 @ifdocbook
@@ -19550,27 +19733,24 @@ It contains the following chapters:
 
 @itemize @value{BULLET}
 @item
-@ref{Library Functions}.
+@ref{Library Functions}
 
 @item
-@ref{Sample Programs}.
+@ref{Sample Programs}
 @end itemize
 @end ifdocbook
 
 @node Library Functions
 @chapter A Library of @command{awk} Functions
-@c STARTOFRANGE libf
 @cindex libraries of @command{awk} functions
-@c STARTOFRANGE flib
 @cindex functions, library
-@c STARTOFRANGE fudlib
 @cindex functions, user-defined, library of
 
 @DBREF{User-defined} describes how to write
 your own @command{awk} functions.  Writing functions is important, because
 it allows you to encapsulate algorithms and program tasks in a single
 place.  It simplifies programming, making program development more
-manageable, and making programs more readable.
+manageable and making programs more readable.
 
 @cindex Kernighan, Brian
 @cindex Plauger, P.J.@:
@@ -19614,9 +19794,9 @@ and would like to contribute them to the @command{awk} user community, see
 @cindex portability, example programs
 The programs in this @value{CHAPTER} and in
 @ref{Sample Programs},
-freely use features that are @command{gawk}-specific.
+freely use @command{gawk}-specific features.
 Rewriting these programs for different implementations of @command{awk}
-is pretty straightforward.
+is pretty straightforward:
 
 @itemize @value{BULLET}
 @item
@@ -19686,7 +19866,7 @@ Library functions often need to have global variables that they can use to
 preserve state information between calls to the function---for example,
 @code{getopt()}'s variable @code{_opti}
 (@pxref{Getopt Function}).
-Such variables are called @dfn{private}, since the only functions that need to
+Such variables are called @dfn{private}, as the only functions that need to
 use them are the ones in the library.
 
 When writing a library function, you should try to choose names for your
@@ -19699,7 +19879,7 @@ often use variable names like these for their own purposes.
 The example programs shown in this @value{CHAPTER} all start the names of their
 private variables with an underscore (@samp{_}).  Users generally don't use
 leading underscores in their variable names, so this convention immediately
-decreases the chances that the variable name will be accidentally shared
+decreases the chances that the variable names will be accidentally shared
 with the user's program.
 
 @cindex @code{_} (underscore), in names of private variables
@@ -19708,17 +19888,17 @@ In addition, several of the library functions use a prefix that helps
 indicate what function or set of functions use the variables---for example,
 @code{_pw_byname()} in the user database routines
 (@pxref{Passwd Functions}).
-This convention is recommended, since it even further decreases the
+This convention is recommended, as it even further decreases the
 chance of inadvertent conflict among variable names.  Note that this
 convention is used equally well for variable names and for private
-function names.@footnote{While all the library routines could have
+function names.@footnote{Although all the library routines could have
 been rewritten to use this convention, this was not done, in order to
 show how our own @command{awk} programming style has evolved and to
 provide some basis for this discussion.}
 
 As a final note on variable naming, if a function makes global variables
-available for use by a main program, it is a good convention to start that
-variable's name with a capital letter---for
+available for use by a main program, it is a good convention to start those
+variables' names with a capital letter---for
 example, @code{getopt()}'s @code{Opterr} and @code{Optind} variables
 (@pxref{Getopt Function}).
 The leading capital letter indicates that it is global, while the fact that
@@ -19729,7 +19909,7 @@ not one of @command{awk}'s predefined variables, such as @code{FS}.
 It is also important that @emph{all} variables in library
 functions that do not need to save state are, in fact, declared
 local.@footnote{@command{gawk}'s @option{--dump-variables} command-line
-option is useful for verifying this.} If this is not done, the variable
+option is useful for verifying this.} If this is not done, the variables
 could accidentally be used in the user's program, leading to bugs that
 are very difficult to track down:
 
@@ -19784,7 +19964,7 @@ programming use.
 @end menu
 
 @node Strtonum Function
-@subsection Converting Strings To Numbers
+@subsection Converting Strings to Numbers
 
 The @code{strtonum()} function (@pxref{String Functions})
 is a @command{gawk} extension.  The following function
@@ -19852,7 +20032,7 @@ function mystrtonum(str,        ret, n, i, k, c)
 #     a[6] = "1.e3"
 #     a[7] = "1.32"
 #     a[8] = "1.32E2"
-# 
+#
 #     for (i = 1; i in a; i++)
 #         print a[i], strtonum(a[i]), mystrtonum(a[i])
 # @}
@@ -19866,7 +20046,7 @@ string.  It sets @code{k} to the index in @code{"1234567"} of the current
 octal digit.
 The return value will either be the same number as the digit, or zero
 if the character is not there, which will be true for a @samp{0}.
-This is safe, since the regexp test in the @code{if} ensures that
+This is safe, because the regexp test in the @code{if} ensures that
 only octal values are converted.
 
 Similar logic applies to the code that checks for and converts a
@@ -19886,13 +20066,9 @@ be tested with @command{gawk} and the results compared to the built-in
 @node Assert Function
 @subsection Assertions
 
-@c STARTOFRANGE asse
 @cindex assertions
-@c STARTOFRANGE assef
 @cindex @code{assert()} function (C library)
-@c STARTOFRANGE libfass
 @cindex libraries of @command{awk} functions, assertions
-@c STARTOFRANGE flibass
 @cindex functions, library, assertions
 @cindex @command{awk} programs, lengthy, assertions
 When writing large programs, it is often useful to know
@@ -19931,7 +20107,7 @@ Following is the function:
 
 @example
 @c file eg/lib/assert.awk
-# assert --- assert that a condition is true. Otherwise exit.
+# assert --- assert that a condition is true. Otherwise, exit.
 
 @c endfile
 @ignore
@@ -19967,7 +20143,7 @@ is false, it prints a message to standard error, using the @code{string}
 parameter to describe the failed condition.  It then sets the variable
 @code{_assert_exit} to one and executes the @code{exit} statement.
 The @code{exit} statement jumps to the @code{END} rule. If the @code{END}
-rules finds @code{_assert_exit} to be true, it exits immediately.
+rule finds @code{_assert_exit} to be true, it exits immediately.
 
 The purpose of the test in the @code{END} rule is to
 keep any other @code{END} rules from running.  When an assertion fails, the
@@ -20008,10 +20184,6 @@ most likely causing the program to hang as it waits for input.
 There is a simple workaround to this:
 make sure that such a @code{BEGIN} rule always ends
 with an @code{exit} statement.
-@c ENDOFRANGE asse
-@c ENDOFRANGE assef
-@c ENDOFRANGE flibass
-@c ENDOFRANGE libfass
 
 @node Round Function
 @subsection Rounding Numbers
@@ -20213,7 +20385,7 @@ is always 1.  This means that on those systems, characters
 have numeric values from 128 to 255.
 Finally, large mainframe systems use the EBCDIC character set, which
 uses all 256 values.
-While there are other character sets in use on some older systems,
+There are other character sets in use on some older systems, but
 they are not really worth worrying about:
 
 @example
@@ -20263,11 +20435,11 @@ all the strings in an array into one long string.  The following function,
 the application programs
 (@pxref{Sample Programs}).
 
-Good function design is important; this function needs to be general but it
+Good function design is important; this function needs to be general, but it
 should also have a reasonable default behavior.  It is called with an array
 as well as the beginning and ending indices of the elements in the array to be
 merged.  This assumes that the array indices are numeric---a reasonable
-assumption since the array was likely created with @code{split()}
+assumption, as the array was likely created with @code{split()}
 (@pxref{String Functions}):
 
 @cindex @code{join()} user-defined function
@@ -20320,7 +20492,7 @@ more difficult than they really need to be.}
 The @code{systime()} and @code{strftime()} functions described in
 @DBREF{Time Functions}
 provide the minimum functionality necessary for dealing with the time of day
-in human readable form.  While @code{strftime()} is extensive, the control
+in human-readable form.  Although @code{strftime()} is extensive, the control
 formats are not necessarily easy to remember or intuitively obvious when
 reading a program.
 
@@ -20411,7 +20583,7 @@ allowed the user to supply an optional timestamp value to use instead
 of the current time.
 
 @node Readfile Function
-@subsection Reading A Whole File At Once
+@subsection Reading a Whole File at Once
 
 Often, it is convenient to have the entire contents of a file available
 in memory as a single string. A straightforward but naive way to
@@ -20468,13 +20640,13 @@ function readfile(file,     tmp, save_rs)
 
 It works by setting @code{RS} to @samp{^$}, a regular expression that
 will never match if the file has contents.  @command{gawk} reads data from
-the file into @code{tmp} attempting to match @code{RS}.  The match fails
+the file into @code{tmp}, attempting to match @code{RS}.  The match fails
 after each read, but fails quickly, such that @command{gawk} fills
 @code{tmp} with the entire contents of the file.
-(@xref{Records}, for information on @code{RT} and @code{RS}.)
+(@DBXREF{Records} for information on @code{RT} and @code{RS}.)
 
 In the case that @code{file} is empty, the return value is the null
-string.  Thus calling code may use something like:
+string.  Thus, calling code may use something like:
 
 @example
 contents = readfile("/some/path")
@@ -20485,11 +20657,11 @@ if (length(contents) == 0)
 This tests the result to see if it is empty or not. An equivalent
 test would be @samp{contents == ""}.
 
-@xref{Extension Sample Readfile}, for an extension function that
+@DBXREF{Extension Sample Readfile} for an extension function that
 also reads an entire file into memory.
 
 @node Shell Quoting
-@subsection Quoting Strings to Pass to The Shell
+@subsection Quoting Strings to Pass to the Shell
 
 @c included by permission
 @ignore
@@ -20531,7 +20703,7 @@ chmod -w file.flac
 
 Note the need for shell quoting.  The function @code{shell_quote()}
 does it.  @code{SINGLE} is the one-character string @code{"'"} and
-@code{QSINGLE} is the three-character string @code{"\"'\""}.
+@code{QSINGLE} is the three-character string @code{"\"'\""}:
 
 @example
 @c file eg/lib/shellquote.awk
@@ -20569,11 +20741,8 @@ function shell_quote(s,             # parameter
 @node Data File Management
 @section @value{DDF} Management
 
-@c STARTOFRANGE dataf
 @cindex files, managing
-@c STARTOFRANGE libfdataf
 @cindex libraries of @command{awk} functions, managing, data files
-@c STARTOFRANGE flibdataf
 @cindex functions, library, managing data files
 This @value{SECTION} presents functions that are useful for managing
 command-line @value{DF}s.
@@ -20591,12 +20760,12 @@ command-line @value{DF}s.
 
 @cindex files, managing, data file boundaries
 @cindex files, initialization and cleanup
-The @code{BEGIN} and @code{END} rules are each executed exactly once at
+The @code{BEGIN} and @code{END} rules are each executed exactly once, at
 the beginning and end of your @command{awk} program, respectively
 (@pxref{BEGIN/END}).
 We (the @command{gawk} authors) once had a user who mistakenly thought that the
-@code{BEGIN} rule is executed at the beginning of each @value{DF} and the
-@code{END} rule is executed at the end of each @value{DF}.
+@code{BEGIN} rules were executed at the beginning of each @value{DF} and the
+@code{END} rules were executed at the end of each @value{DF}.
 
 When informed
 that this was not the case, the user requested that we add new special
@@ -20636,7 +20805,7 @@ END @{ endfile(FILENAME) @}
 This file must be loaded before the user's ``main'' program, so that the
 rule it supplies is executed first.
 
-This rule relies on @command{awk}'s @code{FILENAME} variable that
+This rule relies on @command{awk}'s @code{FILENAME} variable, which
 automatically changes for each new @value{DF}.  The current @value{FN} is
 saved in a private variable, @code{_oldfilename}.  If @code{FILENAME} does
 not equal @code{_oldfilename}, then a new @value{DF} is being processed and
@@ -20652,7 +20821,7 @@ first @value{DF}.
 The program also supplies an @code{END} rule to do the final processing for
 the last file.  Because this @code{END} rule comes before any @code{END} rules
 supplied in the ``main'' program, @code{endfile()} is called first.  Once
-again the value of multiple @code{BEGIN} and @code{END} rules should be clear.
+again, the value of multiple @code{BEGIN} and @code{END} rules should be clear.
 
 @cindex @code{beginfile()} user-defined function
 @cindex @code{endfile()} user-defined function
@@ -20663,7 +20832,7 @@ The following version solves the problem:
 
 @example
 @c file eg/lib/ftrans.awk
-# ftrans.awk --- handle data file transitions
+# ftrans.awk --- handle datafile transitions
 #
 # user supplies beginfile() and endfile() functions
 @c endfile
@@ -20691,26 +20860,27 @@ END @{ endfile(_filename_) @}
 shows how this library function can be used and
 how it simplifies writing the main program.
 
-@sidebar So Why Does @command{gawk} have @code{BEGINFILE} and @code{ENDFILE}?
+@sidebar So Why Does @command{gawk} Have @code{BEGINFILE} and @code{ENDFILE}?
 
 You are probably wondering, if @code{beginfile()} and @code{endfile()}
 functions can do the job, why does @command{gawk} have
-@code{BEGINFILE} and @code{ENDFILE} patterns (@pxref{BEGINFILE/ENDFILE})?
+@code{BEGINFILE} and @code{ENDFILE} patterns?
 
 Good question.  Normally, if @command{awk} cannot open a file, this
 causes an immediate fatal error.  In this case, there is no way for a
-user-defined function to deal with the problem, since the mechanism for
+user-defined function to deal with the problem, as the mechanism for
 calling it relies on the file being open and at the first record.  Thus,
 the main reason for @code{BEGINFILE} is to give you a ``hook'' to catch
 files that cannot be processed.  @code{ENDFILE} exists for symmetry,
 and because it provides an easy way to do per-file cleanup processing.
+For more information, refer to @ref{BEGINFILE/ENDFILE}.
 @end sidebar
 
 @node Rewind Function
 @subsection Rereading the Current File
 
 @cindex files, reading
-Another request for a new built-in function was for a @code{rewind()}
+Another request for a new built-in function was for a
 function that would make it possible to reread the current file.
 The requesting user didn't want to have to use @code{getline}
 (@pxref{Getline})
@@ -20719,7 +20889,7 @@ inside a loop.
 However, as long as you are not in the @code{END} rule, it is
 quite easy to arrange to immediately close the current input file
 and then start over with it from the top.
-For lack of a better name, we'll call it @code{rewind()}:
+For lack of a better name, we'll call the function @code{rewind()}:
 
 @cindex @code{rewind()} user-defined function
 @example
@@ -20757,8 +20927,8 @@ The @code{rewind()} function relies on the @code{ARGIND} variable
 (@pxref{Auto-set}), which is specific to @command{gawk}.  It also
 relies on the @code{nextfile} keyword (@pxref{Nextfile Statement}).
 Because of this, you should not call it from an @code{ENDFILE} rule.
-(This isn't necessary anyway, since as soon as an @code{ENDFILE} rule
-finishes @command{gawk} goes to the next file!)
+(This isn't necessary anyway, because @command{gawk} goes to the next
+file as soon as an @code{ENDFILE} rule finishes!)
 
 @node File Checking
 @subsection Checking for Readable @value{DDF}s
@@ -20806,22 +20976,22 @@ BEGIN @{
 @cindex troubleshooting, @code{getline} function
 This works, because the @code{getline} won't be fatal.
 Removing the element from @code{ARGV} with @code{delete}
-skips the file (since it's no longer in the list).
+skips the file (because it's no longer in the list).
 See also @ref{ARGC and ARGV}.
 
-The regular expression check purposely does not use character classes
+Because @command{awk} variable names only allow the English letters,
+the regular expression check purposely does not use character classes
 such as @samp{[:alpha:]} and @samp{[:alnum:]}
-(@pxref{Bracket Expressions})
-since @command{awk} variable names only allow the English letters.
+(@pxref{Bracket Expressions}).
 
 @node Empty Files
-@subsection Checking for Zero-length Files
+@subsection Checking for Zero-Length Files
 
 All known @command{awk} implementations silently skip over zero-length files.
-This is a by-product of @command{awk}'s implicit 
+This is a by-product of @command{awk}'s implicit
 read-a-record-and-match-against-the-rules loop: when @command{awk}
 tries to read a record from an empty file, it immediately receives an
-end of file indication, closes the file, and proceeds on to the next
+end-of-file indication, closes the file, and proceeds on to the next
 command-line @value{DF}, @emph{without} executing any user-level
 @command{awk} program code.
 
@@ -20886,7 +21056,7 @@ Occasionally, you might not want @command{awk} to process command-line
 variable assignments
 (@pxref{Assignment Options}).
 In particular, if you have a @value{FN} that contains an @samp{=} character,
-@command{awk} treats the @value{FN} as an assignment, and does not process it.
+@command{awk} treats the @value{FN} as an assignment and does not process it.
 
 Some users have suggested an additional command-line option for @command{gawk}
 to disable command-line assignments.  However, some simple programming with
@@ -20936,30 +21106,22 @@ The use of @code{No_command_assign} allows you to disable command-line
 assignments at invocation time, by giving the variable a true value.
 When not set, it is initially zero (i.e., false), so the command-line arguments
 are left alone.
-@c ENDOFRANGE dataf
-@c ENDOFRANGE flibdataf
-@c ENDOFRANGE libfdataf
 
 @node Getopt Function
 @section Processing Command-Line Options
 
-@c STARTOFRANGE libfclo
 @cindex libraries of @command{awk} functions, command-line options
-@c STARTOFRANGE flibclo
 @cindex functions, library, command-line options
-@c STARTOFRANGE clop
 @cindex command-line options, processing
-@c STARTOFRANGE oclp
 @cindex options, command-line, processing
-@c STARTOFRANGE clibf
 @cindex functions, library, C library
 @cindex arguments, processing
-Most utilities on POSIX compatible systems take options on
+Most utilities on POSIX-compatible systems take options on
 the command line that can be used to change the way a program behaves.
 @command{awk} is an example of such a program
 (@pxref{Options}).
-Often, options take @dfn{arguments}; i.e., data that the program needs to
-correctly obey the command-line option.  For example, @command{awk}'s
+Often, options take @dfn{arguments} (i.e., data that the program needs to
+correctly obey the command-line option).  For example, @command{awk}'s
 @option{-F} option requires a string to use as the field separator.
 The first occurrence on the command line of either @option{--} or a
 string that does not begin with @samp{-} ends the options.
@@ -21063,7 +21225,7 @@ necessary for accessing individual characters
 (@pxref{String Functions}).@footnote{This
 function was written before @command{gawk} acquired the ability to
 split strings into single characters using @code{""} as the separator.
-We have left it alone, since using @code{substr()} is more portable.}
+We have left it alone, as using @code{substr()} is more portable.}
 
 The discussion that follows walks through the code a bit at a time:
 
@@ -21231,9 +21393,9 @@ next element in @code{argv}.  If neither condition is true, then only
 on the next call to @code{getopt()}.
 
 The @code{BEGIN} rule initializes both @code{Opterr} and @code{Optind} to one.
-@code{Opterr} is set to one, since the default behavior is for @code{getopt()}
+@code{Opterr} is set to one, because the default behavior is for @code{getopt()}
 to print a diagnostic message upon seeing an invalid option.  @code{Optind}
-is set to one, since there's no reason to look at the program name, which is
+is set to one, because there's no reason to look at the program name, which is
 in @code{ARGV[0]}:
 
 @example
@@ -21256,8 +21418,8 @@ BEGIN @{
 @c endfile
 @end example
 
-The rest of the @code{BEGIN} rule is a simple test program.  Here is the
-result of two sample runs of the test program:
+The rest of the @code{BEGIN} rule is a simple test program.  Here are the
+results of two sample runs of the test program:
 
 @example
 $ @kbd{awk -f getopt.awk -v _getopt_test=1 -- -a -cbARG bax -x}
@@ -21283,46 +21445,44 @@ etc., as its own options.
 
 @quotation NOTE
 After @code{getopt()} is through,
-user level code must clear out all the elements of @code{ARGV} from 1
+user-level code must clear out all the elements of @code{ARGV} from 1
 to @code{Optind}, so that @command{awk} does not try to process the
 command-line options as @value{FN}s.
 @end quotation
 
 Using @samp{#!} with the @option{-E} option may help avoid
 conflicts between your program's options and @command{gawk}'s options,
-since @option{-E} causes @command{gawk} to abandon processing of
+as @option{-E} causes @command{gawk} to abandon processing of
 further options
-(@pxref{Executable Scripts}, and @pxref{Options}).
+(@DBPXREF{Executable Scripts} and
+@ifnotdocbook
+@pxref{Options}).
+@end ifnotdocbook
+@ifdocbook
+@ref{Options}).
+@end ifdocbook
 
 Several of the sample programs presented in
 @ref{Sample Programs},
 use @code{getopt()} to process their arguments.
-@c ENDOFRANGE libfclo
-@c ENDOFRANGE flibclo
-@c ENDOFRANGE clop
-@c ENDOFRANGE oclp
 
 @node Passwd Functions
 @section Reading the User Database
 
-@c STARTOFRANGE libfudata
 @cindex libraries of @command{awk} functions, user database, reading
-@c STARTOFRANGE flibudata
 @cindex functions, library, user database@comma{} reading
-@c STARTOFRANGE udatar
 @cindex user database@comma{} reading
-@c STARTOFRANGE dataur
 @cindex database, users@comma{} reading
 @cindex @code{PROCINFO} array
 The @code{PROCINFO} array
 (@pxref{Built-in Variables})
 provides access to the current user's real and effective user and group ID
-numbers, and if available, the user's supplementary group set.
+numbers, and, if available, the user's supplementary group set.
 However, because these are numbers, they do not provide very useful
 information to the average user.  There needs to be some way to find the
 user information associated with the user and group ID numbers.  This
 @value{SECTION} presents a suite of functions for retrieving information from the
-user database.  @xref{Group Functions},
+user database.  @DBXREF{Group Functions}
 for a similar suite that retrieves information from the group database.
 
 @cindex @code{getpwent()} function (C library)
@@ -21337,11 +21497,11 @@ kept.  Instead, it provides the @code{<pwd.h>} header file
 and several C language subroutines for obtaining user information.
 The primary function is @code{getpwent()}, for ``get password entry.''
 The ``password'' comes from the original user database file,
-@file{/etc/passwd}, which stores user information, along with the
+@file{/etc/passwd}, which stores user information along with the
 encrypted passwords (hence the name).
 
 @cindex @command{pwcat} program
-While an @command{awk} program could simply read @file{/etc/passwd}
+Although an @command{awk} program could simply read @file{/etc/passwd}
 directly, this file may not contain complete information about the
 system's set of users.@footnote{It is often the case that password
 information is stored in a network database.} To be sure you are able to
@@ -21436,12 +21596,12 @@ The user's encrypted password.  This may not be available on some systems.
 
 @item User-ID
 The user's numeric user ID number.
-(On some systems it's a C @code{long}, and not an @code{int}.  Thus
+(On some systems, it's a C @code{long}, and not an @code{int}.  Thus,
 we cast it to @code{long} for all cases.)
 
 @item Group-ID
 The user's numeric group ID number.
-(Similar comments about @code{long} vs.@: @code{int} apply here.)
+(Similar comments about @code{long} versus @code{int} apply here.)
 
 @item Full name
 The user's full name, and perhaps other information associated with the
@@ -21463,7 +21623,7 @@ A few lines representative of @command{pwcat}'s output are as follows:
 @cindex Robbins, Miriam
 @example
 $ @kbd{pwcat}
-@print{} root:3Ov02d5VaUPB6:0:1:Operator:/:/bin/sh
+@print{} root:x:0:1:Operator:/:/bin/sh
 @print{} nobody:*:65534:65534::/:
 @print{} daemon:*:1:1::/:
 @print{} sys:*:2:2::/:/bin/csh
@@ -21542,7 +21702,7 @@ The function @code{_pw_init()} fills three copies of the user information
 into three associative arrays.  The arrays are indexed by username
 (@code{_pw_byname}), by user ID number (@code{_pw_byuid}), and by order of
 occurrence (@code{_pw_bycount}).
-The variable @code{_pw_inited} is used for efficiency, since @code{_pw_init()}
+The variable @code{_pw_inited} is used for efficiency, as @code{_pw_init()}
 needs to be called only once.
 
 @cindex @code{PROCINFO} array, testing the field splitting
@@ -21551,7 +21711,7 @@ Because this function uses @code{getline} to read information from
 @command{pwcat}, it first saves the values of @code{FS}, @code{RS}, and @code{$0}.
 It notes in the variable @code{using_fw} whether field splitting
 with @code{FIELDWIDTHS} is in effect or not.
-Doing so is necessary, since these functions could be called
+Doing so is necessary, as these functions could be called
 from anywhere within a user's program, and the user may have his
 or her own way of splitting records and fields.
 This makes it possible to restore the correct
@@ -21563,7 +21723,7 @@ The code that checks for using @code{FPAT}, using @code{using_fpat}
 and @code{PROCINFO["FS"]}, is similar.
 
 The main part of the function uses a loop to read database lines, split
-the line into fields, and then store the line into each array as necessary.
+the lines into fields, and then store the lines into each array as necessary.
 When the loop is done, @code{@w{_pw_init()}} cleans up by closing the pipeline,
 setting @code{@w{_pw_inited}} to one, and restoring @code{FS}
 (and @code{FIELDWIDTHS} or @code{FPAT}
@@ -21653,26 +21813,18 @@ In turn, calling @code{_pw_init()} is not too expensive, because the
 once.  If you are worried about squeezing every last cycle out of your
 @command{awk} program, the check of @code{_pw_inited} could be moved out of
 @code{_pw_init()} and duplicated in all the other functions.  In practice,
-this is not necessary, since most @command{awk} programs are I/O-bound,
+this is not necessary, as most @command{awk} programs are I/O-bound,
 and such a change would clutter up the code.
 
 The @command{id} program in @DBREF{Id Program}
 uses these functions.
-@c ENDOFRANGE libfudata
-@c ENDOFRANGE flibudata
-@c ENDOFRANGE udatar
-@c ENDOFRANGE dataur
 
 @node Group Functions
 @section Reading the Group Database
 
-@c STARTOFRANGE libfgdata
 @cindex libraries of @command{awk} functions, group database, reading
-@c STARTOFRANGE flibgdata
 @cindex functions, library, group database@comma{} reading
-@c STARTOFRANGE gdatar
 @cindex group database, reading
-@c STARTOFRANGE datagr
 @cindex database, group, reading
 @cindex @code{PROCINFO} array, and group membership
 @cindex @code{getgrent()} function (C library)
@@ -21788,11 +21940,11 @@ it is usually empty or set to @samp{*}.
 @item Group ID Number
 The group's numeric group ID number;
 the association of name to number must be unique within the file.
-(On some systems it's a C @code{long}, and not an @code{int}.  Thus
+(On some systems it's a C @code{long}, and not an @code{int}.  Thus,
 we cast it to @code{long} for all cases.)
 
 @item Group Member List
-A comma-separated list of user names.  These users are members of the group.
+A comma-separated list of usernames.  These users are members of the group.
 Modern Unix systems allow users to be members of several groups
 simultaneously.  If your system does, then there are elements
 @code{"group1"} through @code{"group@var{N}"} in @code{PROCINFO}
@@ -21902,32 +22054,32 @@ The @code{@w{_gr_init()}} function first saves @code{FS},
 @code{$0}, and then sets @code{FS} and @code{RS} to the correct values for
 scanning the group information.
 It also takes care to note whether @code{FIELDWIDTHS} or @code{FPAT}
-is being used, and to restore the appropriate field splitting mechanism.
+is being used, and to restore the appropriate field-splitting mechanism.
 
-The group information is stored is several associative arrays.
+The group information is stored in several associative arrays.
 The arrays are indexed by group name (@code{@w{_gr_byname}}), by group ID number
 (@code{@w{_gr_bygid}}), and by position in the database (@code{@w{_gr_bycount}}).
-There is an additional array indexed by user name (@code{@w{_gr_groupsbyuser}}),
+There is an additional array indexed by username (@code{@w{_gr_groupsbyuser}}),
 which is a space-separated list of groups to which each user belongs.
 
-Unlike the user database, it is possible to have multiple records in the
+Unlike in the user database, it is possible to have multiple records in the
 database for the same group.  This is common when a group has a large number
 of members.  A pair of such entries might look like the following:
 
 @example
-tvpeople:*:101:johny,jay,arsenio
+tvpeople:*:101:johnny,jay,arsenio
 tvpeople:*:101:david,conan,tom,joan
 @end example
 
 For this reason, @code{_gr_init()} looks to see if a group name or
-group ID number is already seen.  If it is, then the user names are
-simply concatenated onto the previous list of users.@footnote{There is actually a
+group ID number is already seen.  If so, the usernames are
+simply concatenated onto the previous list of users.@footnote{There is a
 subtle problem with the code just presented.  Suppose that
 the first time there were no names. This code adds the names with
 a leading comma. It also doesn't check that there is a @code{$4}.}
 
 Finally, @code{_gr_init()} closes the pipeline to @command{grcat}, restores
-@code{FS} (and @code{FIELDWIDTHS} or @code{FPAT} if necessary), @code{RS}, and @code{$0},
+@code{FS} (and @code{FIELDWIDTHS} or @code{FPAT}, if necessary), @code{RS}, and @code{$0},
 initializes @code{_gr_count} to zero
 (it is used later), and makes @code{_gr_inited} nonzero.
 
@@ -21966,7 +22118,7 @@ function getgrgid(gid)
 
 @cindex @code{getgruser()} function (C library)
 The @code{getgruser()} function does not have a C counterpart. It takes a
-user name and returns the list of groups that have the user as a member:
+username and returns the list of groups that have the user as a member:
 
 @cindex @code{getgruser()} function, user-defined
 @example
@@ -21995,7 +22147,6 @@ function getgrent()
 @}
 @c endfile
 @end example
-@c ENDOFRANGE clibf
 
 @cindex @code{endgrent()} function (C library)
 The @code{endgrent()} function resets @code{_gr_count} to zero so that @code{getgrent()} can
@@ -22028,12 +22179,12 @@ uses these functions.
 
 @DBREF{Arrays of Arrays} described how @command{gawk}
 provides arrays of arrays.  In particular, any element of
-an array may be either a scalar, or another array. The
+an array may be either a scalar or another array. The
 @code{isarray()} function (@pxref{Type Functions})
 lets you distinguish an array
 from a scalar.
 The following function, @code{walk_array()}, recursively traverses
-an array, printing each element's indices and value.
+an array, printing the element indices and values.
 You call it with the array and a string representing the name
 of the array:
 
@@ -22084,10 +22235,66 @@ $ @kbd{gawk -f walk_array.awk}
 @print{} a[4][2] = 42
 @end example
 
-@c ENDOFRANGE libfgdata
-@c ENDOFRANGE flibgdata
-@c ENDOFRANGE gdatar
-@c ENDOFRANGE libf
+The function just presented simply prints the
+name and value of each scalar array element. However, it is easy to
+generalize it, by passing in the name of a function to call
+when walking an array. The modified function looks like this:
+
+@example
+@c file eg/lib/processarray.awk
+function process_array(arr, name, process, do_arrays,   i, new_name)
+@{
+    for (i in arr) @{
+        new_name = (name "[" i "]")
+        if (isarray(arr[i])) @{
+            if (do_arrays)
+                @@process(new_name, arr[i])
+            process_array(arr[i], new_name, process, do_arrays)
+        @} else
+            @@process(new_name, arr[i])
+    @}
+@}
+@c endfile
+@end example
+
+The arguments are as follows:
+
+@table @code
+@item arr
+The array.
+
+@item name
+The name of the array (a string).
+
+@item process
+The name of the function to call.
+
+@item do_arrays
+If this is true, the function can handle elements that are subarrays.
+@end table
+
+If subarrays are to be processed, that is done before walking them further.
+
+When run with the following scaffolding, the function produces the same
+results as does the earlier version of @code{walk_array()}:
+
+@example
+BEGIN @{
+    a[1] = 1
+    a[2][1] = 21
+    a[2][2] = 22
+    a[3] = 3
+    a[4][1][1] = 411
+    a[4][2] = 42
+
+    process_array(a, "a", "do_print", 0)
+@}
+
+function do_print(name, element)
+@{
+    printf "%s = %s\n", name, element
+@}
+@end example
 
 @node Library Functions Summary
 @section Summary
@@ -22109,24 +22316,24 @@ The functions presented here fit into the following categories:
 @c nested list
 @table @asis
 @item General problems
-Number to string conversion, assertions, rounding, random number
+Number-to-string conversion, testing assertions, rounding, random number
 generation, converting characters to numbers, joining strings, getting
 easily usable time-of-day information, and reading a whole file in
-one shot.
+one shot
 
 @item Managing @value{DF}s
 Noting @value{DF} boundaries, rereading the current file, checking for
 readable files, checking for zero-length files, and treating assignments
-as @value{FN}s.
+as @value{FN}s
 
 @item Processing command-line options
-An @command{awk} version of the standard C @code{getopt()} function.
+An @command{awk} version of the standard C @code{getopt()} function
 
 @item Reading the user and group databases
-Two sets of routines that parallel the C library versions.
+Two sets of routines that parallel the C library versions
 
 @item Traversing arrays of arrays
-A simple function to traverse an array of arrays to any depth.
+Two functions that traverse an array of arrays to any depth
 @end table
 @c end nested list
 
@@ -22169,7 +22376,7 @@ ARGIND != Argind @{
 @}
 END @{
     if (ARGIND < ARGC - 1)
-        ARGIND = ARGC - 1 
+        ARGIND = ARGC - 1
     if (ARGIND > Argind)
         for (Argind++; Argind <= ARGIND; Argind++)
             zerofile(ARGV[Argind], Argind)
@@ -22201,13 +22408,9 @@ output identical to that of the original version.
 @end enumerate
 @c EXCLUDE END
 
-@c ENDOFRANGE flib
-@c ENDOFRANGE fudlib
-@c ENDOFRANGE datagr
 
 @node Sample Programs
 @chapter Practical @command{awk} Programs
-@c STARTOFRANGE awkpex
 @cindex @command{awk} programs, examples of
 
 @c FULLXREF ON
@@ -22225,10 +22428,10 @@ in this @value{CHAPTER}.
 The second presents @command{awk}
 versions of several common POSIX utilities.
 These are programs that you are hopefully already familiar with,
-and therefore, whose problems are understood.
+and therefore whose problems are understood.
 By reimplementing these programs in @command{awk},
 you can focus on the @command{awk}-related aspects of solving
-the programming problem.
+the programming problems.
 
 The third is a grab bag of interesting programs.
 These solve a number of different data-manipulation and management
@@ -22277,7 +22480,6 @@ cut.awk -- -c1-8 myfiles > results
 
 @node Clones
 @section Reinventing Wheels for Fun and Profit
-@c STARTOFRANGE posimawk
 @cindex POSIX, programs@comma{} implementing in @command{awk}
 
 This @value{SECTION} presents a number of POSIX utilities implemented in
@@ -22289,7 +22491,7 @@ It should be noted that these programs are not necessarily intended to
 replace the installed versions on your system.
 Nor may all of these programs be fully compliant with the most recent
 POSIX standard.  This is not a problem; their
-purpose is to illustrate @command{awk} language programming for ``real world''
+purpose is to illustrate @command{awk} language programming for ``real-world''
 tasks.
 
 The programs are presented in alphabetical order.
@@ -22305,14 +22507,11 @@ The programs are presented in alphabetical order.
 @end menu
 
 @node Cut Program
-@subsection Cutting out Fields and Columns
+@subsection Cutting Out Fields and Columns
 
 @cindex @command{cut} utility
-@c STARTOFRANGE cut
 @cindex @command{cut} utility
-@c STARTOFRANGE ficut
 @cindex fields, cutting
-@c STARTOFRANGE colcut
 @cindex columns, cutting
 The @command{cut} utility selects, or ``cuts,'' characters or fields
 from its standard input and sends them to its standard output.
@@ -22321,7 +22520,7 @@ but you may supply a command-line option to change the field
 @dfn{delimiter} (i.e., the field-separator character). @command{cut}'s
 definition of fields is less general than @command{awk}'s.
 
-A common use of @command{cut} might be to pull out just the login name of
+A common use of @command{cut} might be to pull out just the login names of
 logged-on users from the output of @command{who}.  For example, the following
 pipeline generates a sorted, unique list of the logged-on users:
 
@@ -22582,7 +22781,7 @@ function set_charlist(    field, i, j, f, g, n, m, t,
 @c endfile
 @end example
 
-Next is the rule that actually processes the data.  If the @option{-s} option
+Next is the rule that processes the data.  If the @option{-s} option
 is given, then @code{suppress} is true.  The first @code{if} statement
 makes sure that the input record does have the field separator.  If
 @command{cut} is processing fields, @code{suppress} is true, and the field
@@ -22614,27 +22813,20 @@ written out between the fields:
 @end example
 
 This version of @command{cut} relies on @command{gawk}'s @code{FIELDWIDTHS}
-variable to do the character-based cutting.  While it is possible in
+variable to do the character-based cutting.  It is possible in
 other @command{awk} implementations to use @code{substr()}
-(@pxref{String Functions}),
+(@pxref{String Functions}), but
 it is also extremely painful.
 The @code{FIELDWIDTHS} variable supplies an elegant solution to the problem
 of picking the input line apart by characters.
-@c ENDOFRANGE cut
-@c ENDOFRANGE ficut
-@c ENDOFRANGE colcut
 
 
 @node Egrep Program
 @subsection Searching for Regular Expressions in Files
 
-@c STARTOFRANGE regexps
 @cindex regular expressions, searching for
-@c STARTOFRANGE sfregexp
 @cindex searching, files for regular expressions
-@c STARTOFRANGE fsregexp
 @cindex files, searching for regular expressions
-@c STARTOFRANGE egrep
 @cindex @command{egrep} utility
 The @command{egrep} utility searches files for patterns.  It uses regular
 expressions that are almost identical to those available in @command{awk}
@@ -22761,7 +22953,7 @@ matched lines in the output:
 @c endfile
 @end example
 
-The last two lines are commented out, since they are not needed in
+The last two lines are commented out, as they are not needed in
 @command{gawk}.  They should be uncommented if you have to use another version
 of @command{awk}.
 
@@ -22771,7 +22963,7 @@ into lowercase if the @option{-i} option is specified.@footnote{It
 also introduces a subtle bug;
 if a match happens, we output the translated line, not the original.}
 The rule is
-commented out since it is not necessary with @command{gawk}:
+commented out as it is not necessary with @command{gawk}:
 
 @example
 @c file eg/prog/egrep.awk
@@ -22837,7 +23029,7 @@ successful or unsuccessful match.  If the line does not match, the
 @code{next} statement just moves on to the next record.
 
 A number of additional tests are made, but they are only done if we
-are not counting lines.  First, if the user only wants exit status
+are not counting lines.  First, if the user only wants the exit status
 (@code{no_print} is true), then it is enough to know that @emph{one}
 line in this file matched, and we can skip on to the next file with
 @code{nextfile}.  Similarly, if we are only printing @value{FN}s, we can
@@ -22878,7 +23070,7 @@ if necessary:
 @end example
 
 The @code{END} rule takes care of producing the correct exit status. If
-there are no matches, the exit status is one; otherwise it is zero:
+there are no matches, the exit status is one; otherwise, it is zero:
 
 @example
 @c file eg/prog/egrep.awk
@@ -22902,17 +23094,12 @@ function usage()
 @c endfile
 @end example
 
-@c ENDOFRANGE regexps
-@c ENDOFRANGE sfregexp
-@c ENDOFRANGE fsregexp
-@c ENDOFRANGE egrep
 
 @node Id Program
-@subsection Printing out User Information
+@subsection Printing Out User Information
 
 @cindex printing, user information
 @cindex users, information about, printing
-@c STARTOFRANGE id
 @cindex @command{id} utility
 The @command{id} utility lists a user's real and effective user ID numbers,
 real and effective group ID numbers, and the user's group set, if any.
@@ -22935,7 +23122,8 @@ Here is a simple version of @command{id} written in @command{awk}.
 It uses the user database library functions
 (@pxref{Passwd Functions})
 and the group database library functions
-(@pxref{Group Functions}):
+(@pxref{Group Functions})
+from @ref{Library Functions}.
 
 The program is fairly straightforward.  All the work is done in the
 @code{BEGIN} rule.  The user and group ID numbers are obtained from
@@ -23023,7 +23211,7 @@ function pr_first_field(str,  a)
 The test in the @code{for} loop is worth noting.
 Any supplementary groups in the @code{PROCINFO} array have the
 indices @code{"group1"} through @code{"group@var{N}"} for some
-@var{N}, i.e., the total number of supplementary groups.
+@var{N} (i.e., the total number of supplementary groups).
 However, we don't know in advance how many of these groups
 there are.
 
@@ -23041,16 +23229,13 @@ code that is used repeatedly, making the whole program
 shorter and cleaner. In particular, moving the check for
 the empty string into this function saves several lines of code.
 
-@c ENDOFRANGE id
 
 @node Split Program
 @subsection Splitting a Large File into Pieces
 
 @c FIXME: One day, update to current POSIX version of split
 
-@c STARTOFRANGE filspl
 @cindex files, splitting
-@c STARTOFRANGE split
 @cindex @code{split} utility
 The @command{split} program splits large text files into smaller pieces.
 Usage is as follows:@footnote{This is the traditional usage. The
@@ -23063,10 +23248,10 @@ aims to demonstrate.}
 
 By default,
 the output files are named @file{xaa}, @file{xab}, and so on. Each file has
-1000 lines in it, with the likely exception of the last file. To change the
+1,000 lines in it, with the likely exception of the last file. To change the
 number of lines in each file, supply a number on the command line
-preceded with a minus; e.g., @samp{-500} for files with 500 lines in them
-instead of 1000.  To change the name of the output files to something like
+preceded with a minus sign (e.g., @samp{-500} for files with 500 lines in them
+instead of 1,000).  To change the names of the output files to something like
 @file{myfileaa}, @file{myfileab}, and so on, supply an additional
 argument that specifies the @value{FN} prefix.
 
@@ -23114,7 +23299,7 @@ BEGIN @{
     @}
     # test argv in case reading from stdin instead of file
     if (i in ARGV)
-        i++    # skip data file name
+        i++    # skip datafile name
     if (i in ARGV) @{
         outfile = ARGV[i]
         ARGV[i] = ""
@@ -23185,15 +23370,12 @@ You might want to consider how to eliminate the use of
 way as to solve the EBCDIC issue as well.
 @end ifset
 
-@c ENDOFRANGE filspl
-@c ENDOFRANGE split
 
 @node Tee Program
 @subsection Duplicating Output into Multiple Files
 
 @cindex files, multiple@comma{} duplicating output into
 @cindex output, duplicating into files
-@c STARTOFRANGE tee
 @cindex @code{tee} utility
 The @code{tee} program is known as a ``pipe fitting.''  @code{tee} copies
 its standard input to its standard output and also duplicates it to the
@@ -23208,8 +23390,8 @@ truncating them and starting over.
 
 The @code{BEGIN} rule first makes a copy of all the command-line arguments
 into an array named @code{copy}.
-@code{ARGV[0]} is not copied, since it is not needed.
-@code{tee} cannot use @code{ARGV} directly, since @command{awk} attempts to
+@code{ARGV[0]} is not needed, so it is not copied.
+@code{tee} cannot use @code{ARGV} directly, because @command{awk} attempts to
 process each @value{FN} in @code{ARGV} as input data.
 
 @cindex flag variables
@@ -23258,7 +23440,7 @@ BEGIN @{
 @c endfile
 @end example
 
-The following single rule does all the work.  Since there is no pattern, it is
+The following single rule does all the work.  Because there is no pattern, it is
 executed for each line of input.  The body of the rule simply prints the
 line into each file on the command line, and then to the standard output:
 
@@ -23289,7 +23471,7 @@ for (i in copy)
 @end example
 
 @noindent
-This is more concise but it is also less efficient.  The @samp{if} is
+This is more concise, but it is also less efficient.  The @samp{if} is
 tested for each record and for each output file.  By duplicating the loop
 body, the @samp{if} is only tested once for each input record.  If there are
 @var{N} input records and @var{M} output files, the first method only
@@ -23306,18 +23488,14 @@ END @{
 @}
 @c endfile
 @end example
-@c ENDOFRANGE tee
 
 @node Uniq Program
 @subsection Printing Nonduplicated Lines of Text
 
 @c FIXME: One day, update to current POSIX version of uniq
 
-@c STARTOFRANGE prunt
 @cindex printing, unduplicated lines of text
-@c STARTOFRANGE tpul
 @cindex text@comma{} printing, unduplicated lines of
-@c STARTOFRANGE uniq
 @cindex @command{uniq} utility
 The @command{uniq} utility reads sorted lines of data on its standard
 input, and by default removes duplicate lines.  In other words, it only
@@ -23509,10 +23687,10 @@ The second rule does the work. The variable @code{equal} is one or zero,
 depending upon the results of @code{are_equal()}'s comparison. If @command{uniq}
 is counting repeated lines, and the lines are equal, then it increments the @code{count} variable.
 Otherwise, it prints the line and resets @code{count},
-since the two lines are not equal.
+because the two lines are not equal.
 
 If @command{uniq} is not counting, and if the lines are equal, @code{count} is incremented.
-Nothing is printed, since the point is to remove duplicates.
+Nothing is printed, as the point is to remove duplicates.
 Otherwise, if @command{uniq} is counting repeated lines and more than
 one line is seen, or if @command{uniq} is counting nonrepeated lines
 and only one line is seen, then the line is printed, and @code{count}
@@ -23581,31 +23759,22 @@ Brian Kernighan suggests that
 ``an alternative approach to state machines is to just read
 the input into an array, then use indexing.  It's almost always
 easier code, and for most inputs where you would use this, just
-as fast.''  Consider how to rewrite the logic to follow this 
+as fast.''  Consider how to rewrite the logic to follow this
 suggestion.
 @end ifset
 
 
-@c ENDOFRANGE prunt
-@c ENDOFRANGE tpul
-@c ENDOFRANGE uniq
 
 @node Wc Program
 @subsection Counting Things
 
 @c FIXME: One day, update to current POSIX version of wc
 
-@c STARTOFRANGE count
 @cindex counting
-@c STARTOFRANGE infco
 @cindex input files, counting elements in
-@c STARTOFRANGE woco
 @cindex words, counting
-@c STARTOFRANGE chco
 @cindex characters, counting
-@c STARTOFRANGE lico
 @cindex lines, counting
-@c STARTOFRANGE wc
 @cindex @command{wc} utility
 The @command{wc} (word count) utility counts lines, words, and characters in
 one or more input files. Its usage is as follows:
@@ -23633,7 +23802,7 @@ Count only characters.
 @end table
 
 Implementing @command{wc} in @command{awk} is particularly elegant,
-since @command{awk} does a lot of the work for us; it splits lines into
+because @command{awk} does a lot of the work for us; it splits lines into
 words (i.e., fields) and counts them, it counts lines (i.e., records),
 and it can easily tell us how long a line is.
 
@@ -23738,7 +23907,7 @@ function endfile(file)
 @end example
 
 There is one rule that is executed for each line. It adds the length of
-the record, plus one, to @code{chars}.@footnote{Since @command{gawk}
+the record, plus one, to @code{chars}.@footnote{Because @command{gawk}
 understands multibyte locales, this code counts characters, not bytes.}
 Adding one plus the record length
 is needed because the newline character separating records (the value
@@ -23775,13 +23944,6 @@ END @{
 @}
 @c endfile
 @end example
-@c ENDOFRANGE count
-@c ENDOFRANGE infco
-@c ENDOFRANGE lico
-@c ENDOFRANGE woco
-@c ENDOFRANGE chco
-@c ENDOFRANGE wc
-@c ENDOFRANGE posimawk
 
 @node Miscellaneous Programs
 @section A Grab Bag of @command{awk} Programs
@@ -23912,9 +24074,7 @@ Aharon Robbins <arnold@skeeve.com> wrote:
 @author Erik Quanstrom
 @end quotation
 
-@c STARTOFRANGE tialarm
 @cindex time, alarm clock example program
-@c STARTOFRANGE alaex
 @cindex alarm clock example program
 The following program is a simple ``alarm clock'' program.
 You give it a time of day and an optional message.  At the specified time,
@@ -23930,7 +24090,7 @@ checking and setting of defaults: the delay, the count, and the message to
 print.  If the user supplied a message without the ASCII BEL
 character (known as the ``alert'' character, @code{"\a"}), then it is added to
 the message.  (On many systems, printing the ASCII BEL generates an
-audible alert. Thus when the alarm goes off, the system calls attention
+audible alert. Thus, when the alarm goes off, the system calls attention
 to itself in case the user is not looking at the computer.)
 Just for a change, this program uses a @code{switch} statement
 (@pxref{Switch Statement}), but the processing could be done with a series of
@@ -24066,15 +24226,11 @@ seconds are necessary:
 @}
 @c endfile
 @end example
-@c ENDOFRANGE tialarm
-@c ENDOFRANGE alaex
 
 @node Translate Program
 @subsection Transliterating Characters
 
-@c STARTOFRANGE chtra
 @cindex characters, transliterating
-@c STARTOFRANGE tr
 @cindex @command{tr} utility
 The system @command{tr} utility transliterates characters.  For example, it is
 often used to map uppercase letters into lowercase for further processing:
@@ -24086,8 +24242,8 @@ often used to map uppercase letters into lowercase for further processing:
 @command{tr} requires two lists of characters.@footnote{On some older
 systems, including Solaris, the system version of @command{tr} may require
 that the lists be written as range expressions enclosed in square brackets
-(@samp{[a-z]}) and quoted, to prevent the shell from attempting a file
-name expansion.  This is not a feature.}  When processing the input, the
+(@samp{[a-z]}) and quoted, to prevent the shell from attempting a
+@value{FN} expansion.  This is not a feature.}  When processing the input, the
 first character in the first list is replaced with the first character
 in the second list, the second character in the first list is replaced
 with the second character in the second list, and so on.  If there are
@@ -24103,7 +24259,7 @@ to @command{gawk}.
 @c at least theoretically
 The following program was written to
 prove that character transliteration could be done with a user-level
-function.  This program is not as complete as the system @command{tr} utility
+function.  This program is not as complete as the system @command{tr} utility,
 but it does most of the job.
 
 The @command{translate} program was written long before @command{gawk}
@@ -24115,13 +24271,13 @@ takes three arguments:
 
 @table @code
 @item from
-A list of characters from which to translate.
+A list of characters from which to translate
 
 @item to
-A list of characters to which to translate.
+A list of characters to which to translate
 
 @item target
-The string on which to do the translation.
+The string on which to do the translation
 @end table
 
 Associative arrays make the translation part fairly easy. @code{t_ar} holds
@@ -24130,7 +24286,7 @@ loop goes through @code{from}, one character at a time.  For each character
 in @code{from}, if the character appears in @code{target},
 it is replaced with the corresponding @code{to} character.
 
-The @code{translate()} function calls @code{stranslate()} using @code{$0}
+The @code{translate()} function calls @code{stranslate()}, using @code{$0}
 as the target.  The main program sets two global variables, @code{FROM} and
 @code{TO}, from the command line, and then changes @code{ARGV} so that
 @command{awk} reads from the standard input.
@@ -24152,7 +24308,7 @@ Finally, the processing rule simply calls @code{translate()} for each record:
 @c endfile
 @end ignore
 @c file eg/prog/translate.awk
-# Bugs: does not handle things like: tr A-Z a-z, it has
+# Bugs: does not handle things like tr A-Z a-z; it has
 # to be spelled out. However, if `to' is shorter than `from',
 # the last character in `to' is used for the rest of `from'.
 
@@ -24202,9 +24358,9 @@ BEGIN @{
 @c endfile
 @end example
 
-While it is possible to do character transliteration in a user-level
-function, it is not necessarily efficient, and we (the @command{gawk}
-authors) started to consider adding a built-in function.  However,
+It is possible to do character transliteration in a user-level
+function, but it is not necessarily efficient, and we (the @command{gawk}
+developers) started to consider adding a built-in function.  However,
 shortly after writing this program, we learned that Brian Kernighan
 had added the @code{toupper()} and @code{tolower()} functions to his
 @command{awk} (@pxref{String Functions}).  These functions handle the
@@ -24222,17 +24378,13 @@ such as @samp{a-z}, as allowed by the @command{tr} utility.
 Look at the code for @file{cut.awk} (@pxref{Cut Program})
 for inspiration.
 
-@c ENDOFRANGE chtra
-@c ENDOFRANGE tr
 
 @node Labels Program
 @subsection Printing Mailing Labels
 
-@c STARTOFRANGE prml
 @cindex printing, mailing labels
-@c STARTOFRANGE mlprint
 @cindex mailing labels@comma{} printing
-Here is a ``real world''@footnote{``Real world'' is defined as
+Here is a ``real-world''@footnote{``Real world'' is defined as
 ``a program actually used to get something done.''}
 program.  This
 script reads lists of names and
@@ -24241,14 +24393,14 @@ on it, two across and 10 down.  The addresses are guaranteed to be no more
 than five lines of data.  Each address is separated from the next by a blank
 line.
 
-The basic idea is to read 20 labels worth of data.  Each line of each label
+The basic idea is to read 20 labels' worth of data.  Each line of each label
 is stored in the @code{line} array.  The single rule takes care of filling
 the @code{line} array and printing the page when 20 labels have been read.
 
 The @code{BEGIN} rule simply sets @code{RS} to the empty string, so that
 @command{awk} splits records at blank lines
 (@pxref{Records}).
-It sets @code{MAXLINES} to 100, since 100 is the maximum number
+It sets @code{MAXLINES} to 100, because 100 is the maximum number
 of lines on the page
 @iftex
 (@math{20 @cdot 5 = 100}).
@@ -24264,12 +24416,12 @@ of lines on the page
 
 Most of the work is done in the @code{printpage()} function.
 The label lines are stored sequentially in the @code{line} array.  But they
-have to print horizontally; @code{line[1]} next to @code{line[6]},
+have to print horizontally: @code{line[1]} next to @code{line[6]},
 @code{line[2]} next to @code{line[7]}, and so on.  Two loops
 accomplish this.  The outer loop, controlled by @code{i}, steps through
 every 10 lines of data; this is each row of labels.  The inner loop,
 controlled by @code{j}, goes through the lines within the row.
-As @code{j} goes from 0 to 4, @samp{i+j} is the @code{j}-th line in
+As @code{j} goes from 0 to 4, @samp{i+j} is the @code{j}th line in
 the row, and @samp{i+j+5} is the entry next to it.  The output ends up
 looking something like this:
 
@@ -24294,7 +24446,6 @@ that there are two blank lines at the top and two blank lines at the bottom.
 The @code{END} rule arranges to flush the final page of labels; there may
 not have been an even multiple of 20 labels in the data:
 
-@c STARTOFRANGE labels
 @cindex @code{labels.awk} program
 @example
 @c file eg/prog/labels.awk
@@ -24359,14 +24510,10 @@ END @{
 @}
 @c endfile
 @end example
-@c ENDOFRANGE prml
-@c ENDOFRANGE mlprint
-@c ENDOFRANGE labels
 
 @node Word Sorting
 @subsection Generating Word-Usage Counts
 
-@c STARTOFRANGE worus
 @cindex words, usage counts@comma{} generating
 
 When working with large amounts of text, it can be interesting to know
@@ -24392,8 +24539,8 @@ END @{
 @}
 @end example
 
-The program relies on @command{awk}'s default field splitting
-mechanism to break each line up into ``words,'' and uses an
+The program relies on @command{awk}'s default field-splitting
+mechanism to break each line up into ``words'' and uses an
 associative array named @code{freq}, indexed by each word, to count
 the number of times the word occurs. In the @code{END} rule,
 it prints the counts.
@@ -24405,9 +24552,9 @@ useful on real text files:
 @item
 The @command{awk} language considers upper- and lowercase characters to be
 distinct.  Therefore, ``bartender'' and ``Bartender'' are not treated
-as the same word.  This is undesirable, since in normal text, words
-are capitalized if they begin sentences, and a frequency analyzer should not
-be sensitive to capitalization.
+as the same word.  This is undesirable, because words are capitalized
+if they begin sentences in normal text, and a frequency analyzer should
+not be sensitive to capitalization.
 
 @item
 Words are detected using the @command{awk} convention that fields are
@@ -24428,7 +24575,6 @@ to remove punctuation characters.  Finally, we solve the third problem
 by using the system @command{sort} utility to process the output of the
 @command{awk} script.  Here is the new version of the program:
 
-@c STARTOFRANGE wordfreq
 @cindex @code{wordfreq.awk} program
 @example
 @c file eg/prog/wordfreq.awk
@@ -24449,8 +24595,8 @@ END @{
 @}
 @end example
 
-The regexp @samp{/[^[:alnum:]_[:blank:]]/} might have been written
-@samp{/[[:punct:]]/}, but then underscores would also be removed,
+The regexp @code{/[^[:alnum:]_[:blank:]]/} might have been written
+@code{/[[:punct:]]/}, but then underscores would also be removed,
 and we want to keep them.
 
 Assuming we have saved this program in a file named @file{wordfreq.awk},
@@ -24493,16 +24639,13 @@ This way of sorting must be used on systems that do not
 have true pipes at the command-line (or batch-file) level.
 See the general operating system documentation for more information on how
 to use the @command{sort} program.
-@c ENDOFRANGE worus
-@c ENDOFRANGE wordfreq
 
 @node History Sorting
 @subsection Removing Duplicates from Unsorted Text
 
-@c STARTOFRANGE lidu
 @cindex lines, duplicate@comma{} removing
 The @command{uniq} program
-(@pxref{Uniq Program}),
+(@pxref{Uniq Program})
 removes duplicate lines from @emph{sorted} data.
 
 Suppose, however, you need to remove duplicate lines from a @value{DF} but
@@ -24524,7 +24667,6 @@ Each element of @code{lines} is a unique command, and the indices of
 The @code{END} rule simply prints out the lines, in order:
 
 @cindex Rakitzis, Byron
-@c STARTOFRANGE histsort
 @cindex @code{histsort.awk} program
 @example
 @c file eg/prog/histsort.awk
@@ -24567,15 +24709,11 @@ print data[lines[i]], lines[i]
 @noindent
 This works because @code{data[$0]} is incremented each time a line is
 seen.
-@c ENDOFRANGE lidu
-@c ENDOFRANGE histsort
 
 @node Extract Program
 @subsection Extracting Programs from Texinfo Source Files
 
-@c STARTOFRANGE texse
 @cindex Texinfo, extracting programs from source files
-@c STARTOFRANGE fitex
 @cindex files, Texinfo@comma{} extracting programs from
 @ifnotinfo
 Both this chapter and the previous chapter
@@ -24588,13 +24726,13 @@ The nodes
 and @ref{Sample Programs},
 are the top level nodes for a large number of @command{awk} programs.
 @end ifinfo
-If you want to experiment with these programs, it is tedious to have to type
+If you want to experiment with these programs, it is tedious to type
 them in by hand.  Here we present a program that can extract parts of a
 Texinfo input file into separate files.
 
 @cindex Texinfo
 This @value{DOCUMENT} is written in @uref{http://www.gnu.org/software/texinfo/, Texinfo},
-the GNU project's document formatting language.
+the GNU Project's document formatting language.
 A single Texinfo source file can be used to produce both
 printed documentation, with @TeX{}, and online documentation.
 @ifnotinfo
@@ -24653,7 +24791,7 @@ The Texinfo file looks something like this:
 
 @example
 @dots{}
-This program has a @@code@{BEGIN@} rule,
+This program has a @@code@{BEGIN@} rule
 that prints a nice message:
 
 @@example
@@ -24666,7 +24804,7 @@ It also prints some final advice:
 
 @@example
 @@c file examples/messages.awk
-END @@@{ print "Always avoid bored archeologists!" @@@}
+END @@@{ print "Always avoid bored archaeologists!" @@@}
 @@c end file
 @@end example
 @dots{}
@@ -24679,11 +24817,10 @@ The first rule handles calling @code{system()}, checking that a command is
 given (@code{NF} is at least three) and also checking that the command
 exits with a zero exit status, signifying OK:
 
-@c STARTOFRANGE extract
 @cindex @code{extract.awk} program
 @example
 @c file eg/prog/extract.awk
-# extract.awk --- extract files and run programs from texinfo files
+# extract.awk --- extract files and run programs from Texinfo files
 @c endfile
 @ignore
 @c file eg/prog/extract.awk
@@ -24724,12 +24861,12 @@ The second rule handles moving data into files.  It verifies that a
 @value{FN} is given in the directive.  If the file named is not the
 current file, then the current file is closed.  Keeping the current file
 open until a new file is encountered allows the use of the @samp{>}
-redirection for printing the contents, keeping open file management
+redirection for printing the contents, keeping open-file management
 simple.
 
 The @code{for} loop does the work.  It reads lines using @code{getline}
 (@pxref{Getline}).
-For an unexpected end of file, it calls the @code{@w{unexpected_eof()}}
+For an unexpected end-of-file, it calls the @code{@w{unexpected_eof()}}
 function.  If the line is an ``endfile'' line, then it breaks out of
 the loop.
 If the line is an @samp{@@group} or @samp{@@end group} line, then it
@@ -24825,20 +24962,17 @@ END @{
 @}
 @c endfile
 @end example
-@c ENDOFRANGE texse
-@c ENDOFRANGE fitex
-@c ENDOFRANGE extract
 
 @node Simple Sed
 @subsection A Simple Stream Editor
 
 @cindex @command{sed} utility
 @cindex stream editors
-The @command{sed} utility is a stream editor, a program that reads a
+The @command{sed} utility is a @dfn{stream editor}, a program that reads a
 stream of data, makes changes to it, and passes it on.
 It is often used to make global changes to a large file or to a stream
 of data generated by a pipeline of commands.
-While @command{sed} is a complicated program in its own right, its most common
+Although @command{sed} is a complicated program in its own right, its most common
 use is to perform global substitutions in the middle of a pipeline:
 
 @example
@@ -24847,7 +24981,7 @@ use is to perform global substitutions in the middle of a pipeline:
 
 Here, @samp{s/old/new/g} tells @command{sed} to look for the regexp
 @samp{old} on each input line and globally replace it with the text
-@samp{new}, i.e., all the occurrences on a line.  This is similar to
+@samp{new} (i.e., all the occurrences on a line).  This is similar to
 @command{awk}'s @code{gsub()} function
 (@pxref{String Functions}).
 
@@ -24857,7 +24991,6 @@ additional arguments are treated as @value{DF} names to process. If none
 are provided, the standard input is used:
 
 @cindex Brennan, Michael
-@c STARTOFRANGE awksed
 @cindex @command{awksed.awk} program
 @c @cindex simple stream editor
 @c @cindex stream editor, simple
@@ -24931,17 +25064,14 @@ not treated as @value{FN}s
 (@pxref{ARGC and ARGV}).
 
 The @code{usage()} function prints an error message and exits.
-Finally, the single rule handles the printing scheme outlined above,
+Finally, the single rule handles the printing scheme outlined earlier,
 using @code{print} or @code{printf} as appropriate, depending upon the
 value of @code{RT}.
-@c ENDOFRANGE awksed
 
 @node Igawk Program
 @subsection An Easy Way to Use Library Functions
 
-@c STARTOFRANGE libfex
 @cindex libraries of @command{awk} functions, example program for using
-@c STARTOFRANGE flibex
 @cindex functions, library, example program for using
 In @ref{Include Files}, we saw how @command{gawk} provides a built-in
 file-inclusion capability.  However, this is a @command{gawk} extension.
@@ -24975,15 +25105,15 @@ BEGIN @{
 
 The following program, @file{igawk.sh}, provides this service.
 It simulates @command{gawk}'s searching of the @env{AWKPATH} variable
-and also allows @dfn{nested} includes; i.e., a file that is included
-with @code{@@include} can contain further @code{@@include} statements.
+and also allows @dfn{nested} includes (i.e., a file that is included
+with @code{@@include} can contain further @code{@@include} statements).
 @command{igawk} makes an effort to only include files once, so that nested
 includes don't accidentally include a library function twice.
 
 @command{igawk} should behave just like @command{gawk} externally.  This
 means it should accept all of @command{gawk}'s command-line arguments,
 including the ability to have multiple source files specified via
-@option{-f}, and the ability to mix command-line and library source files.
+@option{-f} and the ability to mix command-line and library source files.
 
 The program is written using the POSIX Shell (@command{sh}) command
 language.@footnote{Fully explaining the @command{sh} language is beyond
@@ -25006,10 +25136,10 @@ Literal text, provided with @option{-e} or @option{--source}.  This
 text is just appended directly.
 
 @item
-Source @value{FN}s, provided with @option{-f}.  We use a neat trick and append
-@samp{@@include @var{filename}} to the shell variable's contents.  Since the file-inclusion
-program works the way @command{gawk} does, this gets the text
-of the file included into the program at the correct point.
+Source @value{FN}s, provided with @option{-f}.  We use a neat trick and
+append @samp{@@include @var{filename}} to the shell variable's contents.
+Because the file-inclusion program works the way @command{gawk} does, this
+gets the text of the file included in the program at the correct point.
 @end enumerate
 
 @item
@@ -25022,7 +25152,7 @@ Run the expanded program with @command{gawk} and any other original command-line
 arguments that the user supplied (such as the @value{DF} names).
 @end enumerate
 
-This program uses shell variables extensively: for storing command-line arguments,
+This program uses shell variables extensively: for storing command-line arguments and
 the text of the @command{awk} program that will expand the user's program, for the
 user's original program, and for the expanded program.  Doing so removes some
 potential problems that might arise were we to use temporary files instead,
@@ -25080,7 +25210,6 @@ program.
 
 The program is as follows:
 
-@c STARTOFRANGE igawk
 @cindex @code{igawk.sh} program
 @example
 @c file eg/prog/igawk.sh
@@ -25308,9 +25437,10 @@ EOF
 @c endfile
 @end example
 
-The shell construct @samp{@var{command} << @var{marker}} is called a @dfn{here document}.
-Everything in the shell script up to the @var{marker} is fed to @var{command} as input.
-The shell processes the contents of the here document for variable and command substitution
+The shell construct @samp{@var{command} << @var{marker}} is called
+a @dfn{here document}.  Everything in the shell script up to the
+@var{marker} is fed to @var{command} as input.  The shell processes
+the contents of the here document for variable and command substitution
 (and possibly other things as well, depending upon the shell).
 
 The shell construct @samp{$(@dots{})} is called @dfn{command substitution}.
@@ -25325,34 +25455,21 @@ It's done in these steps:
 @enumerate
 @item
 Run @command{gawk} with the @code{@@include}-processing program (the
-value of the @code{expand_prog} shell variable) on standard input.
+value of the @code{expand_prog} shell variable) reading standard input.
 
 @item
-Standard input is the contents of the user's program, from the shell variable @code{program}.
-Its contents are fed to @command{gawk} via a here document.
+Standard input is the contents of the user's program,
+from the shell variable @code{program}.
+Feed its contents to @command{gawk} via a here document.
 
 @item
-The results of this processing are saved in the shell variable @code{processed_program} by using command substitution.
+Save the results of this processing in the shell variable
+@code{processed_program} by using command substitution.
 @end enumerate
 
 The last step is to call @command{gawk} with the expanded program,
 along with the original
-options and command-line arguments that the user supplied.
-
-@c this causes more problems than it solves, so leave it out.
-@ignore
-The special file @file{/dev/null} is passed as a @value{DF} to @command{gawk}
-to handle an interesting case. Suppose that the user's program only has
-a @code{BEGIN} rule and there are no @value{DF}s to read.
-The program should exit without reading any @value{DF}s.
-However, suppose that an included library file defines an @code{END}
-rule of its own. In this case, @command{gawk} will hang, reading standard
-input. In order to avoid this, @file{/dev/null} is explicitly added to the
-command line. Reading from @file{/dev/null} always returns an immediate
-end of file indication.
-
-@c Hmm. Add /dev/null if $# is 0?  Still messes up ARGV. Sigh.
-@end ignore
+options and command-line arguments that the user supplied:
 
 @example
 @c file eg/prog/igawk.sh
@@ -25402,13 +25519,9 @@ features to a program; they can often be layered on top.@footnote{@command{gawk}
 does @code{@@include} processing itself in order to support the use
 of @command{awk} programs as Web CGI scripts.}
 
-@c ENDOFRANGE libfex
-@c ENDOFRANGE flibex
-@c ENDOFRANGE awkpex
-@c ENDOFRANGE igawk
 
 @node Anagram Program
-@subsection Finding Anagrams From A Dictionary
+@subsection Finding Anagrams from a Dictionary
 
 @cindex anagrams, finding
 An interesting programming challenge is to
@@ -25417,24 +25530,23 @@ word list (such as
 @file{/usr/share/dict/words} on many GNU/Linux systems).
 One word is an anagram of another if both words contain
 the same letters
-(for example, ``babbling'' and ``blabbing'').
+(e.g., ``babbling'' and ``blabbing'').
 
-Column 2, Problem C of Jon Bentley's @cite{Programming Pearls}, second
-edition, presents an elegant algorithm.  The idea is to give words that
+Column 2, Problem C, of Jon Bentley's @cite{Programming Pearls}, Second
+Edition, presents an elegant algorithm.  The idea is to give words that
 are anagrams a common signature, sort all the words together by their
-signature, and then print them.  Dr.@: Bentley observes that taking the
-letters in each word and sorting them produces that common signature.
+signatures, and then print them.  Dr.@: Bentley observes that taking the
+letters in each word and sorting them produces those common signatures.
 
 The following program uses arrays of arrays to bring together
 words with the same signature and array sorting to print the words
-in sorted order.
+in sorted order:
 
-@c STARTOFRANGE anagram
 @cindex @code{anagram.awk} program
 @example
 @c file eg/prog/anagram.awk
-# anagram.awk --- An implementation of the anagram finding algorithm
-#                 from Jon Bentley's "Programming Pearls", 2nd edition.
+# anagram.awk --- An implementation of the anagram-finding algorithm
+#                 from Jon Bentley's "Programming Pearls," 2nd edition.
 #                 Addison Wesley, 2000, ISBN 0-201-65788-0.
 #                 Column 2, Problem C, section 2.8, pp 18-20.
 @c endfile
@@ -25482,7 +25594,7 @@ sorts the letters, and then joins them back together:
 
 @example
 @c file eg/prog/anagram.awk
-# word2key --- split word apart into letters, sort, joining back together
+# word2key --- split word apart into letters, sort, and join back together
 
 function word2key(word,     a, i, n, result)
 @{
@@ -25499,7 +25611,7 @@ function word2key(word,     a, i, n, result)
 
 Finally, the @code{END} rule traverses the array
 and prints out the anagram lists.  It sends the output
-to the system @command{sort} command, since otherwise
+to the system @command{sort} command because otherwise
 the anagrams would appear in arbitrary order:
 
 @example
@@ -25527,21 +25639,20 @@ Here is some partial output when the program is run:
 @example
 $ @kbd{gawk -f anagram.awk /usr/share/dict/words | grep '^b'}
 @dots{}
-babbled blabbed 
-babbler blabber brabble 
-babblers blabbers brabbles 
-babbling blabbing 
-babbly blabby 
-babel bable 
-babels beslab 
-babery yabber 
+babbled blabbed
+babbler blabber brabble
+babblers blabbers brabbles
+babbling blabbing
+babbly blabby
+babel bable
+babels beslab
+babery yabber
 @dots{}
 @end example
 
-@c ENDOFRANGE anagram
 
 @node Signature Program
-@subsection And Now For Something Completely Different
+@subsection And Now for Something Completely Different
 
 @cindex signature program
 @cindex Brini, Davide
@@ -25581,28 +25692,28 @@ Subject: The GNU Awk User's Guide, Section 13.3.11
 From: "Chris Johansen" <johansen@main.nc.us>
 Message-ID: <op.v0iw6wlv7finx3@asusodin.thrudvang.lan>
 
-Arnold, you don't know me, but we have a tenuous connection.  My wife is  
+Arnold, you don't know me, but we have a tenuous connection.  My wife is
 Barbara A. Field, FAIA, GIT '65 (B. Arch.).
 
-I have had a couple of paper copies of "Effective Awk Programming" for  
-years, and now I'm going through a Kindle version of "The GNU Awk User's  
-Guide" again.  When I got to section 13.3.11, I reformatted and lightly  
+I have had a couple of paper copies of "Effective Awk Programming" for
+years, and now I'm going through a Kindle version of "The GNU Awk User's
+Guide" again.  When I got to section 13.3.11, I reformatted and lightly
 commented Davide Brin's signature script to understand its workings.
 
-It occurs to me that this might have pedagogical value as an example  
-(although imperfect) of the value of whitespace and comments, and a  
-starting point for that discussion.  It certainly helped _me_ understand  
-what's going on.  You are welcome to it, as-is or modified (subject to  
+It occurs to me that this might have pedagogical value as an example
+(although imperfect) of the value of whitespace and comments, and a
+starting point for that discussion.  It certainly helped _me_ understand
+what's going on.  You are welcome to it, as-is or modified (subject to
 Davide's constraints, of course, which I think I have met).
 
-If I were to include it in a future edition, I would put it at some  
-distance from section 13.3.11, say, as a note or an appendix, so as not to  
+If I were to include it in a future edition, I would put it at some
+distance from section 13.3.11, say, as a note or an appendix, so as not to
 be a "spoiler" to the puzzle.
 
 Best regards,
--- 
+--
 Chris Johansen {johansen at main dot nc dot us}
-  . . . collapsing the probability wave function, sending ripples of  
+  . . . collapsing the probability wave function, sending ripples of
 certainty through the space-time continuum.
 
 
@@ -25611,7 +25722,7 @@ certainty through the space-time continuum.
 # From "13.3.11 And Now For Something Completely Different"
 #   http://www.gnu.org/software/gawk/manual/html_node/Signature-Program.html#Signature-Program
 
-# Copyright © 2008 Davide Brini 
+# Copyright © 2008 Davide Brini
 
 # Copying and distribution of the code published in this page, with
 # or without modification, are permitted in any medium without
@@ -25678,12 +25789,13 @@ characters.  The ability to use @code{split()} with the empty string as
 the separator can considerably simplify such tasks.
 
 @item
-The library functions from @ref{Library Functions}, proved their
-usefulness for a number of real (if small) programs.
+The examples here demonstrate the usefulness of the library
+functions from @DBREF{Library Functions}
+for a number of real (if small) programs.
 
 @item
 Besides reinventing POSIX wheels, other programs solved a selection of
-interesting problems, such as finding duplicates words in text, printing
+interesting problems, such as finding duplicate words in text, printing
 mailing labels, and finding anagrams.
 
 @end itemize
@@ -25730,7 +25842,7 @@ Brian Kernighan suggests that
 ``an alternative approach to state machines is to just read
 the input into an array, then use indexing.  It's almost always
 easier code, and for most inputs where you would use this, just
-as fast.''  Rewrite the logic to follow this 
+as fast.''  Rewrite the logic to follow this
 suggestion.
 
 
@@ -25831,7 +25943,7 @@ the use of the external @command{sort} utility.
 @c EXCLUDE END
 
 @ifnotinfo
-@part @value{PART3}Moving Beyond Standard @command{awk} With @command{gawk}
+@part @value{PART3}Moving Beyond Standard @command{awk} with @command{gawk}
 @end ifnotinfo
 
 @ifdocbook
@@ -25840,27 +25952,25 @@ It contains the following chapters:
 
 @itemize @value{BULLET}
 @item
-@ref{Advanced Features}.
+@ref{Advanced Features}
 
 @item
-@ref{Internationalization}.
+@ref{Internationalization}
 
 @item
-@ref{Debugger}.
+@ref{Debugger}
 
 @item
-@ref{Arbitrary Precision Arithmetic}.
+@ref{Arbitrary Precision Arithmetic}
 
 @item
-@ref{Dynamic Extensions}.
+@ref{Dynamic Extensions}
 @end itemize
 @end ifdocbook
 
 @node Advanced Features
 @chapter Advanced Features of @command{gawk}
-@c STARTOFRANGE gawadv
 @cindex @command{gawk}, features, advanced
-@c STARTOFRANGE advgaw
 @cindex advanced features, @command{gawk}
 @ignore
 Contributed by: Peter Langston <pud!psl@bellcore.bellcore.com>
@@ -25881,18 +25991,18 @@ a violent psychopath who knows where you live.}
 This @value{CHAPTER} discusses advanced features in @command{gawk}.
 It's a bit of a ``grab bag'' of items that are otherwise unrelated
 to each other.
-First, a command-line option allows @command{gawk} to recognize
+First, we look at a command-line option that allows @command{gawk} to recognize
 nondecimal numbers in input data, not just in @command{awk}
 programs.
 Then, @command{gawk}'s special features for sorting arrays are presented.
 Next, two-way I/O, discussed briefly in earlier parts of this
 @value{DOCUMENT}, is described in full detail, along with the basics
-of TCP/IP networking.  Finally, @command{gawk}
+of TCP/IP networking.  Finally, we see how @command{gawk}
 can @dfn{profile} an @command{awk} program, making it possible to tune
 it for performance.
 
 @c FULLXREF ON
-A number of advanced features require separate @value{CHAPTER}s of their
+Additional advanced features are discussed in separate @value{CHAPTER}s of their
 own:
 
 @itemize @value{BULLET}
@@ -25986,7 +26096,8 @@ This option may disappear in a future version of @command{gawk}.
 @node Array Sorting
 @section Controlling Array Traversal and Array Sorting
 
-@command{gawk} lets you control the order in which a @samp{for (i in array)}
+@command{gawk} lets you control the order in which a
+@samp{for (@var{indx} in @var{array})}
 loop traverses an array.
 
 In addition, two built-in functions, @code{asort()} and @code{asorti()},
@@ -26002,7 +26113,7 @@ to order the elements during sorting.
 @node Controlling Array Traversal
 @subsection Controlling Array Traversal
 
-By default, the order in which a @samp{for (i in array)} loop
+By default, the order in which a @samp{for (@var{indx} in @var{array})} loop
 scans an array is not defined; it is generally based upon
 the internal implementation of arrays inside @command{awk}.
 
@@ -26011,7 +26122,7 @@ in a particular order that you, the programmer, choose.  @command{gawk}
 lets you do this.
 
 @DBREF{Controlling Scanning} describes how you can assign special,
-pre-defined values to @code{PROCINFO["sorted_in"]} in order to
+predefined values to @code{PROCINFO["sorted_in"]} in order to
 control the order in which @command{gawk} traverses an array
 during a @code{for} loop.
 
@@ -26031,23 +26142,23 @@ function comp_func(i1, v1, i2, v2)
 @}
 @end example
 
-Here, @var{i1} and @var{i2} are the indices, and @var{v1} and @var{v2}
+Here, @code{i1} and @code{i2} are the indices, and @code{v1} and @code{v2}
 are the corresponding values of the two elements being compared.
-Either @var{v1} or @var{v2}, or both, can be arrays if the array being
+Either @code{v1} or @code{v2}, or both, can be arrays if the array being
 traversed contains subarrays as values.
-(@xref{Arrays of Arrays}, for more information about subarrays.)
+(@DBXREF{Arrays of Arrays} for more information about subarrays.)
 The three possible return values are interpreted as follows:
 
 @table @code
 @item comp_func(i1, v1, i2, v2) < 0
-Index @var{i1} comes before index @var{i2} during loop traversal.
+Index @code{i1} comes before index @code{i2} during loop traversal.
 
 @item comp_func(i1, v1, i2, v2) == 0
-Indices @var{i1} and @var{i2}
-come together but the relative order with respect to each other is undefined.
+Indices @code{i1} and @code{i2}
+come together, but the relative order with respect to each other is undefined.
 
 @item comp_func(i1, v1, i2, v2) > 0
-Index @var{i1} comes after index @var{i2} during loop traversal.
+Index @code{i1} comes after index @code{i2} during loop traversal.
 @end table
 
 Our first comparison function can be used to scan an array in
@@ -26078,7 +26189,7 @@ function cmp_str_val(i1, v1, i2, v2)
 
 The third
 comparison function makes all numbers, and numeric strings without
-any leading or trailing spaces, come out first during loop traversal:  
+any leading or trailing spaces, come out first during loop traversal:
 
 @example
 function cmp_num_str_val(i1, v1, i2, v2,   n1, n2)
@@ -26086,10 +26197,10 @@ function cmp_num_str_val(i1, v1, i2, v2,   n1, n2)
      # numbers before string value comparison, ascending order
      n1 = v1 + 0
      n2 = v2 + 0
-     if (n1 == v1) 
+     if (n1 == v1)
          return (n2 == v2) ? (n1 - n2) : -1
      else if (n2 == v2)
-         return 1 
+         return 1
      return (v1 < v2) ? -1 : (v1 != v2)
 @}
 @end example
@@ -26104,7 +26215,7 @@ BEGIN @{
     data[10] = "one"
     data[100] = 100
     data[20] = "two"
-    
+
     f[1] = "cmp_num_idx"
     f[2] = "cmp_str_val"
     f[3] = "cmp_num_str_val"
@@ -26128,14 +26239,14 @@ $ @kbd{gawk -f compdemo.awk}
 @print{}     data[10] = one
 @print{}     data[20] = two
 @print{}     data[100] = 100
-@print{} 
+@print{}
 @print{} Sort function: cmp_str_val      @ii{Sort by element values as strings}
 @print{}     data[one] = 10
 @print{}     data[100] = 100             @ii{String 100 is less than string 20}
 @print{}     data[two] = 20
 @print{}     data[10] = one
 @print{}     data[20] = two
-@print{} 
+@print{}
 @print{} Sort function: cmp_num_str_val  @ii{Sort all numeric values before all strings}
 @print{}     data[one] = 10
 @print{}     data[two] = 20
@@ -26146,7 +26257,7 @@ $ @kbd{gawk -f compdemo.awk}
 
 Consider sorting the entries of a GNU/Linux system password file
 according to login name.  The following program sorts records
-by a specific field position and can be used for this purpose:   
+by a specific field position and can be used for this purpose:
 
 @example
 # passwd-sort.awk --- simple program to sort by field position
@@ -26192,7 +26303,7 @@ $ @kbd{gawk -v POS=1 -F: -f sort.awk /etc/passwd}
 
 The comparison should normally always return the same value when given a
 specific pair of array elements as its arguments.  If inconsistent
-results are returned then the order is undefined.  This behavior can be
+results are returned, then the order is undefined.  This behavior can be
 exploited to introduce random order into otherwise seemingly
 ordered data:
 
@@ -26204,11 +26315,11 @@ function cmp_randomize(i1, v1, i2, v2)
 @}
 @end example
 
-As mentioned above, the order of the indices is arbitrary if two
+As already mentioned, the order of the indices is arbitrary if two
 elements compare equal.  This is usually not a problem, but letting
 the tied elements come out in arbitrary order can be an issue, especially
 when comparing item values.  The partial ordering of the equal elements
-may change the next time the array is traversed, if other elements are added or
+may change the next time the array is traversed, if other elements are added to or
 removed from the array.  One way to resolve ties when comparing elements
 with otherwise equal values is to include the indices in the comparison
 rules.  Note that doing this may make the loop traversal less efficient,
@@ -26245,21 +26356,21 @@ When string comparisons are made during a sort, either for element
 values where one or both aren't numbers, or for element indices
 handled as strings, the value of @code{IGNORECASE}
 (@pxref{Built-in Variables}) controls whether
-the comparisons treat corresponding uppercase and lowercase letters as
+the comparisons treat corresponding upper- and lowercase letters as
 equivalent or distinct.
 
-Another point to keep in mind is that in the case of subarrays
+Another point to keep in mind is that in the case of subarrays,
 the element values can themselves be arrays; a production comparison
 function should use the @code{isarray()} function
-(@pxref{Type Functions}),
+(@pxref{Type Functions})
 to check for this, and choose a defined sorting order for subarrays.
 
 All sorting based on @code{PROCINFO["sorted_in"]}
 is disabled in POSIX mode,
-since the @code{PROCINFO} array is not special in that case.
+because the @code{PROCINFO} array is not special in that case.
 
 As a side note, sorting the array indices before traversing
-the array has been reported to add 15% to 20% overhead to the
+the array has been reported to add a 15% to 20% overhead to the
 execution time of @command{awk} programs. For this reason,
 sorted array traversal is not the default.
 
@@ -26277,8 +26388,8 @@ sorted array traversal is not the default.
 @cindex @code{asorti()} function (@command{gawk}), arrays@comma{} sorting
 @cindex sort function, arrays, sorting
 In most @command{awk} implementations, sorting an array requires writing
-a @code{sort()} function.  While this can be educational for exploring
-different sorting algorithms, usually that's not the point of the program.
+a @code{sort()} function.  This can be educational for exploring
+different sorting algorithms, but usually that's not the point of the program.
 @command{gawk} provides the built-in @code{asort()} and @code{asorti()}
 functions (@pxref{String Functions}) for sorting arrays.  For example:
 
@@ -26318,7 +26429,7 @@ However, the @code{source} array is not affected.
 Often, what's needed is to sort on the values of the @emph{indices}
 instead of the values of the elements.  To do that, use the
 @code{asorti()} function.  The interface and behavior are identical to
-that of @code{asort()}, except that the index values are used for sorting,
+that of @code{asort()}, except that the index values are used for sorting
 and become the values of the result array:
 
 @example
@@ -26353,8 +26464,8 @@ it chooses}, taking into account just the indices, just the values,
 or both.  This is extremely powerful.
 
 Once the array is sorted, @code{asort()} takes the @emph{values} in
-their final order, and uses them to fill in the result array, whereas
-@code{asorti()} takes the @emph{indices} in their final order, and uses
+their final order and uses them to fill in the result array, whereas
+@code{asorti()} takes the @emph{indices} in their final order and uses
 them to fill in the result array.
 
 @cindex reference counting, sorting arrays
@@ -26374,8 +26485,8 @@ Because @code{IGNORECASE} affects string comparisons, the value
 of @code{IGNORECASE} also affects sorting for both @code{asort()} and @code{asorti()}.
 Note also that the locale's sorting order does @emph{not}
 come into play; comparisons are based on character values only.@footnote{This
-is true because locale-based comparison occurs only when in POSIX
-compatibility mode, and since @code{asort()} and @code{asorti()} are
+is true because locale-based comparison occurs only when in
+POSIX-compatibility mode, and because @code{asort()} and @code{asorti()} are
 @command{gawk} extensions, they are not available in that case.}
 
 @node Two-way I/O
@@ -26451,7 +26562,7 @@ remain more difficult to use than two-way pipes.} @c 8/2014
 @cindex @command{csh} utility, @code{|&} operator, comparison with
 However, with @command{gawk}, it is possible to
 open a @emph{two-way} pipe to another process.  The second process is
-termed a @dfn{coprocess}, since it runs in parallel with @command{gawk}.
+termed a @dfn{coprocess}, as it runs in parallel with @command{gawk}.
 The two-way connection is created using the @samp{|&} operator
 (borrowed from the Korn shell, @command{ksh}):@footnote{This is very
 different from the same operator in the C shell and in Bash.}
@@ -26556,7 +26667,7 @@ like so:
 @example
 command = "sort -nr"           # command, save in convenience variable
 PROCINFO[command, "pty"] = 1   # update PROCINFO
-print @dots{} |& command       # start two-way pipe
+print @dots{} |& command           # start two-way pipe
 @dots{}
 @end example
 
@@ -26570,7 +26681,6 @@ using regular pipes.
 @section Using @command{gawk} for Network Programming
 @cindex advanced features, network programming
 @cindex networks, programming
-@c STARTOFRANGE tcpip
 @cindex TCP/IP
 @cindex @code{/inet/@dots{}} special files (@command{gawk})
 @cindex files, @code{/inet/@dots{}} (@command{gawk})
@@ -26611,7 +26721,7 @@ You can think of this as just a @emph{very long} two-way pipeline to
 a coprocess.
 The way @command{gawk} decides that you want to use TCP/IP networking is
 by recognizing special @value{FN}s that begin with one of @samp{/inet/},
-@samp{/inet4/} or @samp{/inet6/}.
+@samp{/inet4/}, or @samp{/inet6/}.
 
 The full syntax of the special @value{FN} is
 @file{/@var{net-type}/@var{protocol}/@var{local-port}/@var{remote-host}/@var{remote-port}}.
@@ -26640,7 +26750,7 @@ or @samp{http}, in which case @command{gawk} attempts to determine
 the predefined port number using the C @code{getaddrinfo()} function.
 
 @item remote-host
-The IP address or fully-qualified domain name of the Internet
+The IP address or fully qualified domain name of the Internet
 host to which you want to connect.
 
 @item remote-port
@@ -26652,7 +26762,7 @@ service name.
 @cindex @command{gawk}, @code{ERRNO} variable in
 @cindex @code{ERRNO} variable
 @quotation NOTE
-Failure in opening a two-way socket will result in a non-fatal error
+Failure in opening a two-way socket will result in a nonfatal error
 being returned to the calling code. The value of @code{ERRNO} indicates
 the error (@pxref{Auto-set}).
 @end quotation
@@ -26669,31 +26779,28 @@ BEGIN @{
 @end example
 
 This program reads the current date and time from the local system's
-TCP @samp{daytime} server.
+TCP @code{daytime} server.
 It then prints the results and closes the connection.
 
 Because this topic is extensive, the use of @command{gawk} for
 TCP/IP programming is documented separately.
 @ifinfo
 See
-@inforef{Top, , General Introduction, gawkinet, TCP/IP Internetworking with @command{gawk}},
+@inforef{Top, , General Introduction, gawkinet, @value{GAWKINETTITLE}},
 @end ifinfo
 @ifnotinfo
 See
 @uref{http://www.gnu.org/software/gawk/manual/gawkinet/,
-@cite{TCP/IP Internetworking with @command{gawk}}},
+@cite{@value{GAWKINETTITLE}}},
 which comes as part of the @command{gawk} distribution,
 @end ifnotinfo
 for a much more complete introduction and discussion, as well as
 extensive examples.
 
-@c ENDOFRANGE tcpip
 
 @node Profiling
 @section Profiling Your @command{awk} Programs
-@c STARTOFRANGE awkp
 @cindex @command{awk} programs, profiling
-@c STARTOFRANGE proawk
 @cindex profiling @command{awk} programs
 @cindex @code{awkprof.out} file
 @cindex files, @code{awkprof.out}
@@ -26714,12 +26821,12 @@ gawk --profile=myprog.prof -f myprog.awk data1 data2
 @end example
 
 @noindent
-In the above example, @command{gawk} places the profile in
+In the preceding example, @command{gawk} places the profile in
 @file{myprog.prof} instead of in @file{awkprof.out}.
 
-Here is a sample session showing a simple @command{awk} program, its input data, and the
-results from running @command{gawk} with the @option{--profile} option.
-First, the @command{awk} program:
+Here is a sample session showing a simple @command{awk} program,
+its input data, and the results from running @command{gawk} with the
+@option{--profile} option.  First, the @command{awk} program:
 
 @example
 BEGIN @{ print "First BEGIN rule" @}
@@ -26760,9 +26867,9 @@ junk
 @end example
 
 Here is the @file{awkprof.out} that results from running the
-@command{gawk} profiler on this program and data. (This example also
+@command{gawk} profiler on this program and data (this example also
 illustrates that @command{awk} programmers sometimes get up very early
-in the morning to work.)
+in the morning to work):
 
 @cindex @code{BEGIN} pattern, and profiling
 @cindex @code{END} pattern, and profiling
@@ -26822,8 +26929,8 @@ They are as follows:
 @item
 The program is printed in the order @code{BEGIN} rules,
 @code{BEGINFILE} rules,
-pattern/action rules,
-@code{ENDFILE} rules, @code{END} rules and functions, listed
+pattern--action rules,
+@code{ENDFILE} rules, @code{END} rules, and functions, listed
 alphabetically.
 Multiple @code{BEGIN} and @code{END} rules retain their
 separate identities, as do
@@ -26831,7 +26938,7 @@ multiple @code{BEGINFILE} and @code{ENDFILE} rules.
 
 @cindex patterns, counts, in a profile
 @item
-Pattern-action rules have two counts.
+Pattern--action rules have two counts.
 The first count, to the left of the rule, shows how many times
 the rule's pattern was @emph{tested}.
 The second count, to the right of the rule's opening left brace
@@ -26877,7 +26984,7 @@ the body of an @code{if}, @code{else}, or loop is only a single statement.
 @item
 Parentheses are used only where needed, as indicated by the structure
 of the program and the precedence rules.
-For example, @samp{(3 + 5) * 4} means add three plus five, then multiply
+For example, @samp{(3 + 5) * 4} means add three and five, then multiply
 the total by four.  However, @samp{3 + 5 * 4} has no parentheses, and
 means @samp{3 + (5 * 4)}.
 
@@ -26898,13 +27005,13 @@ the target of a redirection isn't a scalar, it gets parenthesized.
 @command{gawk} supplies leading comments in
 front of the @code{BEGIN} and @code{END} rules,
 the @code{BEGINFILE} and @code{ENDFILE} rules,
-the pattern/action rules, and the functions.
+the pattern--action rules, and the functions.
 
 @end itemize
 
 The profiled version of your program may not look exactly like what you
 typed when you wrote it.  This is because @command{gawk} creates the
-profiled version by ``pretty printing'' its internal representation of
+profiled version by ``pretty-printing'' its internal representation of
 the program.  The advantage to this is that @command{gawk} can produce
 a standard representation.
 Also, things such as:
@@ -26987,16 +27094,16 @@ If you use the @code{HUP} signal instead of the @code{USR1} signal,
 @cindex @code{SIGQUIT} signal (MS-Windows)
 @cindex signals, @code{QUIT}/@code{SIGQUIT} (MS-Windows)
 When @command{gawk} runs on MS-Windows systems, it uses the
-@code{INT} and @code{QUIT} signals for producing the profile and, in
+@code{INT} and @code{QUIT} signals for producing the profile, and in
 the case of the @code{INT} signal, @command{gawk} exits.  This is
 because these systems don't support the @command{kill} command, so the
 only signals you can deliver to a program are those generated by the
 keyboard.  The @code{INT} signal is generated by the
-@kbd{Ctrl-@key{C}} or @kbd{Ctrl-@key{BREAK}} key, while the
-@code{QUIT} signal is generated by the @kbd{Ctrl-@key{\}} key.
+@kbd{Ctrl-c} or @kbd{Ctrl-BREAK} key, while the
+@code{QUIT} signal is generated by the @kbd{Ctrl-\} key.
 
 Finally, @command{gawk} also accepts another option, @option{--pretty-print}.
-When called this way, @command{gawk} ``pretty prints'' the program into
+When called this way, @command{gawk} ``pretty-prints'' the program into
 @file{awkprof.out}, without any execution counts.
 
 @quotation NOTE
@@ -27020,9 +27127,6 @@ that the profiling output does. This makes it easy to pretty-print your
 code once development is completed, and then use the result as the final
 version of your program.
 
-@c ENDOFRANGE awkp
-@c ENDOFRANGE proawk
-
 @node Advanced Features Summary
 @section Summary
 
@@ -27053,7 +27157,7 @@ optionally, close off one side of the two-way communications.
 
 @item
 By using special @value{FN}s with the @samp{|&} operator, you can open a
-TCP/IP (or UDP/IP) connection to remote hosts in the Internet. @command{gawk}
+TCP/IP (or UDP/IP) connection to remote hosts on the Internet. @command{gawk}
 supports both IPv4 and IPv6.
 
 @item
@@ -27063,13 +27167,11 @@ you tune them more easily.  Sending the @code{USR1} signal while profiling cause
 @command{gawk} to dump the profile and keep going, including a function call stack.
 
 @item
-You can also just ``pretty print'' the program. This currently also runs
+You can also just ``pretty-print'' the program. This currently also runs
 the program, but that will change in the next major release.
 
 @end itemize
 
-@c ENDOFRANGE advgaw
-@c ENDOFRANGE gawadv
 
 @node Internationalization
 @chapter Internationalization with @command{gawk}
@@ -27082,7 +27184,6 @@ countries, they were able to sell more systems.
 As a result, internationalization and localization
 of programs and software systems became a common practice.
 
-@c STARTOFRANGE inloc
 @cindex internationalization, localization
 @cindex @command{gawk}, internationalization and, See internationalization
 @cindex internationalization, localization, @command{gawk} and
@@ -27115,7 +27216,7 @@ a requirement.
 @cindex localization
 @dfn{Internationalization} means writing (or modifying) a program once,
 in such a way that it can use multiple languages without requiring
-further source-code changes.
+further source code changes.
 @dfn{Localization} means providing the data necessary for an
 internationalized program to work in a particular language.
 Most typically, these terms refer to features such as the language
@@ -27127,11 +27228,10 @@ monetary values are printed and read.
 @section GNU @command{gettext}
 
 @cindex internationalizing a program
-@c STARTOFRANGE gettex
 @cindex @command{gettext} library
 @command{gawk} uses GNU @command{gettext} to provide its internationalization
 features.
-The facilities in GNU @command{gettext} focus on messages; strings printed
+The facilities in GNU @command{gettext} focus on messages: strings printed
 by a program, either directly or via formatting with @code{printf} or
 @code{sprintf()}.@footnote{For some operating systems, the @command{gawk}
 port doesn't support GNU @command{gettext}.
@@ -27152,8 +27252,7 @@ following steps, in this order:
 
 @enumerate
 @item
-The programmer goes
-through the source for all of @command{guide}'s components
+The programmer reviews the source for all of @command{guide}'s components
 and marks each string that is a candidate for translation.
 For example, @code{"`-F': option required"} is a good candidate for translation.
 A table with strings of option names is not (e.g., @command{gawk}'s
@@ -27180,7 +27279,6 @@ lookup of the translations.
 
 @cindex @code{.po} files
 @cindex files, @code{.po}
-@c STARTOFRANGE portobfi
 @cindex portable object files
 @cindex files, portable object
 @item
@@ -27192,7 +27290,6 @@ For example, there might be a @file{fr.po} for a French translation.
 @cindex @code{.gmo} files
 @cindex files, @code{.gmo}
 @cindex message object files
-@c STARTOFRANGE portmsgfi
 @cindex files, message object
 @item
 Each language's @file{.po} file is converted into a binary
@@ -27273,8 +27370,8 @@ if necessary.  (It is almost never necessary to supply a different category.)
 @cindex sorting characters in different languages
 @cindex @code{LC_COLLATE} locale category
 @item LC_COLLATE
-Text-collation information; i.e., how different characters
-and/or groups of characters sort in a given language.
+Text-collation information (i.e., how different characters
+and/or groups of characters sort in a given language).
 
 @cindex @code{LC_CTYPE} locale category
 @item LC_CTYPE
@@ -27320,14 +27417,12 @@ before or after the day in a date, local month abbreviations, and so on.
 @item LC_ALL
 All of the above.  (Not too useful in the context of @command{gettext}.)
 @end table
-@c ENDOFRANGE gettex
 
 @node Programmer i18n
 @section Internationalizing @command{awk} Programs
-@c STARTOFRANGE inap
 @cindex @command{awk} programs, internationalizing
 
-@command{gawk} provides the following variables and functions for
+@command{gawk} provides the following variables for
 internationalization:
 
 @table @code
@@ -27343,7 +27438,12 @@ value is @code{"messages"}.
 String constants marked with a leading underscore
 are candidates for translation at runtime.
 String constants without a leading underscore are not translated.
+@end table
 
+@command{gawk} provides the following functions for
+internationalization:
+
+@table @code
 @cindexgawkfunc{dcgettext}
 @item @code{dcgettext(@var{string}} [@code{,} @var{domain} [@code{,} @var{category}]]@code{)}
 Return the translation of @var{string} in
@@ -27400,15 +27500,7 @@ If @var{directory} is the null string (@code{""}), then
 given @var{domain}.
 @end table
 
-To use these facilities in your @command{awk} program, follow the steps
-outlined in
-@ifnotinfo
-the previous @value{SECTION},
-@end ifnotinfo
-@ifinfo
-@ref{Explaining gettext},
-@end ifinfo
-like so:
+To use these facilities in your @command{awk} program, follow these steps:
 
 @enumerate
 @cindex @code{BEGIN} pattern, @code{TEXTDOMAIN} variable and
@@ -27493,7 +27585,7 @@ BEGIN @{
 
 @end enumerate
 
-@xref{I18N Example},
+@DBXREF{I18N Example}
 for an example program showing the steps to create
 and use translations from @command{awk}.
 
@@ -27554,11 +27646,9 @@ second argument to @code{dcngettext()}.@footnote{The
 You should distribute the generated @file{.pot} file with
 your @command{awk} program; translators will eventually use it
 to provide you translations that you can also then distribute.
-@xref{I18N Example},
+@DBXREF{I18N Example}
 for the full list of steps to go through to create and test
 translations for @command{guide}.
-@c ENDOFRANGE portobfi
-@c ENDOFRANGE portmsgfi
 
 @node Printf Ordering
 @subsection Rearranging @code{printf} Arguments
@@ -27682,7 +27772,7 @@ change:
 @cindex @code{TEXTDOMAIN} variable, portability and
 @item
 Assignments to @code{TEXTDOMAIN} won't have any effect,
-since @code{TEXTDOMAIN} is not special in other @command{awk} implementations.
+because @code{TEXTDOMAIN} is not special in other @command{awk} implementations.
 
 @item
 Non-GNU versions of @command{awk} treat marked strings
@@ -27693,7 +27783,7 @@ the null string (@code{""}) as its value, leaving the original string constant a
 the result.
 
 @item
-By defining ``dummy'' functions to replace @code{dcgettext()}, @code{dcngettext()}
+By defining ``dummy'' functions to replace @code{dcgettext()}, @code{dcngettext()},
 and @code{bindtextdomain()}, the @command{awk} program can be made to run, but
 all the messages are output in the original language.
 For example:
@@ -27730,11 +27820,10 @@ enough arguments are supplied in the function call.  Many versions of
 underlying C library version of @code{sprintf()}, but only one format and
 argument at a time.  What happens if a positional specification is
 used is anybody's guess.
-However, since the positional specifications are primarily for use in
-@emph{translated} format strings, and since non-GNU @command{awk}s never
+However, because the positional specifications are primarily for use in
+@emph{translated} format strings, and because non-GNU @command{awk}s never
 retrieve the translated string, this should not be a problem in practice.
 @end itemize
-@c ENDOFRANGE inap
 
 @node I18N Example
 @section A Simple Internationalization Example
@@ -27794,7 +27883,7 @@ called ``Hippy.'' Ah, well.}
 
 @example
 @group
-$ cp guide.pot guide-mellow.po
+$ @kbd{cp guide.pot guide-mellow.po}
 @var{Add translations to} guide-mellow.po @dots{}
 @end group
 @end example
@@ -27820,7 +27909,7 @@ msgstr "Like, the scoop is"
 The next step is to make the directory to hold the binary message object
 file and then to create the @file{guide.mo} file.
 We pretend that our file is to be used in the @code{en_US.UTF-8} locale,
-since we have to use a locale name known to the C @command{gettext} routines.
+because we have to use a locale name known to the C @command{gettext} routines.
 The directory layout shown here is standard for GNU @command{gettext} on
 GNU/Linux systems.  Other versions of @command{gettext} may use a different
 layout:
@@ -27857,7 +27946,7 @@ $ @kbd{gawk -f guide.awk}
 @print{} Pardon me, Zaphod who?
 @end example
 
-If the three replacement functions for @code{dcgettext()}, @code{dcngettext()}
+If the three replacement functions for @code{dcgettext()}, @code{dcngettext()},
 and @code{bindtextdomain()}
 (@pxref{I18N Portability})
 are in a file named @file{libintl.awk},
@@ -27878,15 +27967,15 @@ using the GNU @command{gettext} package.
 (GNU @command{gettext} is described in
 complete detail in
 @ifinfo
-@inforef{Top, , GNU @command{gettext} utilities, gettext, GNU gettext tools}.)
+@inforef{Top, , GNU @command{gettext} utilities, gettext, GNU @command{gettext} utilities}.)
 @end ifinfo
 @ifnotinfo
 @uref{http://www.gnu.org/software/gettext/manual/,
-@cite{GNU gettext tools}}.)
+@cite{GNU @command{gettext} utilities}}.)
 @end ifnotinfo
 As of this writing, the latest version of GNU @command{gettext} is
-@uref{ftp://ftp.gnu.org/gnu/gettext/gettext-0.19.2.tar.gz,
-@value{PVERSION} 0.19.2}.
+@uref{ftp://ftp.gnu.org/gnu/gettext/gettext-0.19.4.tar.gz,
+@value{PVERSION} 0.19.4}.
 
 If a translation of @command{gawk}'s messages exists,
 then @command{gawk} produces usage messages, warnings,
@@ -27898,7 +27987,7 @@ and fatal errors in the local language.
 @itemize @value{BULLET}
 @item
 Internationalization means writing a program such that it can use multiple
-languages without requiring source-code changes.  Localization means
+languages without requiring source code changes.  Localization means
 providing the data necessary for an internationalized program to work
 in a particular language.
 
@@ -27915,9 +28004,9 @@ file, and the @file{.po} files are compiled into @file{.gmo} files for
 use at runtime.
 
 @item
-You can use position specifications with @code{sprintf()} and
+You can use positional specifications with @code{sprintf()} and
 @code{printf} to rearrange the placement of argument values in formatted
-strings and output. This is useful for the translations of format
+strings and output. This is useful for the translation of format
 control strings.
 
 @item
@@ -27930,7 +28019,6 @@ a number of translations for its messages.
 
 @end itemize
 
-@c ENDOFRANGE inloc
 
 @node Debugger
 @chapter Debugging @command{awk} Programs
@@ -27959,7 +28047,7 @@ how to use @command{gawk} for debugging your program is easy.
 @end menu
 
 @node Debugging
-@section Introduction to The @command{gawk} Debugger
+@section Introduction to the @command{gawk} Debugger
 
 This @value{SECTION} introduces debugging in general and begins
 the discussion of debugging in @command{gawk}.
@@ -27974,11 +28062,10 @@ the discussion of debugging in @command{gawk}.
 @subsection Debugging in General
 
 (If you have used debuggers in other languages, you may want to skip
-ahead to the next section on the specific features of the @command{gawk}
-debugger.)
+ahead to @ref{Awk Debugging}.)
 
-Of course, a debugging program cannot remove bugs for you, since it has
-no way of knowing what you or your users consider a ``bug'' and what is a
+Of course, a debugging program cannot remove bugs for you, because it has
+no way of knowing what you or your users consider a ``bug'' versus a
 ``feature.''  (Sometimes, we humans have a hard time with this ourselves.)
 In that case, what can you expect from such a tool?  The answer to that
 depends on the language being debugged, but in general, you can expect at
@@ -27999,7 +28086,7 @@ having to change your source files.
 @item
 The chance to see the values of data in the program at any point in
 execution, and also to change that data on the fly, to see how that
-affects what happens afterwards.  (This often includes the ability
+affects what happens afterward.  (This often includes the ability
 to look at internal data structures besides the variables you actually
 defined in your code.)
 
@@ -28019,11 +28106,11 @@ functional program that you or someone else wrote).
 Before diving in to the details, we need to introduce several
 important concepts that apply to just about all debuggers.
 The following list defines terms used throughout the rest of
-this @value{CHAPTER}.
+this @value{CHAPTER}:
 
 @table @dfn
 @cindex stack frame
-@item Stack Frame
+@item Stack frame
 Programs generally call functions during the course of their execution.
 One function can call another, or a function can call itself (recursion).
 You can view the chain of called functions (main program calls A, which
@@ -28058,7 +28145,7 @@ as many breakpoints as you like.
 A watchpoint is similar to a breakpoint.  The difference is that
 breakpoints are oriented around the code: stop when a certain point in the
 code is reached.  A watchpoint, however, specifies that program execution
-should stop when a @emph{data value} is changed.  This is useful, since
+should stop when a @emph{data value} is changed.  This is useful, as
 sometimes it happens that a variable receives an erroneous value, and it's
 hard to track down where this happens just by looking at the code.
 By using a watchpoint, you can stop whenever a variable is assigned to,
@@ -28066,26 +28153,26 @@ and usually find the errant code quite quickly.
 @end table
 
 @node Awk Debugging
-@subsection Awk Debugging
+@subsection @command{awk} Debugging
 
 Debugging an @command{awk} program has some specific aspects that are
-not shared with other programming languages.
+not shared with programs written in other languages.
 
 First of all, the fact that @command{awk} programs usually take input
-line-by-line from a file or files and operate on those lines using specific
+line by line from a file or files and operate on those lines using specific
 rules makes it especially useful to organize viewing the execution of
 the program in terms of these rules.  As we will see, each @command{awk}
 rule is treated almost like a function call, with its own specific block
 of instructions.
 
-In addition, since @command{awk} is by design a very concise language,
+In addition, because @command{awk} is by design a very concise language,
 it is easy to lose sight of everything that is going on ``inside''
 each line of @command{awk} code.  The debugger provides the opportunity
 to look at the individual primitive instructions carried out
 by the higher-level @command{awk} commands.
 
 @node Sample Debugging Session
-@section Sample Debugging Session
+@section Sample @command{gawk} Debugging Session
 @cindex sample debugging session
 
 In order to illustrate the use of @command{gawk} as a debugger, let's look at a sample
@@ -28104,8 +28191,8 @@ as our example.
 @cindex debugger, how to start
 
 Starting the debugger is almost exactly like running @command{gawk} normally,
-except you have to pass an additional option @option{--debug}, or the
-corresponding short option @option{-D}.  The file(s) containing the
+except you have to pass an additional option, @option{--debug}, or the
+corresponding short option, @option{-D}.  The file(s) containing the
 program and any supporting code are given on the command line as arguments
 to one or more @option{-f} options. (@command{gawk} is not designed
 to debug command-line programs, only programs contained in files.)
@@ -28118,7 +28205,7 @@ $ @kbd{gawk -D -f getopt.awk -f join.awk -f uniq.awk -1 inputfile}
 @noindent
 where both @file{getopt.awk} and @file{uniq.awk} are in @env{$AWKPATH}.
 (Experienced users of GDB or similar debuggers should note that
-this syntax is slightly different from what they are used to.
+this syntax is slightly different from what you are used to.
 With the @command{gawk} debugger, you give the arguments for running the program
 in the command line to the debugger rather than as part of the @code{run}
 command at the debugger prompt.)
@@ -28205,7 +28292,7 @@ gawk> @kbd{bt}
 @end example
 
 This tells us that @code{are_equal()} was called by the main program at
-line 88 of @file{uniq.awk}.  (This is not a big surprise, since this
+line 88 of @file{uniq.awk}.  (This is not a big surprise, because this
 is the only call to @code{are_equal()} in the program, but in more complex
 programs, knowing who called a function and with what parameters can be
 the key to finding the source of the problem.)
@@ -28222,7 +28309,7 @@ gawk> @kbd{p n}
 @end example
 
 @noindent
-In this case, @code{n} is an uninitialized local variable, since the
+In this case, @code{n} is an uninitialized local variable, because the
 function was called without arguments (@pxref{Function Calls}).
 
 A more useful variable to display might be the current record:
@@ -28233,8 +28320,8 @@ gawk> @kbd{p $0}
 @end example
 
 @noindent
-This might be a bit puzzling at first since this is the second line of
-our test input above.  Let's look at @code{NR}:
+This might be a bit puzzling at first, as this is the second line of
+our test input.  Let's look at @code{NR}:
 
 @example
 gawk> @kbd{p NR}
@@ -28272,10 +28359,10 @@ gawk> @kbd{n}
 @end example
 
 This tells us that @command{gawk} is now ready to execute line 66, which
-decides whether to give the lines the special ``field skipping'' treatment
+decides whether to give the lines the special ``field-skipping'' treatment
 indicated by the @option{-1} command-line option.  (Notice that we skipped
-from where we were before at line 63 to here, since the condition in line 63
-@samp{if (fcount == 0 && charcount == 0)} was false.)
+from where we were before, at line 63, to here, because the condition
+in line 63, @samp{if (fcount == 0 && charcount == 0)}, was false.)
 
 Continuing to step, we now get to the splitting of the current and
 last records:
@@ -28304,7 +28391,7 @@ gawk> @kbd{p n m alast aline}
 
 This is kind of disappointing, though.  All we found out is that there
 are five elements in @code{alast}; @code{m} and @code{aline} don't have
-values since we are at line 68 but haven't executed it yet.
+values because we are at line 68 but haven't executed it yet.
 This information is useful enough (we now know that
 none of the words were accidentally left out), but what if we want to see
 inside the array?
@@ -28349,7 +28436,7 @@ gawk> @kbd{n}
 
 Well, here we are at our error (sorry to spoil the suspense).  What we
 had in mind was to join the fields starting from the second one to make
-the virtual record to compare, and if the first field was numbered zero,
+the virtual record to compare, and if the first field were numbered zero,
 this would work.  Let's look at what we've got:
 
 @example
@@ -28358,7 +28445,7 @@ gawk> @kbd{p cline clast}
 @print{} clast = "awk is a wonderful program!"
 @end example
 
-Hey, those look pretty familiar!  They're just our original, unaltered,
+Hey, those look pretty familiar!  They're just our original, unaltered
 input records.  A little thinking (the human brain is still the best
 debugging tool), and we realize that we were off by one!
 
@@ -28408,13 +28495,14 @@ Miscellaneous
 @end itemize
 
 Each of these are discussed in the following subsections.
-In the following descriptions, commands which may be abbreviated
+In the following descriptions, commands that may be abbreviated
 show the abbreviation on a second description line.
 A debugger command name may also be truncated if that partial
 name is unambiguous. The debugger has the built-in capability to
-automatically repeat the previous command just by hitting @key{Enter}.
-This works for the commands @code{list}, @code{next}, @code{nexti}, @code{step}, @code{stepi}
-and @code{continue} executed without any argument.
+automatically repeat the previous command just by hitting @kbd{Enter}.
+This works for the commands @code{list}, @code{next}, @code{nexti},
+@code{step}, @code{stepi}, and @code{continue} executed without any
+argument.
 
 @menu
 * Breakpoint Control::          Control of Breakpoints.
@@ -28429,9 +28517,9 @@ and @code{continue} executed without any argument.
 @node Breakpoint Control
 @subsection Control of Breakpoints
 
-As we saw above, the first thing you probably want to do in a debugging
-session is to get your breakpoints set up, since otherwise your program
-will just run as if it was not under the debugger.  The commands for
+As we saw earlier, the first thing you probably want to do in a debugging
+session is to get your breakpoints set up, because your program
+will otherwise just run as if it was not under the debugger.  The commands for
 controlling breakpoints are:
 
 @table @asis
@@ -28461,7 +28549,7 @@ Set a breakpoint at entry to (the first instruction of)
 function @var{function}.
 @end table
 
-Each breakpoint is assigned a number which can be used to delete it from
+Each breakpoint is assigned a number that can be used to delete it from
 the breakpoint list using the @code{delete} command.
 
 With a breakpoint, you may also supply a condition.  This is an
@@ -28502,8 +28590,8 @@ that the debugger evaluates
 whenever the breakpoint or watchpoint is reached. If the condition is true, then
 the debugger stops execution and prompts for a command. Otherwise,
 the debugger continues executing the program. If the condition expression is
-not specified, any existing condition is removed; i.e., the breakpoint or
-watchpoint is made unconditional. 
+not specified, any existing condition is removed (i.e., the breakpoint or
+watchpoint is made unconditional).
 
 @cindex debugger commands, @code{d} (@code{delete})
 @cindex debugger commands, @code{delete}
@@ -28513,7 +28601,7 @@ watchpoint is made unconditional.
 @cindex breakpoint, delete by number
 @item @code{delete} [@var{n1 n2} @dots{}] [@var{n}--@var{m}]
 @itemx @code{d} [@var{n1 n2} @dots{}] [@var{n}--@var{m}]
-Delete specified breakpoints or a range of breakpoints. Deletes
+Delete specified breakpoints or a range of breakpoints. Delete
 all defined breakpoints if no argument is supplied.
 
 @cindex debugger commands, @code{disable}
@@ -28522,7 +28610,7 @@ all defined breakpoints if no argument is supplied.
 @cindex breakpoint, how to disable or enable
 @item @code{disable} [@var{n1 n2} @dots{} | @var{n}--@var{m}]
 Disable specified breakpoints or a range of breakpoints. Without
-any argument, disables all breakpoints.
+any argument, disable all breakpoints.
 
 @cindex debugger commands, @code{e} (@code{enable})
 @cindex debugger commands, @code{enable}
@@ -28532,18 +28620,18 @@ any argument, disables all breakpoints.
 @item @code{enable} [@code{del} | @code{once}] [@var{n1 n2} @dots{}] [@var{n}--@var{m}]
 @itemx @code{e} [@code{del} | @code{once}] [@var{n1 n2} @dots{}] [@var{n}--@var{m}]
 Enable specified breakpoints or a range of breakpoints. Without
-any argument, enables all breakpoints.
-Optionally, you can specify how to enable the breakpoint:
+any argument, enable all breakpoints.
+Optionally, you can specify how to enable the breakpoints:
 
 @c nested table
 @table @code
 @item del
-Enable the breakpoint(s) temporarily, then delete it when
-the program stops at the breakpoint.
+Enable the breakpoints temporarily, then delete each one when
+the program stops at it.
 
 @item once
-Enable the breakpoint(s) temporarily, then disable it when
-the program stops at the breakpoint.
+Enable the breakpoints temporarily, then disable each one when
+the program stops at it.
 @end table
 
 @cindex debugger commands, @code{ignore}
@@ -28611,7 +28699,7 @@ gawk>
 @item @code{continue} [@var{count}]
 @itemx @code{c} [@var{count}]
 Resume program execution. If continued from a breakpoint and @var{count} is
-specified, ignores the breakpoint at that location the next @var{count} times
+specified, ignore the breakpoint at that location the next @var{count} times
 before stopping.
 
 @cindex debugger commands, @code{finish}
@@ -28644,7 +28732,7 @@ Execute one (or @var{count}) instruction(s), stepping over function calls.
 @item @code{return} [@var{value}]
 Cancel execution of a function call. If @var{value} (either a string or a
 number) is specified, it is used as the function's return value. If used in a
-frame other than the innermost one (the currently executing function, i.e.,
+frame other than the innermost one (the currently executing function; i.e.,
 frame number 0), discard all inner frames in addition to the selected one,
 and the caller of that frame becomes the innermost frame.
 
@@ -28665,7 +28753,7 @@ automatic display variables, and debugger options.
 @item @code{step} [@var{count}]
 @itemx @code{s} [@var{count}]
 Continue execution until control reaches a different source line in the
-current stack frame. @code{step} steps inside any function called within
+current stack frame, stepping inside any function called within
 the line.  If the argument @var{count} is supplied, steps that many times before
 stopping, unless it encounters a breakpoint or watchpoint.
 
@@ -28710,7 +28798,7 @@ gawk> @kbd{display x}
 @end example
 
 @noindent
-displays the assigned item number, the variable name and its current value.
+This displays the assigned item number, the variable name, and its current value.
 If the display variable refers to a function parameter, it is silently
 deleted from the list as soon as the execution reaches a context where
 no such variable of the given name exists.
@@ -28778,7 +28866,7 @@ or field.
 String values must be enclosed between double quotes (@code{"}@dots{}@code{"}).
 
 You can also set special @command{awk} variables, such as @code{FS},
-@code{NF}, @code{NR}, etc.
+@code{NF}, @code{NR}, and so on.
 
 @cindex debugger commands, @code{w} (@code{watch})
 @cindex debugger commands, @code{watch}
@@ -28790,7 +28878,7 @@ You can also set special @command{awk} variables, such as @code{FS},
 Add variable @var{var} (or field @code{$@var{n}}) to the watch list.
 The debugger then stops whenever
 the value of the variable or field changes. Each watched item is assigned a
-number which can be used to delete it from the watch list using the
+number that can be used to delete it from the watch list using the
 @code{unwatch} command.
 
 With a watchpoint, you may also supply a condition.  This is an
@@ -28818,11 +28906,11 @@ watch list.
 @node Execution Stack
 @subsection Working with the Stack
 
-Whenever you run a program which contains any function calls,
+Whenever you run a program that contains any function calls,
 @command{gawk} maintains a stack of all of the function calls leading up
 to where the program is right now.  You can see how you got to where you are,
 and also move around in the stack to see what the state of things was in the
-functions which called the one you are in.  The commands for doing this are:
+functions that called the one you are in.  The commands for doing this are:
 
 @table @asis
 @cindex debugger commands, @code{bt} (@code{backtrace})
@@ -28841,7 +28929,7 @@ Print a backtrace of all function calls (stack frames), or innermost @var{count}
 frames if @var{count} > 0. Print the outermost @var{count} frames if
 @var{count} < 0.  The backtrace displays the name and arguments to each
 function, the source @value{FN}, and the line number.
-The alias @code{where} for @code{backtrace} is provided for long-time
+The alias @code{where} for @code{backtrace} is provided for longtime
 GDB users who may be used to that command.
 
 @cindex debugger commands, @code{down}
@@ -28857,8 +28945,8 @@ Then select and print the frame.
 @item @code{frame} [@var{n}]
 @itemx @code{f} [@var{n}]
 Select and print stack frame @var{n}.  Frame 0 is the currently executing,
-or @dfn{innermost}, frame (function call), frame 1 is the frame that
-called the innermost one. The highest numbered frame is the one for the
+or @dfn{innermost}, frame (function call); frame 1 is the frame that
+called the innermost one. The highest-numbered frame is the one for the
 main program.  The printed information consists of the frame number,
 function and argument names, source file, and the source line.
 
@@ -28870,11 +28958,11 @@ Then select and print the frame.
 @end table
 
 @node Debugger Info
-@subsection Obtaining Information about the Program and the Debugger State
+@subsection Obtaining Information About the Program and the Debugger State
 
 Besides looking at the values of variables, there is often a need to get
 other sorts of information about the state of your program and of the
-debugging environment itself.  The @command{gawk} debugger has one command which
+debugging environment itself.  The @command{gawk} debugger has one command that
 provides this information, appropriately called @code{info}.  @code{info}
 is used with one of a number of arguments that tell it exactly what
 you want to know:
@@ -28962,12 +29050,12 @@ The available options are:
 @table @asis
 @item @code{history_size}
 @cindex debugger history size
-The maximum number of lines to keep in the history file @file{./.gawk_history}.
-The default is 100.
+Set the maximum number of lines to keep in the history file
+@file{./.gawk_history}.  The default is 100.
 
 @item @code{listsize}
 @cindex debugger default list amount
-The number of lines that @code{list} prints. The default is 15.
+Specify the number of lines that @code{list} prints. The default is 15.
 
 @item @code{outfile}
 @cindex redirect @command{gawk} output, in debugger
@@ -28977,7 +29065,7 @@ standard output.
 
 @item @code{prompt}
 @cindex debugger prompt
-The debugger prompt. The default is @samp{@w{gawk> }}.
+Change the debugger prompt. The default is @samp{@w{gawk> }}.
 
 @item @code{save_history} [@code{on} | @code{off}]
 @cindex debugger history file
@@ -28988,7 +29076,7 @@ The default is @code{on}.
 @cindex save debugger options
 Save current options to file @file{./.gawkrc} upon exit.
 The default is @code{on}.
-Options are read back in to the next session upon startup.
+Options are read back into the next session upon startup.
 
 @item @code{trace} [@code{on} | @code{off}]
 @cindex instruction tracing, in debugger
@@ -29011,7 +29099,7 @@ command in the file. Also, the list of commands may include additional
 @code{source} commands; however, the @command{gawk} debugger will not source the
 same file more than once in order to avoid infinite recursion.
 
-In addition to, or instead of the @code{source} command, you can use
+In addition to, or instead of, the @code{source} command, you can use
 the @option{-D @var{file}} or @option{--debug=@var{file}} command-line
 options to execute commands from a file non-interactively
 (@pxref{Options}).
@@ -29020,16 +29108,16 @@ options to execute commands from a file non-interactively
 @node Miscellaneous Debugger Commands
 @subsection Miscellaneous Commands
 
-There are a few more commands which do not fit into the
+There are a few more commands that do not fit into the
 previous categories, as follows:
 
 @table @asis
 @cindex debugger commands, @code{dump}
 @cindex @code{dump} debugger command
 @item @code{dump} [@var{filename}]
-Dump bytecode of the program to standard output or to the file
+Dump byte code of the program to standard output or to the file
 named in @var{filename}.  This prints a representation of the internal
-instructions which @command{gawk} executes to implement the @command{awk}
+instructions that @command{gawk} executes to implement the @command{awk}
 commands in a program.  This can be very enlightening, as the following
 partial dump of Davide Brini's obfuscated code
 (@pxref{Signature Program}) demonstrates:
@@ -29038,51 +29126,51 @@ partial dump of Davide Brini's obfuscated code
 @smallexample
 gawk> @kbd{dump}
 @print{}        # BEGIN
-@print{} 
-@print{} [     1:0xfcd340] Op_rule             : [in_rule = BEGIN] [source_file = brini.awk]
-@print{} [     1:0xfcc240] Op_push_i           : "~" [MALLOC|STRING|STRCUR]
-@print{} [     1:0xfcc2a0] Op_push_i           : "~" [MALLOC|STRING|STRCUR]
-@print{} [     1:0xfcc280] Op_match            : 
-@print{} [     1:0xfcc1e0] Op_store_var        : O
-@print{} [     1:0xfcc2e0] Op_push_i           : "==" [MALLOC|STRING|STRCUR]
-@print{} [     1:0xfcc340] Op_push_i           : "==" [MALLOC|STRING|STRCUR]
-@print{} [     1:0xfcc320] Op_equal            : 
-@print{} [     1:0xfcc200] Op_store_var        : o
-@print{} [     1:0xfcc380] Op_push             : o
-@print{} [     1:0xfcc360] Op_plus_i           : 0 [MALLOC|NUMCUR|NUMBER]
-@print{} [     1:0xfcc220] Op_push_lhs         : o [do_reference = true]
-@print{} [     1:0xfcc300] Op_assign_plus      : 
-@print{} [      :0xfcc2c0] Op_pop              : 
-@print{} [     1:0xfcc400] Op_push             : O
-@print{} [     1:0xfcc420] Op_push_i           : "" [MALLOC|STRING|STRCUR]
-@print{} [      :0xfcc4a0] Op_no_op            : 
-@print{} [     1:0xfcc480] Op_push             : O
-@print{} [      :0xfcc4c0] Op_concat           : [expr_count = 3] [concat_flag = 0]
-@print{} [     1:0xfcc3c0] Op_store_var        : x
-@print{} [     1:0xfcc440] Op_push_lhs         : X [do_reference = true]
-@print{} [     1:0xfcc3a0] Op_postincrement    : 
-@print{} [     1:0xfcc4e0] Op_push             : x
-@print{} [     1:0xfcc540] Op_push             : o
-@print{} [     1:0xfcc500] Op_plus             : 
-@print{} [     1:0xfcc580] Op_push             : o
-@print{} [     1:0xfcc560] Op_plus             : 
-@print{} [     1:0xfcc460] Op_leq              : 
-@print{} [      :0xfcc5c0] Op_jmp_false        : [target_jmp = 0xfcc5e0]
-@print{} [     1:0xfcc600] Op_push_i           : "%c" [MALLOC|STRING|STRCUR]
-@print{} [      :0xfcc660] Op_no_op            : 
-@print{} [     1:0xfcc520] Op_assign_concat    : c
-@print{} [      :0xfcc620] Op_jmp              : [target_jmp = 0xfcc440]
-@print{} 
-@dots{} 
-@print{} 
+@print{}
+@print{} [  1:0xfcd340] Op_rule           : [in_rule = BEGIN] [source_file = brini.awk]
+@print{} [  1:0xfcc240] Op_push_i         : "~" [MALLOC|STRING|STRCUR]
+@print{} [  1:0xfcc2a0] Op_push_i         : "~" [MALLOC|STRING|STRCUR]
+@print{} [  1:0xfcc280] Op_match          :
+@print{} [  1:0xfcc1e0] Op_store_var      : O
+@print{} [  1:0xfcc2e0] Op_push_i         : "==" [MALLOC|STRING|STRCUR]
+@print{} [  1:0xfcc340] Op_push_i         : "==" [MALLOC|STRING|STRCUR]
+@print{} [  1:0xfcc320] Op_equal          :
+@print{} [  1:0xfcc200] Op_store_var      : o
+@print{} [  1:0xfcc380] Op_push           : o
+@print{} [  1:0xfcc360] Op_plus_i         : 0 [MALLOC|NUMCUR|NUMBER]
+@print{} [  1:0xfcc220] Op_push_lhs       : o [do_reference = true]
+@print{} [  1:0xfcc300] Op_assign_plus    :
+@print{} [   :0xfcc2c0] Op_pop            :
+@print{} [  1:0xfcc400] Op_push           : O
+@print{} [  1:0xfcc420] Op_push_i         : "" [MALLOC|STRING|STRCUR]
+@print{} [   :0xfcc4a0] Op_no_op          :
+@print{} [  1:0xfcc480] Op_push           : O
+@print{} [   :0xfcc4c0] Op_concat         : [expr_count = 3] [concat_flag = 0]
+@print{} [  1:0xfcc3c0] Op_store_var      : x
+@print{} [  1:0xfcc440] Op_push_lhs       : X [do_reference = true]
+@print{} [  1:0xfcc3a0] Op_postincrement  :
+@print{} [  1:0xfcc4e0] Op_push           : x
+@print{} [  1:0xfcc540] Op_push           : o
+@print{} [  1:0xfcc500] Op_plus           :
+@print{} [  1:0xfcc580] Op_push           : o
+@print{} [  1:0xfcc560] Op_plus           :
+@print{} [  1:0xfcc460] Op_leq            :
+@print{} [   :0xfcc5c0] Op_jmp_false      : [target_jmp = 0xfcc5e0]
+@print{} [  1:0xfcc600] Op_push_i         : "%c" [MALLOC|STRING|STRCUR]
+@print{} [   :0xfcc660] Op_no_op          :
+@print{} [  1:0xfcc520] Op_assign_concat  : c
+@print{} [   :0xfcc620] Op_jmp            : [target_jmp = 0xfcc440]
+@print{}
+@dots{}
+@print{}
 @print{} [     2:0xfcc5a0] Op_K_printf         : [expr_count = 17] [redir_type = ""]
-@print{} [      :0xfcc140] Op_no_op            : 
-@print{} [      :0xfcc1c0] Op_atexit           : 
-@print{} [      :0xfcc640] Op_stop             : 
-@print{} [      :0xfcc180] Op_no_op            : 
-@print{} [      :0xfcd150] Op_after_beginfile  : 
-@print{} [      :0xfcc160] Op_no_op            : 
-@print{} [      :0xfcc1a0] Op_after_endfile    : 
+@print{} [      :0xfcc140] Op_no_op            :
+@print{} [      :0xfcc1c0] Op_atexit           :
+@print{} [      :0xfcc640] Op_stop             :
+@print{} [      :0xfcc180] Op_no_op            :
+@print{} [      :0xfcd150] Op_after_beginfile  :
+@print{} [      :0xfcc160] Op_no_op            :
+@print{} [      :0xfcc1a0] Op_after_endfile    :
 gawk>
 @end smallexample
 
@@ -29126,7 +29214,7 @@ Print lines centered around line number @var{n} in
 source file @var{filename}. This command may change the current source file.
 
 @item @var{function}
-Print lines centered around beginning of the
+Print lines centered around the beginning of the
 function @var{function}. This command may change the current source file.
 @end table
 
@@ -29138,16 +29226,16 @@ function @var{function}. This command may change the current source file.
 @item @code{quit}
 @itemx @code{q}
 Exit the debugger.  Debugging is great fun, but sometimes we all have
-to tend to other obligations in life, and sometimes we find the bug,
-and are free to go on to the next one!  As we saw above, if you are
-running a program, the debugger warns you if you accidentally type
+to tend to other obligations in life, and sometimes we find the bug
+and are free to go on to the next one!  As we saw earlier, if you are
+running a program, the debugger warns you when you type
 @samp{q} or @samp{quit}, to make sure you really want to quit.
 
 @cindex debugger commands, @code{trace}
 @cindex @code{trace} debugger command
 @item @code{trace} [@code{on} | @code{off}]
-Turn on or off a continuous printing of instructions which are about to
-be executed, along with printing the @command{awk} line which they
+Turn on or off continuous printing of the instructions that are about to
+be executed, along with the @command{awk} lines they
 implement.  The default is @code{off}.
 
 It is to be hoped that most of the ``opcodes'' in these instructions are
@@ -29163,7 +29251,7 @@ fairly self-explanatory, and using @code{stepi} and @code{nexti} while
 
 If @command{gawk} is compiled with
 @uref{http://cnswww.cns.cwru.edu/php/chet/readline/readline.html,
-the @code{readline} library}, you can take advantage of that library's
+the GNU Readline library}, you can take advantage of that library's
 command completion and history expansion features. The following types
 of completion are available:
 
@@ -29200,7 +29288,7 @@ and
 
 We hope you find the @command{gawk} debugger useful and enjoyable to work with,
 but as with any program, especially in its early releases, it still has
-some limitations.  A few which are worth being aware of are:
+some limitations.  A few that it's worth being aware of are:
 
 @itemize @value{BULLET}
 @item
@@ -29216,13 +29304,13 @@ If you perused the dump of opcodes in @ref{Miscellaneous Debugger Commands}
 (or if you are already familiar with @command{gawk} internals),
 you will realize that much of the internal manipulation of data
 in @command{gawk}, as in many interpreters, is done on a stack.
-@code{Op_push}, @code{Op_pop}, etc., are the ``bread and butter'' of
+@code{Op_push}, @code{Op_pop}, and the like are the ``bread and butter'' of
 most @command{gawk} code.
 
 Unfortunately, as of now, the @command{gawk}
 debugger does not allow you to examine the stack's contents.
 That is, the intermediate results of expression evaluation are on the
-stack, but cannot be printed.  Rather, only variables which are defined
+stack, but cannot be printed.  Rather, only variables that are defined
 in the program can be printed.  Of course, a workaround for
 this is to use more explicit variables at the debugging stage and then
 change back to obscure, perhaps more optimal code later.
@@ -29230,18 +29318,18 @@ change back to obscure, perhaps more optimal code later.
 @item
 There is no way to look ``inside'' the process of compiling
 regular expressions to see if you got it right.  As an @command{awk}
-programmer, you are expected to know what @code{/[^[:alnum:][:blank:]]/}
-means.
+programmer, you are expected to know the meaning of
+@code{/[^[:alnum:][:blank:]]/}.
 
 @item
 The @command{gawk} debugger is designed to be used by running a program (with all its
 parameters) on the command line, as described in @ref{Debugger Invocation}.
-There is no way (as of now) to attach or ``break in'' to a running program.
-This seems reasonable for a language which is used mainly for quickly
+There is no way (as of now) to attach or ``break into'' a running program.
+This seems reasonable for a language that is used mainly for quickly
 executing, short programs.
 
 @item
-The @command{gawk} debugger only accepts source supplied with the @option{-f} option.
+The @command{gawk} debugger only accepts source code supplied with the @option{-f} option.
 @end itemize
 
 @ignore
@@ -29255,8 +29343,8 @@ be added, and of course feel free to try to add them yourself!
 @itemize @value{BULLET}
 @item
 Programs rarely work correctly the first time.  Finding bugs
-is @dfn{debugging} and a program that helps you find bugs is a
-@dfn{debugger}.  @command{gawk} has a built-in debugger that works very
+is called debugging, and a program that helps you find bugs is a
+debugger.  @command{gawk} has a built-in debugger that works very
 similarly to the GNU Debugger, GDB.
 
 @item
@@ -29276,14 +29364,14 @@ breakpoints, execution, viewing and changing data, working with the stack,
 getting information, and other tasks.
 
 @item
-If the @code{readline} library is available when @command{gawk} is
+If the GNU Readline library is available when @command{gawk} is
 compiled, it is used by the debugger to provide command-line history
 and editing.
 
 @end itemize
 
 @node Arbitrary Precision Arithmetic
-@chapter Arithmetic and Arbitrary Precision Arithmetic with @command{gawk}
+@chapter Arithmetic and Arbitrary-Precision Arithmetic with @command{gawk}
 @cindex arbitrary precision
 @cindex multiple precision
 @cindex infinite precision
@@ -29293,9 +29381,9 @@ This @value{CHAPTER} introduces some basic concepts relating to
 how computers do arithmetic and defines some important terms.
 It then proceeds to describe floating-point arithmetic,
 which is what @command{awk} uses for all its computations, including a
-discussion of arbitrary precision floating point arithmetic, which is
+discussion of arbitrary-precision floating-point arithmetic, which is
 a feature available only in @command{gawk}. It continues on to present
-arbitrary precision integers, and concludes with a description of some
+arbitrary-precision integers, and concludes with a description of some
 points where @command{gawk} and the POSIX standard are not quite in
 agreement.
 
@@ -29340,7 +29428,7 @@ paper and pencil (and/or a calculator). In theory, numbers can have an
 arbitrary number of digits on either side (or both sides) of the decimal
 point, and the results of a computation are always exact.
 
-Some modern system can do decimal arithmetic in hardware, but usually you
+Some modern systems can do decimal arithmetic in hardware, but usually you
 need a special software library to provide access to these instructions.
 There are also libraries that do decimal arithmetic entirely in software.
 
@@ -29358,55 +29446,82 @@ The disadvantage is that their range is limited.
 @cindex integers, unsigned
 In computers, integer values come in two flavors: @dfn{signed} and
 @dfn{unsigned}.  Signed values may be negative or positive, whereas
-unsigned values are always positive (that is, greater than or equal
-to zero).
+unsigned values are always greater than or equal
+to zero.
 
 In computer systems, integer arithmetic is exact, but the possible
 range of values is limited.  Integer arithmetic is generally faster than
-floating point arithmetic.
+floating-point arithmetic.
 
-@item Floating point arithmetic
+@item Floating-point arithmetic
 Floating-point numbers represent what were called in school ``real''
-numbers; i.e., those that have a fractional part, such as 3.1415927.
+numbers (i.e., those that have a fractional part, such as 3.1415927).
 The advantage to floating-point numbers is that they can represent a
 much larger range of values than can integers.  The disadvantage is that
 there are numbers that they cannot represent exactly.
 
-Modern systems support floating point arithmetic in hardware, with a
+Modern systems support floating-point arithmetic in hardware, with a
 limited range of values.  There are software libraries that allow
-the use of arbitrary precision floating point calculations.
+the use of arbitrary-precision floating-point calculations.
 
-POSIX @command{awk} uses @dfn{double precision} floating-point numbers, which
-can hold more digits than @dfn{single precision} floating-point numbers.
-@command{gawk} has facilities for performing arbitrary precision floating
-point arithmetic, which we describe in more detail shortly.
+POSIX @command{awk} uses @dfn{double-precision} floating-point numbers, which
+can hold more digits than @dfn{single-precision} floating-point numbers.
+@command{gawk} has facilities for performing arbitrary-precision
+floating-point arithmetic, which we describe in more detail shortly.
 @end table
 
-Computers work with integer and floating point values of different
-ranges. Integer values are usually either 32 or 64 bits in size.  Single
-precision floating point values occupy 32 bits, whereas double precision
-floating point values occupy 64 bits.  Floating point values are always
+Computers work with integer and floating-point values of different
+ranges. Integer values are usually either 32 or 64 bits in size.
+Single-precision floating-point values occupy 32 bits, whereas double-precision
+floating-point values occupy 64 bits.  Floating-point values are always
 signed. The possible ranges of values are shown in @ref{table-numeric-ranges}.
 
 @float Table,table-numeric-ranges
-@caption{Value Ranges for Different Numeric Representations}
+@caption{Value ranges for different numeric representations}
 @multitable @columnfractions .34 .33 .33
 @headitem Numeric representation @tab Minimum value @tab Maximum value
 @item 32-bit signed integer @tab @minus{}2,147,483,648 @tab 2,147,483,647
 @item 32-bit unsigned integer @tab 0 @tab 4,294,967,295
 @item 64-bit signed integer @tab @minus{}9,223,372,036,854,775,808 @tab 9,223,372,036,854,775,807
 @item 64-bit unsigned integer @tab 0 @tab 18,446,744,073,709,551,615
-@item Single precision floating point (approximate) @tab @code{1.175494e-38} @tab @code{3.402823e+38}
-@item Double precision floating point (approximate) @tab @code{2.225074e-308} @tab @code{1.797693e+308}
+@iftex
+@item Single-precision floating point (approximate) @tab @math{1.175494^{-38}} @tab @math{3.402823^{38}}
+@item Double-precision floating point (approximate) @tab @math{2.225074^{-308}} @tab @math{1.797693^{308}}
+@end iftex
+@ifnottex
+@ifnotdocbook
+@item Single-precision floating point (approximate) @tab 1.175494e-38 @tab 3.402823e38
+@item Double-precision floating point (approximate) @tab 2.225074e-308 @tab 1.797693e308
+@end ifnotdocbook
+@end ifnottex
+@ifdocbook
+@item Single-precision floating point (approximate) @tab
+@c FIXME: Use @sup here for superscript
+@docbook
+1.175494<superscript>-38</superscript>
+@end docbook
+@tab
+@docbook
+3.402823<superscript>38</superscript>
+@end docbook
+@item Double-precision floating point (approximate) @tab
+@docbook
+2.225074<superscript>-308</superscript>
+@end docbook
+@tab
+@docbook
+1.797693<superscript>308</superscript>
+@end docbook
+@end ifdocbook
 @end multitable
 @end float
 
 @node Math Definitions
-@section Other Stuff To Know
+@section Other Stuff to Know
 
 The rest of this @value{CHAPTER} uses a number of terms. Here are some
 informal definitions that should help you work your way through the material
-here.
+here:
 
 @table @dfn
 @item Accuracy
@@ -29427,7 +29542,7 @@ A special value representing infinity. Operations involving another
 number and infinity produce infinity.
 
 @item NaN
-``Not A Number.''@footnote{Thanks to Michael Brennan for this description,
+``Not a number.''@footnote{Thanks to Michael Brennan for this description,
 which we have paraphrased, and for the examples.} A special value that
 results from attempting a calculation that has no answer as a real number.
 In such a case, programs can either receive a floating-point exception,
@@ -29470,8 +29585,8 @@ formula:
 @end display
 
 @noindent
-Here, @var{prec} denotes the binary precision
-(measured in bits) and @var{dps} (short for decimal places)
+Here, @emph{prec} denotes the binary precision
+(measured in bits) and @emph{dps} (short for decimal places)
 is the decimal digits.
 
 @item Rounding mode
@@ -29479,7 +29594,7 @@ How numbers are rounded up or down when necessary.
 More details are provided later.
 
 @item Significand
-A floating point value consists the significand multiplied by 10
+A floating-point value consists of the significand multiplied by 10
 to the power of the exponent. For example, in @code{1.2345e67},
 the significand is @code{1.2345}.
 
@@ -29497,19 +29612,19 @@ on some of those terms.
 On modern systems, floating-point hardware uses the representation and
 operations defined by the IEEE 754 standard.
 Three of the standard IEEE 754 types are 32-bit single precision,
-64-bit double precision and 128-bit quadruple precision.
+64-bit double precision, and 128-bit quadruple precision.
 The standard also specifies extended precision formats
 to allow greater precisions and larger exponent ranges.
-(@command{awk} uses only the 64-bit double precision format.)
+(@command{awk} uses only the 64-bit double-precision format.)
 
 @ref{table-ieee-formats} lists the precision and exponent
-field values for the basic IEEE 754 binary formats:
+field values for the basic IEEE 754 binary formats.
 
 @float Table,table-ieee-formats
-@caption{Basic IEEE Format Values}
+@caption{Basic IEEE format values}
 @multitable @columnfractions .20 .20 .20 .20 .20
 @headitem Name @tab Total bits @tab Precision @tab Minimum exponent @tab Maximum exponent
-@item Single @tab 32 @tab 24 @tab @minus{}126 @tab +127 
+@item Single @tab 32 @tab 24 @tab @minus{}126 @tab +127
 @item Double @tab 64 @tab 53 @tab @minus{}1022 @tab +1023
 @item Quadruple @tab 128 @tab 113 @tab @minus{}16382 @tab +16383
 @end multitable
@@ -29521,19 +29636,19 @@ one extra bit of significand.
 @end quotation
 
 @node MPFR features
-@section Arbitrary Precision Arithmetic Features In @command{gawk}
+@section Arbitrary-Precision Arithmetic Features in @command{gawk}
 
-By default, @command{gawk} uses the double precision floating-point values
+By default, @command{gawk} uses the double-precision floating-point values
 supplied by the hardware of the system it runs on.  However, if it was
-compiled to do so, @command{gawk} uses the @uref{http://www.mpfr.org
-GNU MPFR} and @uref{http://gmplib.org, GNU MP} (GMP) libraries for arbitrary
-precision arithmetic on numbers.  You can see if MPFR support is available
-like so:
+compiled to do so, @command{gawk} uses the @uref{http://www.mpfr.org,
+GNU MPFR} and @uref{http://gmplib.org, GNU MP} (GMP) libraries for
+arbitrary-precision arithmetic on numbers.  You can see if MPFR support
+is available like so:
 
 @example
 $ @kbd{gawk --version}
 @print{} GNU Awk 4.1.2, API: 1.1 (GNU MPFR 3.1.0-p3, GNU MP 5.0.2)
-@print{} Copyright (C) 1989, 1991-2014 Free Software Foundation.
+@print{} Copyright (C) 1989, 1991-2015 Free Software Foundation.
 @dots{}
 @end example
 
@@ -29556,23 +29671,23 @@ Two predefined variables, @code{PREC} and @code{ROUNDMODE},
 provide control over the working precision and the rounding mode.
 The precision and the rounding mode are set globally for every operation
 to follow.
-@xref{Setting precision}, and @ref{Setting the rounding mode},
+@DBXREF{Setting precision} and @DBREF{Setting the rounding mode}
 for more information.
 
 @node FP Math Caution
-@section Floating Point Arithmetic: Caveat Emptor!
+@section Floating-Point Arithmetic: Caveat Emptor!
 
 @quotation
 @i{Math class is tough!}
 @author Teen Talk Barbie, July 1992
 @end quotation
 
-This @value{SECTION} provides a high level overview of the issues
+This @value{SECTION} provides a high-level overview of the issues
 involved when doing lots of floating-point arithmetic.@footnote{There
 is a very nice @uref{http://www.validlab.com/goldberg/paper.pdf,
 paper on floating-point arithmetic} by David Goldberg, ``What Every
-Computer Scientist Should Know About Floating-point Arithmetic,''
-@cite{ACM Computing Surveys} @strong{23}, 1 (1991-03), 5-48.  This is
+Computer Scientist Should Know About Floating-Point Arithmetic,''
+@cite{ACM Computing Surveys} @strong{23}, 1 (1991-03): 5-48.  This is
 worth reading if you are interested in the details, but it does require
 a background in computer science.}
 The discussion applies to both hardware and arbitrary-precision
@@ -29593,17 +29708,17 @@ rely just on what we tell you.
 @end menu
 
 @node Inexactness of computations
-@subsection Floating Point Arithmetic Is Not Exact
+@subsection Floating-Point Arithmetic Is Not Exact
 
 Binary floating-point representations and arithmetic are inexact.
 Simple values like 0.1 cannot be precisely represented using
 binary floating-point numbers, and the limited precision of
 floating-point numbers means that slight changes in
 the order of operations or the precision of intermediate storage
-can change the result. To make matters worse, with arbitrary precision
-floating-point, you can set the precision before starting a computation,
-but then you cannot be sure of the number of significant decimal places
-in the final result.
+can change the result. To make matters worse, with arbitrary-precision
+floating-point arithmetic, you can set the precision before starting a
+computation, but then you cannot be sure of the number of significant
+decimal places in the final result.
 
 @menu
 * Inexact representation::      Numbers are not exactly represented.
@@ -29625,7 +29740,7 @@ y = 0.425
 
 Unlike the number in @code{y}, the number stored in @code{x}
 is exactly representable
-in binary since it can be written as a finite sum of one or
+in binary because it can be written as a finite sum of one or
 more fractions whose denominators are all powers of two.
 When @command{gawk} reads a floating-point number from
 program source, it automatically rounds that number to whatever
@@ -29641,7 +29756,7 @@ $ @kbd{gawk 'BEGIN @{ x = 0.875; y = 0.425}
 
 Often the error is so small you do not even notice it, and if you do,
 you can always specify how much precision you would like in your output.
-Usually this is a format string like @code{"%.15g"}, which when
+Usually this is a format string like @code{"%.15g"}, which, when
 used in the previous example, produces an output identical to the input.
 
 @node Comparing FP Values
@@ -29651,7 +29766,7 @@ Because the underlying representation can be a little bit off from the exact val
 comparing floating-point values to see if they are exactly equal is generally a bad idea.
 Here is an example where it does not work like you would expect:
 
-@example 
+@example
 $ @kbd{gawk 'BEGIN @{ print (0.1 + 12.2 == 12.3) @}'}
 @print{} 0
 @end example
@@ -29660,7 +29775,7 @@ The general wisdom when comparing floating-point values is to see if
 they are within some small range of each other (called a @dfn{delta},
 or @dfn{tolerance}).
 You have to decide how small a delta is important to you. Code to do
-this looks something like this:
+this looks something like the following:
 
 @example
 delta = 0.00001                 # for example
@@ -29680,7 +29795,7 @@ else
 
 The loss of accuracy during a single computation with floating-point
 numbers usually isn't enough to worry about. However, if you compute a
-value which is the result of a sequence of floating point operations,
+value that is the result of a sequence of floating-point operations,
 the error can accumulate and greatly affect the computation itself.
 Here is an attempt to compute the value of @value{PI} using one of its
 many series representations:
@@ -29726,23 +29841,23 @@ $ @kbd{gawk 'BEGIN @{}
 @end example
 
 @node Getting Accuracy
-@subsection Getting The Accuracy You Need
+@subsection Getting the Accuracy You Need
 
-Can arbitrary precision arithmetic give exact results? There are
+Can arbitrary-precision arithmetic give exact results? There are
 no easy answers. The standard rules of algebra often do not apply
 when using floating-point arithmetic.
 Among other things, the distributive and associative laws
 do not hold completely, and order of operation may be important
-for your computation. Rounding error, cumulative precision loss
+for your computation. Rounding error, cumulative precision loss,
 and underflow are often troublesome.
 
 When @command{gawk} tests the expressions @samp{0.1 + 12.2} and
-@samp{12.3} for equality using the machine double precision arithmetic,
+@samp{12.3} for equality using the machine double-precision arithmetic,
 it decides that they are not equal!  (@xref{Comparing FP Values}.)
 You can get the result you want by increasing the precision; 56 bits in
 this case does the job:
 
-@example 
+@example
 $ @kbd{gawk -M -v PREC=56 'BEGIN @{ print (0.1 + 12.2 == 12.3) @}'}
 @print{} 1
 @end example
@@ -29751,7 +29866,7 @@ If adding more bits is good, perhaps adding even more bits of
 precision is better?
 Here is what happens if we use an even larger value of @code{PREC}:
 
-@example 
+@example
 $ @kbd{gawk -M -v PREC=201 'BEGIN @{ print (0.1 + 12.2 == 12.3) @}'}
 @print{} 0
 @end example
@@ -29760,20 +29875,21 @@ This is not a bug in @command{gawk} or in the MPFR library.
 It is easy to forget that the finite number of bits used to store the value
 is often just an approximation after proper rounding.
 The test for equality succeeds if and only if @emph{all} bits in the two operands
-are exactly the same. Since this is not necessarily true after floating-point
+are exactly the same. Because this is not necessarily true after floating-point
 computations with a particular precision and effective rounding mode,
 a straight test for equality may not work. Instead, compare the
 two numbers to see if they are within the desirable delta of each other.
 
 In applications where 15 or fewer decimal places suffice,
-hardware double precision arithmetic can be adequate, and is usually much faster.
+hardware double-precision arithmetic can be adequate, and is usually much faster.
 But you need to keep in mind that every floating-point operation
-can suffer a new rounding error with catastrophic consequences as illustrated
+can suffer a new rounding error with catastrophic consequences, as illustrated
 by our earlier attempt to compute the value of @value{PI}.
 Extra precision can greatly enhance the stability and the accuracy
 of your computation in such cases.
 
-Repeated addition is not necessarily equivalent to multiplication
+Additionally, you should understand that
+repeated addition is not necessarily equivalent to multiplication
 in floating-point arithmetic. In the example in
 @ref{Errors accumulate}:
 
@@ -29792,9 +29908,9 @@ an arbitrarily large value for @code{PREC}. Reformulation of
 the problem at hand is often the correct approach in such situations.
 
 @node Try To Round
-@subsection Try A Few Extra Bits of Precision and Rounding
+@subsection Try a Few Extra Bits of Precision and Rounding
 
-Instead of arbitrary precision floating-point arithmetic,
+Instead of arbitrary-precision floating-point arithmetic,
 often all you need is an adjustment of your logic
 or a different order for the operations in your calculation.
 The stability and the accuracy of the computation of @value{PI}
@@ -29806,7 +29922,7 @@ simple algebraic transformation:
 @end example
 
 @noindent
-After making this, change the program converges to
+After making this change, the program converges to
 @value{PI} in under 30 iterations:
 
 @example
@@ -29822,7 +29938,7 @@ $ @kbd{gawk -f pi2.awk}
 @end example
 
 @node Setting precision
-@subsection Setting The Precision
+@subsection Setting the Precision
 
 @command{gawk} uses a global working precision; it does not keep track of
 the precision or accuracy of individual numbers. Performing an arithmetic
@@ -29834,14 +29950,14 @@ shown in @ref{table-predefined-precision-strings},
 to emulate an IEEE 754 binary format.
 
 @float Table,table-predefined-precision-strings
-@caption{Predefined Precision Strings For @code{PREC}}
+@caption{Predefined precision strings for @code{PREC}}
 @multitable {@code{"double"}} {12345678901234567890123456789012345}
-@headitem @code{PREC} @tab IEEE 754 Binary Format
-@item @code{"half"} @tab 16-bit half-precision.
-@item @code{"single"} @tab Basic 32-bit single precision.
-@item @code{"double"} @tab Basic 64-bit double precision.
-@item @code{"quad"} @tab Basic 128-bit quadruple precision.
-@item @code{"oct"} @tab 256-bit octuple precision.
+@headitem @code{PREC} @tab IEEE 754 binary format
+@item @code{"half"} @tab 16-bit half-precision
+@item @code{"single"} @tab Basic 32-bit single precision
+@item @code{"double"} @tab Basic 64-bit double precision
+@item @code{"quad"} @tab Basic 128-bit quadruple precision
+@item @code{"oct"} @tab 256-bit octuple precision
 @end multitable
 @end float
 
@@ -29868,11 +29984,10 @@ than the default and cannot use a command-line assignment to @code{PREC},
 you should either specify the constant as a string, or as a rational
 number, whenever possible. The following example illustrates the
 differences among various ways to print a floating-point constant:
-@end quotation
 
 @example
 $ @kbd{gawk -M 'BEGIN @{ PREC = 113; printf("%0.25f\n", 0.1) @}'}
-@print{} 0.1000000000000000055511151 
+@print{} 0.1000000000000000055511151
 $ @kbd{gawk -M -v PREC=113 'BEGIN @{ printf("%0.25f\n", 0.1) @}'}
 @print{} 0.1000000000000000000000000
 $ @kbd{gawk -M 'BEGIN @{ PREC = 113; printf("%0.25f\n", "0.1") @}'}
@@ -29880,22 +29995,23 @@ $ @kbd{gawk -M 'BEGIN @{ PREC = 113; printf("%0.25f\n", "0.1") @}'}
 $ @kbd{gawk -M 'BEGIN @{ PREC = 113; printf("%0.25f\n", 1/10) @}'}
 @print{} 0.1000000000000000000000000
 @end example
+@end quotation
 
 @node Setting the rounding mode
-@subsection Setting The Rounding Mode
+@subsection Setting the Rounding Mode
 
 The @code{ROUNDMODE} variable provides
-program level control over the rounding mode.
+program-level control over the rounding mode.
 The correspondence between @code{ROUNDMODE} and the IEEE
 rounding modes is shown in @ref{table-gawk-rounding-modes}.
 
 @float Table,table-gawk-rounding-modes
-@caption{@command{gawk} Rounding Modes}
+@caption{@command{gawk} rounding modes}
 @multitable @columnfractions .45 .30 .25
-@headitem Rounding Mode @tab IEEE Name @tab @code{ROUNDMODE}
+@headitem Rounding mode @tab IEEE name @tab @code{ROUNDMODE}
 @item Round to nearest, ties to even @tab @code{roundTiesToEven} @tab @code{"N"} or @code{"n"}
-@item Round toward plus Infinity @tab @code{roundTowardPositive} @tab @code{"U"} or @code{"u"}
-@item Round toward negative Infinity @tab @code{roundTowardNegative} @tab @code{"D"} or @code{"d"}
+@item Round toward positive infinity @tab @code{roundTowardPositive} @tab @code{"U"} or @code{"u"}
+@item Round toward negative infinity @tab @code{roundTowardNegative} @tab @code{"D"} or @code{"d"}
 @item Round toward zero @tab @code{roundTowardZero} @tab @code{"Z"} or @code{"z"}
 @item Round to nearest, ties away from zero @tab @code{roundTiesToAway} @tab @code{"A"} or @code{"a"}
 @end multitable
@@ -29905,7 +30021,7 @@ rounding modes is shown in @ref{table-gawk-rounding-modes}.
 selects the IEEE 754 rounding mode @code{roundTiesToEven}.
 In @ref{table-gawk-rounding-modes}, the value @code{"A"} selects
 @code{roundTiesToAway}.  This is only available if your version of the
-MPFR library supports it; otherwise setting @code{ROUNDMODE} to @code{"A"}
+MPFR library supports it; otherwise, setting @code{ROUNDMODE} to @code{"A"}
 has no effect.
 
 The default mode @code{roundTiesToEven} is the most preferred,
@@ -29956,8 +30072,8 @@ distributes upward and downward rounds of exact halves, which might
 cause any accumulating round-off error to cancel itself out. This is the
 default rounding mode for IEEE 754 computing functions and operators.
 
-The other rounding modes are rarely used.  Round toward positive infinity
-(@code{roundTowardPositive}) and round toward negative infinity
+The other rounding modes are rarely used.  Rounding toward positive infinity
+(@code{roundTowardPositive}) and toward negative infinity
 (@code{roundTowardNegative}) are often used to implement interval
 arithmetic, where you adjust the rounding mode to calculate upper and
 lower bounds for the range of output. The @code{roundTowardZero} mode can
@@ -29976,14 +30092,14 @@ accumulation of round-off error, look for a significant difference in
 output when you change the rounding mode to be sure.
 
 @node Arbitrary Precision Integers
-@section Arbitrary Precision Integer Arithmetic with @command{gawk}
+@section Arbitrary-Precision Integer Arithmetic with @command{gawk}
 @cindex integers, arbitrary precision
 @cindex arbitrary precision integers
 
 When given the @option{-M} option,
-@command{gawk} performs all integer arithmetic using GMP arbitrary
-precision integers.  Any number that looks like an integer in a source
-or @value{DF} is stored as an arbitrary precision integer.  The size
+@command{gawk} performs all integer arithmetic using GMP arbitrary-precision
+integers.  Any number that looks like an integer in a source
+or @value{DF} is stored as an arbitrary-precision integer.  The size
 of the integer is limited only by the available memory.  For example,
 the following computes
 @iftex
@@ -29998,7 +30114,8 @@ the following computes
 5<superscript>4<superscript>3<superscript>2</superscript></superscript></superscript>, @c
 @end docbook
 the result of which is beyond the
-limits of ordinary hardware double precision floating point values:
+limits of ordinary hardware double-precision floating-point values:
+@c FIXME: Use @sup here for superscript
 
 @example
 $ @kbd{gawk -M 'BEGIN @{}
@@ -30010,21 +30127,21 @@ $ @kbd{gawk -M 'BEGIN @{}
 @print{} 62060698786608744707 ... 92256259918212890625
 @end example
 
-If instead you were to compute the same value using arbitrary precision
+If instead you were to compute the same value using arbitrary-precision
 floating-point values, the precision needed for correct output (using
 the formula
 @iftex
-@math{prec = 3.322 @cdot dps}),
+@math{prec = 3.322 @cdot dps})
 would be @math{3.322 @cdot 183231},
 @end iftex
 @ifnottex
 @ifnotdocbook
-@samp{prec = 3.322 * dps}),
+@samp{prec = 3.322 * dps})
 would be 3.322 x 183231,
 @end ifnotdocbook
 @end ifnottex
 @docbook
-<emphasis>prec</emphasis> = 3.322 &sdot; <emphasis>dps</emphasis>),
+<emphasis>prec</emphasis> = 3.322 &sdot; <emphasis>dps</emphasis>)
 would be
 <emphasis>prec</emphasis> = 3.322 &sdot; 183231, @c
 @end docbook
@@ -30055,14 +30172,14 @@ floating-point results exactly. You can either increase the precision
 @samp{2.0} with an integer, to perform all computations using integer
 arithmetic to get the correct output.
 
-Sometimes @command{gawk} must implicitly convert an arbitrary precision
-integer into an arbitrary precision floating-point value.  This is
+Sometimes @command{gawk} must implicitly convert an arbitrary-precision
+integer into an arbitrary-precision floating-point value.  This is
 primarily because the MPFR library does not always provide the relevant
-interface to process arbitrary precision integers or mixed-mode numbers
+interface to process arbitrary-precision integers or mixed-mode numbers
 as needed by an operation or function.  In such a case, the precision is
 set to the minimum value necessary for exact conversion, and the working
 precision is not used for this purpose.  If this is not what you need or
-want, you can employ a subterfuge, and convert the integer to floating
+want, you can employ a subterfuge and convert the integer to floating
 point first, like this:
 
 @example
@@ -30076,7 +30193,7 @@ to begin with:
 gawk -M 'BEGIN @{ n = 13.0; print n % 2.0 @}'
 @end example
 
-Note that for the particular example above, it is likely best
+Note that for this particular example, it is likely best
 to just use the following:
 
 @example
@@ -30088,27 +30205,30 @@ When dividing two arbitrary precision integers with either
 precision floating point value (unless the denominator evenly
 divides into the numerator).  In order to do integer division
 or remainder with arbitrary precision integers, use the built-in
-@code{div()} function (@pxref{Numeric Functions}).
+@code{intdiv()} function (@pxref{Numeric Functions}).
 
-You can simulate the @code{div()} function in standard @command{awk}
+You can simulate the @code{intdiv()} function in standard @command{awk}
 using this user-defined function:
 
 @example
-@c file eg/lib/div.awk
-# div --- do integer division
+@c file eg/lib/intdiv.awk
+# intdiv --- do integer division
 
 @c endfile
 @ignore
-@c file eg/lib/div.awk
+@c file eg/lib/intdiv.awk
 #
 # Arnold Robbins, arnold@@skeeve.com, Public Domain
 # July, 2014
+#
+# Name changed from div() to intdiv()
+# April, 2015
 
 @c endfile
 
 @end ignore
-@c file eg/lib/div.awk
-function div(numerator, denominator, result)
+@c file eg/lib/intdiv.awk
+function intdiv(numerator, denominator, result)
 @{
     split("", result)
 
@@ -30123,7 +30243,7 @@ function div(numerator, denominator, result)
 @end example
 
 The following example program, contributed by Katie Wasserman,
-uses @code{div()} to
+uses @code{intdiv()} to
 compute the digits of @value{PI} to as many places as you
 choose to set:
 
@@ -30148,7 +30268,7 @@ BEGIN @{
     for (m = digits * 4; m > 0; --m) @{
         d = m * 2 + 1
         x = pi * m
-        div(x, d, result)
+        intdiv(x, d, result)
         pi = result["quotient"]
         pi = pi + two
     @}
@@ -30187,7 +30307,7 @@ When asked about the algorithm used, Katie replied:
 @quotation
 It's not that well known but it's not that obscure either.
 It's Euler's modification to Newton's method for calculating pi.
-Take a look at lines (23) - (25) here: @uref{http://mathworld.wolfram.com/PiFormulas.htm}.
+Take a look at lines (23) - (25) here: @uref{http://mathworld.wolfram.com/PiFormulas.html}.
 
 The algorithm I wrote simply expands the multiply by 2 and works from
 the innermost expression outwards.  I used this to program HP calculators
@@ -30199,7 +30319,7 @@ word sizes. See
 @node POSIX Floating Point Problems
 @section Standards Versus Existing Practice
 
-Historically, @command{awk} has converted any non-numeric looking string
+Historically, @command{awk} has converted any nonnumeric-looking string
 to the numeric value zero, when required.  Furthermore, the original
 definition of the language and the original POSIX standards specified that
 @command{awk} only understands decimal numbers (base 10), and not octal
@@ -30211,13 +30331,13 @@ should support additional features.  These features are:
 
 @itemize @value{BULLET}
 @item
-Interpretation of floating point data values specified in hexadecimal
+Interpretation of floating-point data values specified in hexadecimal
 notation (e.g., @code{0xDEADBEEF}). (Note: data values, @emph{not}
 source code constants.)
 
 @item
-Support for the special IEEE 754 floating point values ``Not A Number''
-(NaN), positive Infinity (``inf'') and negative Infinity (``@minus{}inf'').
+Support for the special IEEE 754 floating-point values ``not a number''
+(NaN), positive infinity (``inf''), and negative infinity (``@minus{}inf'').
 In particular, the format for these values is as specified by the ISO 1999
 C standard, which ignores case and can allow implementation-dependent additional
 characters after the @samp{nan} and allow either @samp{inf} or @samp{infinity}.
@@ -30228,8 +30348,8 @@ practice:
 
 @itemize @value{BULLET}
 @item
-The @command{gawk} maintainer feels that supporting hexadecimal floating
-point values, in particular, is ugly, and was never intended by the
+The @command{gawk} maintainer feels that supporting hexadecimal
+floating-point values, in particular, is ugly, and was never intended by the
 original designers to be part of the language.
 
 @item
@@ -30237,22 +30357,22 @@ Allowing completely alphabetic strings to have valid numeric
 values is also a very severe departure from historical practice.
 @end itemize
 
-The second problem is that the @code{gawk} maintainer feels that this
-interpretation of the standard, which requires a certain amount of
+The second problem is that the @command{gawk} maintainer feels that this
+interpretation of the standard, which required a certain amount of
 ``language lawyering'' to arrive at in the first place, was not even
-intended by the standard developers.  In other words, ``we see how you
+intended by the standard developers.  In other words, ``We see how you
 got where you are, but we don't think that that's where you want to be.''
 
-Recognizing the above issues, but attempting to provide compatibility
+Recognizing these issues, but attempting to provide compatibility
 with the earlier versions of the standard,
 the 2008 POSIX standard added explicit wording to allow, but not require,
-that @command{awk} support hexadecimal floating point values and
-special values for ``Not A Number'' and infinity.
+that @command{awk} support hexadecimal floating-point values and
+special values for ``not a number'' and infinity.
 
 Although the @command{gawk} maintainer continues to feel that
 providing those features is inadvisable,
 nevertheless, on systems that support IEEE floating point, it seems
-reasonable to provide @emph{some} way to support NaN and Infinity values.
+reasonable to provide @emph{some} way to support NaN and infinity values.
 The solution implemented in @command{gawk} is as follows:
 
 @itemize @value{BULLET}
@@ -30272,7 +30392,7 @@ $ @kbd{echo 0xDeadBeef | gawk --posix '@{ print $1 + 0 @}'}
 @end example
 
 @item
-Without @option{--posix}, @command{gawk} interprets the four strings
+Without @option{--posix}, @command{gawk} interprets the four string values
 @samp{+inf},
 @samp{-inf},
 @samp{+nan},
@@ -30294,7 +30414,7 @@ $ @kbd{echo 0xDeadBeef | gawk '@{ print $1 + 0 @}'}
 @end example
 
 @command{gawk} ignores case in the four special values.
-Thus @samp{+nan} and @samp{+NaN} are the same.
+Thus, @samp{+nan} and @samp{+NaN} are the same.
 @end itemize
 
 @node Floating point summary
@@ -30303,13 +30423,13 @@ Thus @samp{+nan} and @samp{+NaN} are the same.
 @itemize @value{BULLET}
 @item
 Most computer arithmetic is done using either integers or floating-point
-values.  Standard @command{awk} uses double precision
+values.  Standard @command{awk} uses double-precision
 floating-point values.
 
 @item
-In the early 1990's, Barbie mistakenly said ``Math class is tough!''
-While math isn't tough, floating-point arithmetic isn't the same
-as pencil and paper math, and care must be taken:
+In the early 1990s Barbie mistakenly said, ``Math class is tough!''
+Although math isn't tough, floating-point arithmetic isn't the same
+as pencil-and-paper math, and care must be taken:
 
 @c nested list
 @itemize @value{MINUS}
@@ -30341,12 +30461,12 @@ arithmetic. Use @code{PREC} to set the precision in bits, and
 
 @item
 With @option{-M}, @command{gawk} performs
-arbitrary precision integer arithmetic using the GMP library.
-This is faster and more space efficient than using MPFR for
+arbitrary-precision integer arithmetic using the GMP library.
+This is faster and more space-efficient than using MPFR for
 the same calculations.
 
 @item
-There are several ``dark corners'' with respect to floating-point
+There are several areas with respect to floating-point
 numbers where @command{gawk} disagrees with the POSIX standard.
 It pays to be aware of them.
 
@@ -30354,7 +30474,7 @@ It pays to be aware of them.
 Overall, there is no need to be unduly suspicious about the results from
 floating-point arithmetic. The lesson to remember is that floating-point
 arithmetic is always more complex than arithmetic using pencil and
-paper. In order to take advantage of the power of computer floating-point,
+paper. In order to take advantage of the power of floating-point arithmetic,
 you need to know its limitations and work within them. For most casual
 use of floating-point arithmetic, you will often get the expected result
 if you simply round the display of your final results to the correct number
@@ -30396,7 +30516,7 @@ When @option{--sandbox} is specified, extensions are disabled
 * Finding Extensions::          How @command{gawk} finds compiled extensions.
 * Extension Example::           Example C code for an extension.
 * Extension Samples::           The sample extensions that ship with
-                                @code{gawk}.
+                                @command{gawk}.
 * gawkextlib::                  The @code{gawkextlib} project.
 * Extension summary::           Extension summary.
 * Extension Exercises::         Exercises.
@@ -30415,15 +30535,15 @@ Extensions are useful because they allow you (of course) to extend
 @command{gawk}'s functionality. For example, they can provide access to
 system calls (such as @code{chdir()} to change directory) and to other
 C library routines that could be of use.  As with most software,
-``the sky is the limit;'' if you can imagine something that you might
+``the sky is the limit''; if you can imagine something that you might
 want to do and can write in C or C++, you can write an extension to do it!
 
-Extensions are written in C or C++, using the @dfn{Application Programming
-Interface} (API) defined for this purpose by the @command{gawk}
+Extensions are written in C or C++, using the @dfn{application programming
+interface} (API) defined for this purpose by the @command{gawk}
 developers.  The rest of this @value{CHAPTER} explains
 the facilities that the API provides and how to use
 them, and presents a small example extension.  In addition, it documents
-the sample extensions included in the @command{gawk} distribution,
+the sample extensions included in the @command{gawk} distribution
 and describes the @code{gawkextlib} project.
 @ifclear FOR_PRINT
 @xref{Extension Design}, for a discussion of the extension mechanism
@@ -30456,7 +30576,7 @@ int plugin_is_GPL_compatible;
 @end example
 
 @node Extension Mechanism Outline
-@section At A High Level How It Works
+@section How It Works at a High Level
 
 Communication between
 @command{gawk} and an extension is two-way.  First, when an extension
@@ -30471,22 +30591,22 @@ This is shown in @inlineraw{docbook, <xref linkend="figure-load-extension"/>}.
 
 @ifnotdocbook
 @float Figure,figure-load-extension
-@caption{Loading The Extension}
+@caption{Loading the extension}
 @c FIXME: One day, it should not be necessary to have two cases,
 @c but rather just the one without the "txt" final argument.
 @c This applies to the other figures as well.
 @ifinfo
-@center @image{api-figure1, , , Loading The Extension, txt}
+@center @image{api-figure1, , , Loading the extension, txt}
 @end ifinfo
 @ifnotinfo
-@center @image{api-figure1, , , Loading The Extension}
+@center @image{api-figure1, , , Loading the extension}
 @end ifnotinfo
 @end float
 @end ifnotdocbook
 
 @docbook
 <figure id="figure-load-extension" float="0">
-<title>Loading The Extension</title>
+<title>Loading the extension</title>
 <mediaobject>
 <imageobject role="web"><imagedata fileref="api-figure1.png" format="PNG"/></imageobject>
 </mediaobject>
@@ -30506,19 +30626,19 @@ This is shown in @inlineraw{docbook, <xref linkend="figure-register-new-function
 
 @ifnotdocbook
 @float Figure,figure-register-new-function
-@caption{Registering A New Function}
+@caption{Registering a new function}
 @ifinfo
-@center @image{api-figure2, , , Registering A New Function, txt}
+@center @image{api-figure2, , , Registering a new Function, txt}
 @end ifinfo
 @ifnotinfo
-@center @image{api-figure2, , , Registering A New Function}
+@center @image{api-figure2, , , Registering a new Function}
 @end ifnotinfo
 @end float
 @end ifnotdocbook
 
 @docbook
 <figure id="figure-register-new-function" float="0">
-<title>Registering A New Function</title>
+<title>Registering a new function</title>
 <mediaobject>
 <imageobject role="web"><imagedata fileref="api-figure2.png" format="PNG"/></imageobject>
 </mediaobject>
@@ -30539,7 +30659,7 @@ This is shown in @inlineraw{docbook, <xref linkend="figure-call-new-function"/>}
 
 @ifnotdocbook
 @float Figure,figure-call-new-function
-@caption{Calling The New Function}
+@caption{Calling the new function}
 @ifinfo
 @center @image{api-figure3, , , Calling the new function, txt}
 @end ifinfo
@@ -30551,7 +30671,7 @@ This is shown in @inlineraw{docbook, <xref linkend="figure-call-new-function"/>}
 
 @docbook
 <figure id="figure-call-new-function" float="0">
-<title>Calling The New Function</title>
+<title>Calling the new function</title>
 <mediaobject>
 <imageobject role="web"><imagedata fileref="api-figure3.png" format="PNG"/></imageobject>
 </mediaobject>
@@ -30576,7 +30696,7 @@ Some other bits and pieces:
 @itemize @value{BULLET}
 @item
 The API provides access to @command{gawk}'s @code{do_@var{xxx}} values,
-reflecting command-line options, like @code{do_lint}, @code{do_profiling}
+reflecting command-line options, like @code{do_lint}, @code{do_profiling},
 and so on (@pxref{Extension API Variables}).
 These are informational: an extension cannot affect their values
 inside @command{gawk}.  In addition, attempting to assign to them
@@ -30587,10 +30707,9 @@ The API also provides major and minor version numbers, so that an
 extension can check if the @command{gawk} it is loaded with supports the
 facilities it was compiled with.  (Version mismatches ``shouldn't''
 happen, but we all know how @emph{that} goes.)
-@xref{Extension Versioning}, for details.
+@DBXREF{Extension Versioning} for details.
 @end itemize
 
-
 @node Extension API Description
 @section API Description
 @cindex extension API
@@ -30614,6 +30733,7 @@ This (rather large) @value{SECTION} describes the API in detail.
 * Symbol Table Access::                  Functions for accessing global
                                          variables.
 * Array Manipulation::                   Functions for working with arrays.
+* Redirection API::                      How to access and manipulate redirections.
 * Extension API Variables::              Variables provided by the API.
 * Extension API Boilerplate::            Boilerplate code for using the API.
 @end menu
@@ -30621,7 +30741,7 @@ This (rather large) @value{SECTION} describes the API in detail.
 @node Extension API Functions Introduction
 @subsection Introduction
 
-Access to facilities within @command{gawk} are made available
+Access to facilities within @command{gawk} is achieved
 by calling through function pointers passed into your extension.
 
 API function pointers are provided for the following kinds of operations:
@@ -30632,21 +30752,24 @@ Allocating, reallocating, and releasing memory.
 
 @item
 Registration functions. You may register:
+
+@c nested list
 @itemize @value{MINUS}
 @item
-extension functions,
+Extension functions
 @item
-exit callbacks,
+Exit callbacks
 @item
-a version string,
+A version string
 @item
-input parsers,
+Input parsers
 @item
-output wrappers,
+Output wrappers
 @item
-and two-way processors.
+Two-way processors
 @end itemize
-All of these are discussed in detail, later in this @value{CHAPTER}.
+
+All of these are discussed in detail later in this @value{CHAPTER}.
 
 @item
 Printing fatal, warning, and ``lint'' warning messages.
@@ -30684,20 +30807,25 @@ Creating a new array
 Clearing an array
 
 @item
-Flattening an array for easy C style looping over all its indices and elements
+Flattening an array for easy C-style looping over all its indices and elements
 @end itemize
+
+@item
+Accessing and manipulating redirections.
+
 @end itemize
 
 Some points about using the API:
 
 @itemize @value{BULLET}
 @item
-The following types and/or macros and/or functions are referenced
+The following types, macros, and/or functions are referenced
 in @file{gawkapi.h}.  For correct use, you must therefore include the
 corresponding standard header file @emph{before} including @file{gawkapi.h}:
 
+@c FIXME: Make this is a float at some point.
 @multitable {@code{memset()}, @code{memcpy()}} {@code{<sys/types.h>}}
-@headitem C Entity @tab Header File
+@headitem C entity @tab Header file
 @item @code{EOF} @tab @code{<stdio.h>}
 @item Values for @code{errno} @tab @code{<errno.h>}
 @item @code{FILE} @tab @code{<stdio.h>}
@@ -30706,7 +30834,7 @@ corresponding standard header file @emph{before} including @file{gawkapi.h}:
 @item @code{memset()} @tab @code{<string.h>}
 @item @code{size_t} @tab @code{<sys/types.h>}
 @item @code{struct stat} @tab @code{<sys/stat.h>}
-@end multitable 
+@end multitable
 
 Due to portability concerns, especially to systems that are not
 fully standards-compliant, it is your responsibility
@@ -30723,7 +30851,7 @@ Doing so, however, is poor coding practice.
 Although the API only uses ISO C 90 features, there is an exception; the
 ``constructor'' functions use the @code{inline} keyword. If your compiler
 does not support this keyword, you should either place
-@samp{-Dinline=''} on your command line, or use the GNU Autotools and include a
+@samp{-Dinline=''} on your command line or use the GNU Autotools and include a
 @file{config.h} file in your extensions.
 
 @item
@@ -30731,21 +30859,21 @@ All pointers filled in by @command{gawk} point to memory
 managed by @command{gawk} and should be treated by the extension as
 read-only.  Memory for @emph{all} strings passed into @command{gawk}
 from the extension @emph{must} come from calling one of
-@code{gawk_malloc()}, @code{gawk_calloc()} or @code{gawk_realloc()},
+@code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()},
 and is managed by @command{gawk} from then on.
 
 @item
 The API defines several simple @code{struct}s that map values as seen
 from @command{awk}.  A value can be a @code{double}, a string, or an
 array (as in multidimensional arrays, or when creating a new array).
-String values maintain both pointer and length since embedded @value{NUL}
+String values maintain both pointer and length, because embedded @sc{nul}
 characters are allowed.
 
 @quotation NOTE
 By intent, strings are maintained using the current multibyte encoding (as
 defined by @env{LC_@var{xxx}} environment variables) and not using wide
 characters.  This matches how @command{gawk} stores strings internally
-and also how characters are likely to be input and output from files.
+and also how characters are likely to be input into and output from files.
 @end quotation
 
 @item
@@ -30763,14 +30891,14 @@ so that the extension can, e.g., print an error message
 @c The table there should be presented here
 @end itemize
 
-While you may call the API functions by using the function pointers
-directly, the interface is not so pretty. To make extension code look
+You may call the API functions by using the function pointers
+directly, but the interface is not so pretty. To make extension code look
 more like regular code, the @file{gawkapi.h} header file defines several
 macros that you should use in your code.  This @value{SECTION} presents
 the macros as if they were functions.
 
 @node General Data Types
-@subsection General Purpose Data Types
+@subsection General-Purpose Data Types
 
 @cindex Robbins, Arnold
 @cindex Ramey, Chet
@@ -30785,9 +30913,12 @@ can accommodate both love and hate.}
 @author Chet Ramey
 @end quotation
 
-The extension API defines a number of simple types and structures for general
-purpose use. Additional, more specialized, data structures are introduced
-in subsequent @value{SECTION}s, together with the functions that use them.
+The extension API defines a number of simple types and structures for
+general-purpose use. Additional, more specialized, data structures are
+introduced in subsequent @value{SECTION}s, together with the functions
+that use them.
+
+The general-purpose types and structures are as follows:
 
 @table @code
 @item typedef void *awk_ext_id_t;
@@ -30805,7 +30936,7 @@ while allowing @command{gawk} to use them as it needs to.
 @itemx @ @ @ @ awk_false = 0,
 @itemx @ @ @ @ awk_true
 @itemx @} awk_bool_t;
-A simple boolean type.
+A simple Boolean type.
 
 @item typedef struct awk_string @{
 @itemx @ @ @ @ char *str;@ @ @ @ @ @ /* data */
@@ -30814,8 +30945,9 @@ A simple boolean type.
 This represents a mutable string. @command{gawk}
 owns the memory pointed to if it supplied
 the value. Otherwise, it takes ownership of the memory pointed to.
-@strong{Such memory must come from calling one of the
-@code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()} functions!}
+@emph{Such memory must come from calling one of the
+@code{gawk_malloc()}, @code{gawk_calloc()}, or
+@code{gawk_realloc()} functions!}
 
 As mentioned earlier, strings are maintained using the current
 multibyte encoding.
@@ -30841,7 +30973,7 @@ It is used in the following @code{struct}.
 @itemx @ @ @ @ @ @ @ @ awk_value_cookie_t@ vc;
 @itemx @ @ @ @ @} u;
 @itemx @} awk_value_t;
-An ``@command{awk} value.''  
+An ``@command{awk} value.''
 The @code{val_type} member indicates what kind of value the
 @code{union} holds, and each member is of the appropriate type.
 
@@ -30850,17 +30982,18 @@ The @code{val_type} member indicates what kind of value the
 @itemx #define array_cookie@ @ @ u.a
 @itemx #define scalar_cookie@ @ u.scl
 @itemx #define value_cookie@ @ @ u.vc
-These macros make accessing the fields of the @code{awk_value_t} more
+Using these macros makes accessing the fields of the @code{awk_value_t} more
 readable.
 
 @item typedef void *awk_scalar_t;
-Scalars can be represented as an opaque type. These values are obtained from
-@command{gawk} and then passed back into it. This is discussed in a general fashion below,
-and in more detail in @ref{Symbol table by cookie}.
+Scalars can be represented as an opaque type. These values are obtained
+from @command{gawk} and then passed back into it. This is discussed
+in a general fashion in the text following this list, and in more detail in
+@ref{Symbol table by cookie}.
 
 @item typedef void *awk_value_cookie_t;
 A ``value cookie'' is an opaque type representing a cached value.
-This is also discussed in a general fashion below,
+This is also discussed in a general fashion in the text following this list,
 and in more detail in @ref{Cached values}.
 
 @end table
@@ -30870,9 +31003,9 @@ Scalar values in @command{awk} are either numbers or strings. The
 indicates what is in the @code{union}.
 
 Representing numbers is easy---the API uses a C @code{double}.  Strings
-require more work. Since @command{gawk} allows embedded @value{NUL} bytes
+require more work. Because @command{gawk} allows embedded @sc{nul} bytes
 in string values, a string must be represented as a pair containing a
-data-pointer and length. This is the @code{awk_string_t} type.
+data pointer and length. This is the @code{awk_string_t} type.
 
 Identifiers (i.e., the names of global variables) can be associated
 with either scalar values or with arrays.  In addition, @command{gawk}
@@ -30883,14 +31016,14 @@ itself be an array.  Discussion of arrays is delayed until
 The various macros listed earlier make it easier to use the elements
 of the @code{union} as if they were fields in a @code{struct}; this
 is a common coding practice in C.  Such code is easier to write and to
-read, however it remains @emph{your} responsibility to make sure that
+read, but it remains @emph{your} responsibility to make sure that
 the @code{val_type} member correctly reflects the type of the value in
-the @code{awk_value_t}.
+the @code{awk_value_t} struct.
 
 Conceptually, the first three members of the @code{union} (number, string,
 and array) are all that is needed for working with @command{awk} values.
-However, since the API provides routines for accessing and changing
-the value of global scalar variables only by using the variable's name,
+However, because the API provides routines for accessing and changing
+the value of a global scalar variable only by using the variable's name,
 there is a performance penalty: @command{gawk} must find the variable
 each time it is accessed and changed.  This turns out to be a real issue,
 not just a theoretical one.
@@ -30908,7 +31041,9 @@ See also the entry for ``Cookie'' in the @ref{Glossary}.
 object for that variable, and then use
 the cookie for getting the variable's value or for changing the variable's
 value.
-This is the @code{awk_scalar_t} type and @code{scalar_cookie} macro.
+The @code{awk_scalar_t} type holds a scalar cookie, and the
+@code{scalar_cookie} macro provides access to the value of that type
+in the @code{awk_value_t} struct.
 Given a scalar cookie, @command{gawk} can directly retrieve or
 modify the value, as required, without having to find it first.
 
@@ -30917,8 +31052,8 @@ If you know that you wish to
 use the same numeric or string @emph{value} for one or more variables,
 you can create the value once, retaining a @dfn{value cookie} for it,
 and then pass in that value cookie whenever you wish to set the value of a
-variable.  This saves both storage space within the running @command{gawk}
-process as well as the time needed to create the value.
+variable.  This saves storage space within the running @command{gawk}
+process and reduces the time needed to create the value.
 
 @node Memory Allocation Functions
 @subsection Memory Allocation Functions and Convenience Macros
@@ -30929,7 +31064,7 @@ The API provides a number of @dfn{memory allocation} functions for
 allocating memory that can be passed to @command{gawk}, as well as a number of
 convenience macros.
 This @value{SUBSECTION} presents them all as function prototypes, in
-the way that extension code would use them.
+the way that extension code would use them:
 
 @table @code
 @item void *gawk_malloc(size_t size);
@@ -30946,13 +31081,13 @@ be passed to @command{gawk}.
 
 @item void gawk_free(void *ptr);
 Call the correct version of @code{free()} to release storage that was
-allocated with @code{gawk_malloc()}, @code{gawk_calloc()} or @code{gawk_realloc()}.
+allocated with @code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()}.
 @end table
 
 The API has to provide these functions because it is possible
 for an extension to be compiled and linked against a different
 version of the C library than was used for the @command{gawk}
-executable.@footnote{This is more common on MS-Windows systems, but
+executable.@footnote{This is more common on MS-Windows systems, but it
 can happen on Unix-like systems as well.} If @command{gawk} were
 to use its version of @code{free()} when the memory came from an
 unrelated version of @code{malloc()}, unexpected behavior would
@@ -30962,7 +31097,7 @@ Two convenience macros may be used for allocating storage
 from @code{gawk_malloc()} and
 @code{gawk_realloc()}. If the allocation fails, they cause @command{gawk}
 to exit with a fatal error message.  They should be used as if they were
-procedure calls that do not return a value.
+procedure calls that do not return a value:
 
 @table @code
 @item #define emalloc(pointer, type, size, message) @dots{}
@@ -30974,7 +31109,8 @@ The arguments to this macro are as follows:
 The pointer variable to point at the allocated storage.
 
 @item type
-The type of the pointer variable, used to create a cast for the call to @code{gawk_malloc()}.
+The type of the pointer variable.  This is used to create a cast for
+the call to @code{gawk_malloc()}.
 
 @item size
 The total number of bytes to be allocated.
@@ -30998,7 +31134,7 @@ make_malloced_string(message, strlen(message), & result);
 @end example
 
 @item #define erealloc(pointer, type, size, message) @dots{}
-This is like @code{emalloc()}, but it calls @code{gawk_realloc()},
+This is like @code{emalloc()}, but it calls @code{gawk_realloc()}
 instead of @code{gawk_malloc()}.
 The arguments are the same as for the @code{emalloc()} macro.
 @end table
@@ -31009,32 +31145,32 @@ The arguments are the same as for the @code{emalloc()} macro.
 The API provides a number of @dfn{constructor} functions for creating
 string and numeric values, as well as a number of convenience macros.
 This @value{SUBSECTION} presents them all as function prototypes, in
-the way that extension code would use them.
+the way that extension code would use them:
 
 @table @code
 @item static inline awk_value_t *
-@itemx make_const_string(const char *string, size_t length, awk_value_t *result)
+@itemx make_const_string(const char *string, size_t length, awk_value_t *result);
 This function creates a string value in the @code{awk_value_t} variable
 pointed to by @code{result}. It expects @code{string} to be a C string constant
 (or other string data), and automatically creates a @emph{copy} of the data
 for storage in @code{result}. It returns @code{result}.
 
 @item static inline awk_value_t *
-@itemx make_malloced_string(const char *string, size_t length, awk_value_t *result)
+@itemx make_malloced_string(const char *string, size_t length, awk_value_t *result);
 This function creates a string value in the @code{awk_value_t} variable
 pointed to by @code{result}. It expects @code{string} to be a @samp{char *}
-value pointing to data previously obtained from @code{gawk_malloc()}, @code{gawk_calloc()} or @code{gawk_realloc()}. The idea here
+value pointing to data previously obtained from @code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()}. The idea here
 is that the data is passed directly to @command{gawk}, which assumes
 responsibility for it. It returns @code{result}.
 
 @item static inline awk_value_t *
-@itemx make_null_string(awk_value_t *result)
+@itemx make_null_string(awk_value_t *result);
 This specialized function creates a null string (the ``undefined'' value)
 in the @code{awk_value_t} variable pointed to by @code{result}.
 It returns @code{result}.
 
 @item static inline awk_value_t *
-@itemx make_number(double num, awk_value_t *result)
+@itemx make_number(double num, awk_value_t *result);
 This function simply creates a numeric value in the @code{awk_value_t} variable
 pointed to by @code{result}.
 @end table
@@ -31074,7 +31210,7 @@ The fields are:
 @table @code
 @item const char *name;
 The name of the new function.
-@command{awk} level code calls the function by this name.
+@command{awk}-level code calls the function by this name.
 This is a regular C string.
 
 Function names must obey the rules for @command{awk}
@@ -31088,8 +31224,8 @@ This is a pointer to the C function that provides the extension's
 functionality.
 The function must fill in @code{*result} with either a number
 or a string. @command{gawk} takes ownership of any string memory.
-As mentioned earlier, string memory @strong{must} come from one of @code{gawk_malloc()},
-@code{gawk_calloc()} or @code{gawk_realloc()}.
+As mentioned earlier, string memory @emph{must} come from one of
+@code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()}.
 
 The @code{num_actual_args} argument tells the C function how many
 actual parameters were passed from the calling @command{awk} code.
@@ -31124,7 +31260,7 @@ Such functions are useful if you have general ``cleanup'' tasks
 that should be performed in your extension (such as closing database
 connections or other resource deallocations).
 You can register such
-a function with @command{gawk} using the following function.
+a function with @command{gawk} using the following function:
 
 @table @code
 @item void awk_atexit(void (*funcp)(void *data, int exit_status),
@@ -31140,24 +31276,25 @@ The @code{exit_status} parameter is the exit status value that
 @command{gawk} intends to pass to the @code{exit()} system call.
 
 @item arg0
-A pointer to private data which @command{gawk} saves in order to pass to
+A pointer to private data that @command{gawk} saves in order to pass to
 the function pointed to by @code{funcp}.
 @end table
 @end table
 
-Exit callback functions are called in Last-In-First-Out (LIFO) order---that is, in
-the reverse order in which they are registered with @command{gawk}.
+Exit callback functions are called in last-in, first-out (LIFO)
+order---that is, in the reverse order in which they are registered with
+@command{gawk}.
 
 @node Extension Version String
 @subsubsection Registering An Extension Version String
 
-You can register a version string which indicates the name and
-version of your extension, with @command{gawk}, as follows:
+You can register a version string that indicates the name and
+version of your extension with @command{gawk}, as follows:
 
 @table @code
 @item void register_ext_version(const char *version);
 Register the string pointed to by @code{version} with @command{gawk}.
-@command{gawk} does @emph{not} copy the @code{version} string, so
+Note that @command{gawk} does @emph{not} copy the @code{version} string, so
 it should not be changed.
 @end table
 
@@ -31174,7 +31311,7 @@ of @code{RS} to find the end of the record, and then uses @code{FS}
 Additionally, it sets the value of @code{RT} (@pxref{Built-in Variables}).
 
 If you want, you can provide your own custom input parser.  An input
-parser's job is to return a record to the @command{gawk} record processing
+parser's job is to return a record to the @command{gawk} record-processing
 code, along with indicators for the value and length of the data to be
 used for @code{RT}, if any.
 
@@ -31182,19 +31319,19 @@ To provide an input parser, you must first provide two functions
 (where @var{XXX} is a prefix name for your extension):
 
 @table @code
-@item awk_bool_t @var{XXX}_can_take_file(const awk_input_buf_t *iobuf)
+@item awk_bool_t @var{XXX}_can_take_file(const awk_input_buf_t *iobuf);
 This function examines the information available in @code{iobuf}
 (which we discuss shortly).  Based on the information there, it
 decides if the input parser should be used for this file.
 If so, it should return true. Otherwise, it should return false.
 It should not change any state (variable values, etc.) within @command{gawk}.
 
-@item awk_bool_t @var{XXX}_take_control_of(awk_input_buf_t *iobuf)
+@item awk_bool_t @var{XXX}_take_control_of(awk_input_buf_t *iobuf);
 When @command{gawk} decides to hand control of the file over to the
 input parser, it calls this function.  This function in turn must fill
-in certain fields in the @code{awk_input_buf_t} structure, and ensure
+in certain fields in the @code{awk_input_buf_t} structure and ensure
 that certain conditions are true.  It should then return true. If an
-error of some kind occurs, it should not fill in any fields, and should
+error of some kind occurs, it should not fill in any fields and should
 return false; then @command{gawk} will not use the input parser.
 The details are presented shortly.
 @end table
@@ -31239,7 +31376,7 @@ appropriately.
 @item
 When your extension is loaded, register your input parser with
 @command{gawk} using the @code{register_input_parser()} API function
-(described below).
+(described next).
 @end enumerate
 
 An @code{awk_input_buf_t} looks like this:
@@ -31269,7 +31406,7 @@ The name of the file.
 
 @item int fd;
 A file descriptor for the file.  If @command{gawk} was able to
-open the file, then @code{fd} will @emph{not} be equal to 
+open the file, then @code{fd} will @emph{not} be equal to
 @code{INVALID_HANDLE}. Otherwise, it will.
 
 @item struct stat sbuf;
@@ -31283,15 +31420,15 @@ The decision can be made based upon @command{gawk} state (the value
 of a variable defined previously by the extension and set by
 @command{awk} code), the name of the
 file, whether or not the file descriptor is valid, the information
-in the @code{struct stat}, or any combination of the above.
+in the @code{struct stat}, or any combination of these factors.
 
 Once @code{@var{XXX}_can_take_file()} has returned true, and
 @command{gawk} has decided to use your input parser, it calls
-@code{@var{XXX}_take_control_of()}.  That function then fills one of
+@code{@var{XXX}_take_control_of()}.  That function then fills
 either the @code{get_record} field or the @code{read_func} field in
 the @code{awk_input_buf_t}.  It must also ensure that @code{fd} is @emph{not}
-set to @code{INVALID_HANDLE}.  All of the fields that may be filled by
-@code{@var{XXX}_take_control_of()} are as follows:
+set to @code{INVALID_HANDLE}.  The following list describes the fields that
+may be filled by @code{@var{XXX}_take_control_of()}:
 
 @table @code
 @item void *opaque;
@@ -31306,24 +31443,24 @@ is not required to use this pointer.
 @itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ size_t *rt_len);
 This function pointer should point to a function that creates the input
 records.  Said function is the core of the input parser.  Its behavior
-is described below.
+is described in the text following this list.
 
 @item ssize_t (*read_func)();
-This function pointer should point to function that has the
+This function pointer should point to a function that has the
 same behavior as the standard POSIX @code{read()} system call.
 It is an alternative to the @code{get_record} pointer.  Its behavior
-is also described below.
+is also described in the text following this list.
 
 @item void (*close_func)(struct awk_input *iobuf);
 This function pointer should point to a function that does
-the ``tear down.'' It should release any resources allocated by
+the ``teardown.'' It should release any resources allocated by
 @code{@var{XXX}_take_control_of()}.  It may also close the file. If it
 does so, it should set the @code{fd} field to @code{INVALID_HANDLE}.
 
 If @code{fd} is still not @code{INVALID_HANDLE} after the call to this
 function, @command{gawk} calls the regular @code{close()} system call.
 
-Having a ``tear down'' function is optional. If your input parser does
+Having a ``teardown'' function is optional. If your input parser does
 not need it, do not set this field.  Then, @command{gawk} calls the
 regular @code{close()} system call on the file descriptor, so it should
 be valid.
@@ -31334,7 +31471,7 @@ input records.  The parameters are as follows:
 
 @table @code
 @item char **out
-This is a pointer to a @code{char *} variable which is set to point
+This is a pointer to a @code{char *} variable that is set to point
 to the record.  @command{gawk} makes its own copy of the data, so
 the extension must manage this storage.
 
@@ -31353,7 +31490,7 @@ If the concept of a ``record terminator'' makes sense, then
 @code{*rt_start} should be set to point to the data to be used for
 @code{RT}, and @code{*rt_len} should be set to the length of the
 data. Otherwise, @code{*rt_len} should be set to zero.
-@code{gawk} makes its own copy of this data, so the
+@command{gawk} makes its own copy of this data, so the
 extension must manage this storage.
 @end table
 
@@ -31387,19 +31524,19 @@ set this field explicitly.
 You must choose one method or the other: either a function that
 returns a record, or one that returns raw data.  In particular,
 if you supply a function to get a record, @command{gawk} will
-call it, and never call the raw read function.
+call it, and will never call the raw read function.
 @end quotation
 
 @command{gawk} ships with a sample extension that reads directories,
-returning records for each entry in the directory (@pxref{Extension
+returning records for each entry in a directory (@pxref{Extension
 Sample Readdir}).  You may wish to use that code as a guide for writing
 your own input parser.
 
 When writing an input parser, you should think about (and document)
 how it is expected to interact with @command{awk} code.  You may want
-it to always be called, and take effect as appropriate (as the
+it to always be called, and to take effect as appropriate (as the
 @code{readdir} extension does).  Or you may want it to take effect
-based upon the value of an @code{awk} variable, as the XML extension
+based upon the value of an @command{awk} variable, as the XML extension
 from the @code{gawkextlib} project does (@pxref{gawkextlib}).
 In the latter case, code in a @code{BEGINFILE} section
 can look at @code{FILENAME} and @code{ERRNO} to decide whether or
@@ -31450,7 +31587,7 @@ values, etc.) within @command{gawk}.
 The function pointed to by this field is called when @command{gawk}
 decides to let the output wrapper take control of the file. It should
 fill in appropriate members of the @code{awk_output_buf_t} structure,
-as described below, and return true if successful, false otherwise.
+as described next, and return true if successful, false otherwise.
 
 @item awk_const struct output_wrapper *awk_const next;
 This is for use by @command{gawk};
@@ -31507,7 +31644,7 @@ a pointer to any private data associated with the file.
 These pointers should be set to point to functions that perform
 the equivalent function as the @code{<stdio.h>} functions do, if appropriate.
 @command{gawk} uses these function pointers for all output.
-@command{gawk} initializes the pointers to point to internal, ``pass through''
+@command{gawk} initializes the pointers to point to internal ``pass-through''
 functions that just call the regular @code{<stdio.h>} functions, so an
 extension only needs to redefine those functions that are appropriate for
 what it does.
@@ -31518,7 +31655,7 @@ upon the @code{name} and @code{mode} fields, and any additional state
 (such as @command{awk} variable values) that is appropriate.
 
 When @command{gawk} calls @code{@var{XXX}_take_control_of()}, that function should fill
-in the other fields, as appropriate, except for @code{fp}, which it should just
+in the other fields as appropriate, except for @code{fp}, which it should just
 use normally.
 
 You register your output wrapper with the following function:
@@ -31558,14 +31695,14 @@ The fields are as follows:
 The name of the two-way processor.
 
 @item awk_bool_t (*can_take_two_way)(const char *name);
-This function returns true if it wants to take over two-way I/O for this @value{FN}.
+The function pointed to by this field should return true if it wants to take over two-way I/O for this @value{FN}.
 It should not change any state (variable
 values, etc.) within @command{gawk}.
 
 @item awk_bool_t (*take_control_of)(const char *name,
 @itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ awk_input_buf_t *inbuf,
 @itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ awk_output_buf_t *outbuf);
-This function should fill in the @code{awk_input_buf_t} and
+The function pointed to by this field should fill in the @code{awk_input_buf_t} and
 @code{awk_outut_buf_t} structures pointed to by @code{inbuf} and
 @code{outbuf}, respectively.  These structures were described earlier.
 
@@ -31593,9 +31730,9 @@ Register the two-way processor pointed to by @code{two_way_processor} with
 @cindex messages from extensions
 
 You can print different kinds of warning messages from your
-extension, as described below.  Note that for these functions,
-you must pass in the extension id received from @command{gawk}
-when the extension was loaded.@footnote{Because the API uses only ISO C 90
+extension, as described here.  Note that for these functions,
+you must pass in the extension ID received from @command{gawk}
+when the extension was loaded:@footnote{Because the API uses only ISO C 90
 features, it cannot make use of the ISO C 99 variadic macro feature to hide
 that parameter. More's the pity.}
 
@@ -31647,12 +31784,12 @@ matches what you requested, the function returns true and fills
 in the @code{awk_value_t} result.
 Otherwise, the function returns false, and the @code{val_type}
 member indicates the type of the actual value.  You may then
-print an error message, or reissue the request for the actual
+print an error message or reissue the request for the actual
 value type, as appropriate.  This behavior is summarized in
 @ref{table-value-types-returned}.
 
 @float Table,table-value-types-returned
-@caption{API Value Types Returned}
+@caption{API value types returned}
 @docbook
 <informaltable>
 <tgroup cols="6">
@@ -31664,7 +31801,7 @@ value type, as appropriate.  This behavior is summarized in
   <colspec colwidth="16.6*" colname="c6"/>
   <spanspec spanname="hspan" namest="c3" nameend="c6" align="center"/>
   <thead>
-    <row><entry></entry><entry spanname="hspan"><para>Type of Actual Value:</para></entry></row>
+    <row><entry></entry><entry spanname="hspan"><para>Type of Actual Value</para></entry></row>
     <row>
       <entry></entry>
       <entry></entry>
@@ -31680,32 +31817,32 @@ value type, as appropriate.  This behavior is summarized in
       <entry><para><emphasis role="bold">String</emphasis></para></entry>
       <entry><para>String</para></entry>
       <entry><para>String</para></entry>
-      <entry><para>false</para></entry>
-      <entry><para>false</para></entry>
+      <entry><para>False</para></entry>
+      <entry><para>False</para></entry>
     </row>
     <row>
       <entry></entry>
       <entry><para><emphasis role="bold">Number</emphasis></para></entry>
       <entry><para>Number if can be converted, else false</para></entry>
       <entry><para>Number</para></entry>
-      <entry><para>false</para></entry>
-      <entry><para>false</para></entry>
+      <entry><para>False</para></entry>
+      <entry><para>False</para></entry>
     </row>
     <row>
       <entry><para><emphasis role="bold">Type</emphasis></para></entry>
       <entry><para><emphasis role="bold">Array</emphasis></para></entry>
-      <entry><para>false</para></entry>
-      <entry><para>false</para></entry>
+      <entry><para>False</para></entry>
+      <entry><para>False</para></entry>
       <entry><para>Array</para></entry>
-      <entry><para>false</para></entry>
+      <entry><para>False</para></entry>
     </row>
     <row>
-      <entry><para><emphasis role="bold">Requested:</emphasis></para></entry>
+      <entry><para><emphasis role="bold">Requested</emphasis></para></entry>
       <entry><para><emphasis role="bold">Scalar</emphasis></para></entry>
       <entry><para>Scalar</para></entry>
       <entry><para>Scalar</para></entry>
-      <entry><para>false</para></entry>
-      <entry><para>false</para></entry>
+      <entry><para>False</para></entry>
+      <entry><para>False</para></entry>
     </row>
     <row>
       <entry></entry>
@@ -31717,11 +31854,11 @@ value type, as appropriate.  This behavior is summarized in
     </row>
     <row>
       <entry></entry>
-      <entry><para><emphasis role="bold">Value Cookie</emphasis></para></entry>
-      <entry><para>false</para></entry>
-      <entry><para>false</para></entry>
-      <entry><para>false</para>
-      </entry><entry><para>false</para></entry>
+      <entry><para><emphasis role="bold">Value cookie</emphasis></para></entry>
+      <entry><para>False</para></entry>
+      <entry><para>False</para></entry>
+      <entry><para>False</para>
+      </entry><entry><para>False</para></entry>
     </row>
   </tbody>
 </tgroup>
@@ -31731,7 +31868,7 @@ value type, as appropriate.  This behavior is summarized in
 @ifnotplaintext
 @ifnotdocbook
 @multitable @columnfractions .50 .50
-@headitem @tab Type of Actual Value:
+@headitem @tab Type of Actual Value
 @end multitable
 @c 10/2014: Thanks to Karl Berry for this bit to reduce the space:
 @tex
@@ -31739,12 +31876,12 @@ value type, as appropriate.  This behavior is summarized in
 @end tex
 @multitable @columnfractions .166 .166 .198 .15 .15 .166
 @headitem @tab @tab String @tab Number @tab Array @tab Undefined
-@item @tab @b{String} @tab String @tab String @tab false @tab false
-@item @tab @b{Number} @tab Number if can be converted, else false @tab Number @tab false @tab false
-@item @b{Type} @tab @b{Array} @tab false @tab false @tab Array @tab false
-@item @b{Requested:} @tab @b{Scalar} @tab Scalar @tab Scalar @tab false @tab false
+@item @tab @b{String} @tab String @tab String @tab False @tab False
+@item @tab @b{Number} @tab Number if can be converted, else false @tab Number @tab False @tab False
+@item @b{Type} @tab @b{Array} @tab False @tab False @tab Array @tab False
+@item @b{Requested} @tab @b{Scalar} @tab Scalar @tab Scalar @tab False @tab False
 @item @tab @b{Undefined} @tab String @tab Number @tab Array @tab Undefined
-@item @tab @b{Value Cookie} @tab false @tab false @tab false @tab false
+@item @tab @b{Value cookie} @tab False @tab False @tab False @tab False
 @end multitable
 @end ifnotdocbook
 @end ifnotplaintext
@@ -31755,21 +31892,21 @@ value type, as appropriate.  This behavior is summarized in
                         +------------+------------+-----------+-----------+
                         |   String   |   Number   | Array     | Undefined |
 +-----------+-----------+------------+------------+-----------+-----------+
-|           | String    |   String   |   String   | false     | false     |
+|           | String    |   String   |   String   | False     | False     |
 |           |-----------+------------+------------+-----------+-----------+
-|           | Number    | Number if  |   Number   | false     | false     |
+|           | Number    | Number if  |   Number   | False     | False     |
 |           |           | can be     |            |           |           |
 |           |           | converted, |            |           |           |
 |           |           | else false |            |           |           |
 |           |-----------+------------+------------+-----------+-----------+
-|   Type    | Array     |   false    |   false    | Array     | false     |
+|   Type    | Array     |   False    |   False    | Array     | False     |
 | Requested |-----------+------------+------------+-----------+-----------+
-|           | Scalar    |   Scalar   |   Scalar   | false     | false     |
+|           | Scalar    |   Scalar   |   Scalar   | False     | False     |
 |           |-----------+------------+------------+-----------+-----------+
 |           | Undefined |  String    |   Number   | Array     | Undefined |
 |           |-----------+------------+------------+-----------+-----------+
-|           | Value     |   false    |   false    | false     | false     |
-|           | Cookie    |            |            |           |           |
+|           | Value     |   False    |   False    | False     | False     |
+|           | cookie    |            |            |           |           |
 +-----------+-----------+------------+------------+-----------+-----------+
 @end example
 @end ifplaintext
@@ -31786,17 +31923,17 @@ passed to your extension function. They are:
 @itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ awk_valtype_t wanted,
 @itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ awk_value_t *result);
 Fill in the @code{awk_value_t} structure pointed to by @code{result}
-with the @code{count}'th argument.  Return true if the actual
-type matches @code{wanted}, false otherwise.  In the latter
+with the @code{count}th argument.  Return true if the actual
+type matches @code{wanted}, and false otherwise.  In the latter
 case, @code{result@w{->}val_type} indicates the actual type
-(@pxref{table-value-types-returned}).  Counts are zero based---the first
+(@pxref{table-value-types-returned}).  Counts are zero-based---the first
 argument is numbered zero, the second one, and so on. @code{wanted}
 indicates the type of value expected.
 
 @item awk_bool_t set_argument(size_t count, awk_array_t array);
 Convert a parameter that was undefined into an array; this provides
-call-by-reference for arrays.  Return false if @code{count} is too big,
-or if the argument's type is not undefined.  @xref{Array Manipulation},
+call by reference for arrays.  Return false if @code{count} is too big,
+or if the argument's type is not undefined.  @DBXREF{Array Manipulation}
 for more information on creating arrays.
 @end table
 
@@ -31819,8 +31956,9 @@ allows you to create and release cached values.
 The following routines provide the ability to access and update
 global @command{awk}-level variables by name.  In compiler terminology,
 identifiers of different kinds are termed @dfn{symbols}, thus the ``sym''
-in the routines' names.  The data structure which stores information
+in the routines' names.  The data structure that stores information
 about symbols is termed a @dfn{symbol table}.
+The functions are as follows:
 
 @table @code
 @item awk_bool_t sym_lookup(const char *name,
@@ -31829,14 +31967,14 @@ about symbols is termed a @dfn{symbol table}.
 Fill in the @code{awk_value_t} structure pointed to by @code{result}
 with the value of the variable named by the string @code{name}, which is
 a regular C string.  @code{wanted} indicates the type of value expected.
-Return true if the actual type matches @code{wanted}, false otherwise.
+Return true if the actual type matches @code{wanted}, and false otherwise.
 In the latter case, @code{result->val_type} indicates the actual type
 (@pxref{table-value-types-returned}).
 
 @item awk_bool_t sym_update(const char *name, awk_value_t *value);
 Update the variable named by the string @code{name}, which is a regular
 C string.  The variable is added to @command{gawk}'s symbol table
-if it is not there.  Return true if everything worked, false otherwise.
+if it is not there.  Return true if everything worked, and false otherwise.
 
 Changing types (scalar to array or vice versa) of an existing variable
 is @emph{not} allowed, nor may this routine be used to update an array.
@@ -31851,7 +31989,7 @@ cannot change any of those variables.
 @quotation CAUTION
 It is possible for the lookup of @code{PROCINFO} to fail. This happens if
 the @command{awk} program being run does not reference @code{PROCINFO};
-in this case @command{gawk} doesn't bother to create the array and
+in this case, @command{gawk} doesn't bother to create the array and
 populate it.
 @end quotation
 
@@ -31863,7 +32001,7 @@ to a global variable or array. It is an optimization that
 avoids looking up variables in @command{gawk}'s symbol table every time
 access is needed. This was discussed earlier, in @ref{General Data Types}.
 
-The following functions let you work with scalar cookies.
+The following functions let you work with scalar cookies:
 
 @table @code
 @item awk_bool_t sym_lookup_scalar(awk_scalar_t cookie,
@@ -31908,18 +32046,21 @@ do_magic(int nargs, awk_value_t *result)
 @noindent
 This code looks (and is) simple and straightforward. So what's the problem?
 
-Consider what happens if @command{awk}-level code associated with your
-extension calls the @code{magic()} function (implemented in C by @code{do_magic()}),
-once per record, while processing hundreds of thousands or millions of records.
-The @code{MAGIC_VAR} variable is looked up in the symbol table once or twice per function call!
+Well, consider what happens if @command{awk}-level code associated
+with your extension calls the @code{magic()} function (implemented in
+C by @code{do_magic()}), once per record, while processing hundreds
+of thousands or millions of records.  The @code{MAGIC_VAR} variable is
+looked up in the symbol table once or twice per function call!
 
-The symbol table lookup is really pure overhead; it is considerably more efficient
-to get a cookie that represents the variable, and use that to get the variable's
-value and update it as needed.@footnote{The difference is measurable and quite real. Trust us.}
+The symbol table lookup is really pure overhead; it is considerably
+more efficient to get a cookie that represents the variable, and use
+that to get the variable's value and update it as needed.@footnote{The
+difference is measurable and quite real. Trust us.}
 
-Thus, the way to use cookies is as follows.  First, install your extension's variable
-in @command{gawk}'s symbol table using @code{sym_update()}, as usual. Then get a
-scalar cookie for the variable using @code{sym_lookup()}:
+Thus, the way to use cookies is as follows.  First, install
+your extension's variable in @command{gawk}'s symbol table using
+@code{sym_update()}, as usual. Then get a scalar cookie for the variable
+using @code{sym_lookup()}:
 
 @example
 static awk_scalar_t magic_var_cookie;    /* cookie for MAGIC_VAR */
@@ -31974,7 +32115,7 @@ and carefully check the return values from the API functions.
 @subsubsection Creating and Using Cached Values
 
 The routines in this section allow you to create and release
-cached values.  As with scalar cookies, in theory, cached values
+cached values.  Like scalar cookies, in theory, cached values
 are not necessary. You can create numbers and strings using
 the functions in @ref{Constructor Functions}. You can then
 assign those values to variables using @code{sym_update()}
@@ -31982,7 +32123,7 @@ or @code{sym_update_scalar()}, as you like.
 
 However, you can understand the point of cached values if you remember that
 @emph{every} string value's storage @emph{must} come from @code{gawk_malloc()},
-@code{gawk_calloc()} or @code{gawk_realloc()}.
+@code{gawk_calloc()}, or @code{gawk_realloc()}.
 If you have 20 variables, all of which have the same string value, you
 must create 20 identical copies of the string.@footnote{Numeric values
 are clearly less problematic, requiring only a C @code{double} to store.}
@@ -31993,11 +32134,11 @@ is what the routines in this section let you do.  The functions are as follows:
 
 @table @code
 @item awk_bool_t create_value(awk_value_t *value, awk_value_cookie_t *result);
-Create a cached string or numeric value from @code{value} for efficient later
-assignment.
-Only values of type @code{AWK_NUMBER} and @code{AWK_STRING} are allowed.  Any other type
-is rejected.  While @code{AWK_UNDEFINED} could be allowed, doing so would
-result in inferior performance.
+Create a cached string or numeric value from @code{value} for
+efficient later assignment.  Only values of type @code{AWK_NUMBER}
+and @code{AWK_STRING} are allowed.  Any other type is rejected.
+@code{AWK_UNDEFINED} could be allowed, but doing so would result in
+inferior performance.
 
 @item awk_bool_t release_value(awk_value_cookie_t vc);
 Release the memory associated with a value cookie obtained
@@ -32018,7 +32159,7 @@ my_extension_init()
     size_t long_string_len;
 
     /* code from earlier */
-    @dots{} 
+    @dots{}
     /* @dots{} fill in long_string and long_string_len @dots{} */
     make_malloced_string(long_string, long_string_len, & value);
     create_value(& value, & answer_cookie);    /* create cookie */
@@ -32048,11 +32189,11 @@ do_magic(int nargs, awk_value_t *result)
 @end example
 
 @noindent
-Using value cookies in this way saves considerable storage, since all of
+Using value cookies in this way saves considerable storage, as all of
 @code{VAR1} through @code{VAR100} share the same value.
 
 You might be wondering, ``Is this sharing problematic?
-What happens if @command{awk} code assigns a new value to @code{VAR1},
+What happens if @command{awk} code assigns a new value to @code{VAR1};
 are all the others changed too?''
 
 That's a great question. The answer is that no, it's not a problem.
@@ -32070,7 +32211,7 @@ you should release any cached values that you created, using
 @subsection Array Manipulation
 @cindex array manipulation in extensions
 
-The primary data structure@footnote{Okay, the only data structure.} in @command{awk}
+The primary data structure@footnote{OK, the only data structure.} in @command{awk}
 is the associative array (@pxref{Arrays}).
 Extensions need to be able to manipulate @command{awk} arrays.
 The API provides a number of data structures for working with arrays,
@@ -32091,7 +32232,7 @@ both work with and create true arrays of arrays (@pxref{General Data Types}).
 @node Array Data Types
 @subsubsection Array Data Types
 
-The data types associated with arrays are listed below.
+The data types associated with arrays are as follows:
 
 @table @code
 @item typedef void *awk_array_t;
@@ -32156,7 +32297,7 @@ modify them.
 @node Array Functions
 @subsubsection Array Functions
 
-The following functions relate to individual array elements.
+The following functions relate to individual array elements:
 
 @table @code
 @item awk_bool_t get_element_count(awk_array_t a_cookie, size_t *count);
@@ -32175,13 +32316,13 @@ Return false if @code{wanted} does not match the actual type or if
 @code{index} is not in the array (@pxref{table-value-types-returned}).
 
 The value for @code{index} can be numeric, in which case @command{gawk}
-converts it to a string. Using non-integral values is possible, but
+converts it to a string. Using nonintegral values is possible, but
 requires that you understand how such values are converted to strings
-(@pxref{Conversion}); thus using integral values is safest.
+(@pxref{Conversion}); thus, using integral values is safest.
 
-As with @emph{all} strings passed into @code{gawk} from an extension,
+As with @emph{all} strings passed into @command{gawk} from an extension,
 the string value of @code{index} must come from @code{gawk_malloc()},
-@code{gawk_calloc()} or @code{gawk_realloc()}, and
+@code{gawk_calloc()}, or @code{gawk_realloc()}, and
 @command{gawk} releases the storage.
 
 @item awk_bool_t set_array_element(awk_array_t a_cookie,
@@ -32210,7 +32351,7 @@ The following functions relate to arrays as a whole:
 @table @code
 @item awk_array_t create_array(void);
 Create a new array to which elements may be added.
-@xref{Creating Arrays}, for a discussion of how to
+@DBXREF{Creating Arrays} for a discussion of how to
 create a new array and add elements to it.
 
 @item awk_bool_t clear_array(awk_array_t a_cookie);
@@ -32237,7 +32378,7 @@ flatten an array and work with it.
 @item awk_bool_t release_flattened_array(awk_array_t a_cookie,
 @itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ awk_flat_array_t *data);
 When done with a flattened array, release the storage using this function.
-You must pass in both the original array cookie, and the address of
+You must pass in both the original array cookie and the address of
 the created @code{awk_flat_array_t} structure.
 The function returns true upon success, false otherwise.
 @end table
@@ -32245,9 +32386,9 @@ The function returns true upon success, false otherwise.
 @node Flattening Arrays
 @subsubsection Working With All The Elements of an Array
 
-To @dfn{flatten} an array is create a structure that
+To @dfn{flatten} an array is to create a structure that
 represents the full array in a fashion that makes it easy
-for C code to traverse the entire array.  Test code
+for C code to traverse the entire array.  Some of the code
 in @file{extension/testext.c} does this, and also serves
 as a nice example showing how to use the APIs.
 
@@ -32304,9 +32445,9 @@ dump_array_and_delete(int nargs, awk_value_t *result)
 @end example
 
 The function then proceeds in steps, as follows. First, retrieve
-the name of the array, passed as the first argument. Then
-retrieve the array itself. If either operation fails, print
-error messages and return:
+the name of the array, passed as the first argument, followed by
+the array itself. If either operation fails, print an
+error message and return:
 
 @example
     /* get argument named array as flat array and print it */
@@ -32342,7 +32483,7 @@ and print it:
 @end example
 
 The third step is to actually flatten the array, and then
-to double check that the count in the @code{awk_flat_array_t}
+to double-check that the count in the @code{awk_flat_array_t}
 is the same as the count just retrieved:
 
 @example
@@ -32363,7 +32504,7 @@ is the same as the count just retrieved:
 The fourth step is to retrieve the index of the element
 to be deleted, which was passed as the second argument.
 Remember that argument counts passed to @code{get_argument()}
-are zero-based, thus the second argument is numbered one:
+are zero-based, and thus the second argument is numbered one:
 
 @example
     if (! get_argument(1, AWK_STRING, & value3)) @{
@@ -32378,7 +32519,7 @@ element values. In addition, upon finding the element with the
 index that is supposed to be deleted, the function sets the
 @code{AWK_ELEMENT_DELETE} bit in the @code{flags} field
 of the element.  When the array is released, @command{gawk}
-traverses the flattened array, and deletes any elements which
+traverses the flattened array, and deletes any elements that
 have this flag bit set:
 
 @example
@@ -32413,7 +32554,7 @@ code) once you have called @code{release_flattened_array()}:
     @}
 @end example
 
-Finally, since everything was successful, the function sets the
+Finally, because everything was successful, the function sets the
 return value to success, and returns:
 
 @example
@@ -32448,7 +32589,7 @@ code can access them and manipulate them.
 
 There are two important points about creating arrays from extension code:
 
-@enumerate 1
+@itemize @value{BULLET}
 @item
 You must install a new array into @command{gawk}'s symbol
 table immediately upon creating it.  Once you have done so,
@@ -32470,7 +32611,7 @@ using @code{sym_update()}, or install it as an element in a previously
 existing array using @code{set_array_element()}.  We show example code shortly.
 
 @item
-Due to gawk internals, after using @code{sym_update()} to install an array
+Due to @command{gawk} internals, after using @code{sym_update()} to install an array
 into @command{gawk}, you have to retrieve the array cookie from the value
 passed in to @command{sym_update()} before doing anything else with it, like so:
 
@@ -32490,7 +32631,7 @@ new_array = val.array_cookie;    /* YOU MUST DO THIS */
 
 If installing an array as a subarray, you must also retrieve the value
 of the array cookie after the call to @code{set_element()}.
-@end enumerate
+@end itemize
 
 The following C code is a simple test extension to create an array
 with two regular elements and with a subarray. The leading @code{#include}
@@ -32609,7 +32750,7 @@ dl_load_func(func_table, testarray, "")
 @end ignore
 @end example
 
-Here is sample script that loads the extension
+Here is a sample script that loads the extension
 and then dumps the array:
 
 @example
@@ -32639,9 +32780,78 @@ $ @kbd{AWKLIBPATH=$PWD ./gawk -f subarray.awk}
 @end example
 
 @noindent
-(@xref{Finding Extensions}, for more information on the
+(@DBXREF{Finding Extensions} for more information on the
 @env{AWKLIBPATH} environment variable.)
 
+@node Redirection API
+@subsection Accessing and Manipulating Redirections
+
+The following function allows extensions to access and manipulate redirections.
+
+@table @code
+@item awk_bool_t get_file(const char *name,
+@itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ size_t name_len,
+@itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ const char *filetype,
+@itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ int fd,
+@itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ const awk_input_buf_t **ibufp,
+@itemx @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ const awk_output_buf_t **obufp);
+Look up a file in @command{gawk}'s internal redirection table.
+If @code{name} is @code{NULL} or @code{name_len} is zero, return
+data for the currently open input file corresponding to @code{FILENAME}.
+(This does not access the @code{filetype} argument, so that may be undefined).  
+If the file is not already open, attempt to open it.
+The @code{filetype} argument must be zero-terminated and should be one of:
+
+@table @code
+@item ">"
+A file opened for output.
+
+@item ">>"
+A file opened for append.
+
+@item "<"
+A file opened for input.
+
+@item "|>"
+A pipe opened for output.
+
+@item "|<"
+A pipe opened for input.
+
+@item "|&"
+A two-way coprocess.
+@end table
+
+On error, return a @code{false} value.  Otherwise, return
+@code{true}, and return additional information about the redirection
+in the @code{ibufp} and @code{obufp} pointers.  For input
+redirections, the @code{*ibufp} value should be non-@code{NULL},
+and @code{*obufp} should be @code{NULL}.  For output redirections,
+the @code{*obufp} value should be non-@code{NULL}, and @code{*ibufp}
+should be @code{NULL}.  For two-way coprocesses, both values should
+be non-@code{NULL}.
+
+In the usual case, the extension is interested in @code{(*ibufp)->fd}
+and/or @code{fileno((*obufp)->fp)}.  If the file is not already
+open, and the @code{fd} argument is non-negative, @command{gawk}
+will use that file descriptor instead of opening the file in the
+usual way.  If @code{fd} is non-negative, but the file exists already,
+@command{gawk} ignores @code{fd} and returns the existing file.  It is
+the caller's responsibility to notice that neither the @code{fd} in
+the returned @code{awk_input_buf_t} nor the @code{fd} in the returned
+@code{awk_output_buf_t} matches the requested value.
+
+Note that supplying a file descriptor is currently @emph{not} supported
+for pipes.  However, supplying a file descriptor should work for input,
+output, append, and two-way (coprocess) sockets.  If @code{filetype}
+is two-way, @command{gawk} assumes that it is a socket!  Note that in
+the two-way case, the input and output file descriptors may differ.
+To check for success, you must check whether either matches.
+@end table
+
+It is anticipated that this API function will be used to implement I/O
+multiplexing and a socket library.
+
 @node Extension API Variables
 @subsection API Variables
 
@@ -32666,10 +32876,10 @@ The API versions are available at compile time as constants:
 
 @table @code
 @item GAWK_API_MAJOR_VERSION
-The major version of the API.
+The major version of the API
 
 @item GAWK_API_MINOR_VERSION
-The minor version of the API.
+The minor version of the API
 @end table
 
 The minor version increases when new functions are added to the API. Such
@@ -32687,14 +32897,14 @@ constant integers:
 
 @table @code
 @item api->major_version
-The major version of the running @command{gawk}.
+The major version of the running @command{gawk}
 
 @item api->minor_version
-The minor version of the running @command{gawk}.
+The minor version of the running @command{gawk}
 @end table
 
 It is up to the extension to decide if there are API incompatibilities.
-Typically a check like this is enough:
+Typically, a check like this is enough:
 
 @example
 if (api->major_version != GAWK_API_MAJOR_VERSION
@@ -32708,7 +32918,7 @@ if (api->major_version != GAWK_API_MAJOR_VERSION
 @end example
 
 Such code is included in the boilerplate @code{dl_load_func()} macro
-provided in @file{gawkapi.h} (discussed later, in
+provided in @file{gawkapi.h} (discussed in
 @ref{Extension API Boilerplate}).
 
 @node Extension API Informational Variables
@@ -32725,8 +32935,7 @@ whether the corresponding command-line options were enabled when
 This variable is true if @command{gawk} was invoked with @option{--debug} option.
 
 @item do_lint
-This variable is true if @command{gawk} was invoked with @option{--lint} option
-(@pxref{Options}).
+This variable is true if @command{gawk} was invoked with @option{--lint} option.
 
 @item do_mpfr
 This variable is true if @command{gawk} was invoked with @option{--bignum} option.
@@ -32751,12 +32960,12 @@ The others should not change during execution.
 As mentioned earlier (@pxref{Extension Mechanism Outline}), the function
 definitions as presented are really macros. To use these macros, your
 extension must provide a small amount of boilerplate code (variables and
-functions) towards the top of your source file, using pre-defined names
-as described below.  The boilerplate needed is also provided in comments
+functions) toward the top of your source file, using predefined names
+as described here.  The boilerplate needed is also provided in comments
 in the @file{gawkapi.h} header file:
 
 @example
-/* Boiler plate code: */
+/* Boilerplate code: */
 int plugin_is_GPL_compatible;
 
 static gawk_api_t *const api;
@@ -32815,7 +33024,7 @@ to @code{NULL}, or to point to a string giving the name and version of
 your extension.
 
 @item static awk_ext_func_t func_table[] = @{ @dots{} @};
-This is an array of one or more @code{awk_ext_func_t} structures
+This is an array of one or more @code{awk_ext_func_t} structures,
 as described earlier (@pxref{Extension Functions}).
 It can then be looped over for multiple calls to
 @code{add_ext_func()}.
@@ -32840,7 +33049,7 @@ This macro expands to a @code{dl_load()} function that performs
 all the necessary initializations.
 @end table
 
-The point of the all the variables and arrays is to let the
+The point of all the variables and arrays is to let the
 @code{dl_load()} function (from the @code{dl_load_func()}
 macro) do all the standard work. It does the following:
 
@@ -32875,7 +33084,7 @@ Compiled extensions have to be installed in a directory where
 built in the default fashion, the directory in which to find
 extensions is @file{/usr/local/lib/gawk}.  You can also specify a search
 path with a list of directories to search for compiled extensions.
-@xref{AWKLIBPATH Variable}, for more information.
+@DBXREF{AWKLIBPATH Variable} for more information.
 
 @node Extension Example
 @section Example: Some File Functions
@@ -32883,7 +33092,7 @@ path with a list of directories to search for compiled extensions.
 
 @quotation
 @i{No matter where you go, there you are.}
-@author Buckaroo Bonzai
+@author Buckaroo Banzai
 @end quotation
 
 @c It's enough to show chdir and stat, no need for fts
@@ -32946,7 +33155,7 @@ the @code{stat()} fails.  It fills in the following elements:
 
 @table @code
 @item "name"
-The name of the file that was @code{stat()}'ed.
+The name of the file that was @code{stat()}ed.
 
 @item "dev"
 @itemx "ino"
@@ -33002,7 +33211,7 @@ interprocess communications).
 The file is a directory.
 
 @item "fifo"
-The file is a named-pipe (also known as a FIFO).
+The file is a named pipe (also known as a FIFO).
 
 @item "file"
 The file is just a regular file.
@@ -33025,7 +33234,7 @@ For some other systems, @dfn{a priori} knowledge is used to provide
 a value. Where no value can be determined, it defaults to 512.
 @end table
 
-Several additional elements may be present depending upon the operating
+Several additional elements may be present, depending upon the operating
 system and the type of the file.  You can test for them in your @command{awk}
 program by using the @code{in} operator
 (@pxref{Reference to Elements}):
@@ -33055,10 +33264,10 @@ edited slightly for presentation.  See @file{extension/filefuncs.c}
 in the @command{gawk} distribution for the complete version.}
 
 The file includes a number of standard header files, and then includes
-the @file{gawkapi.h} header file which provides the API definitions.
-Those are followed by the necessary variable declarations 
+the @file{gawkapi.h} header file, which provides the API definitions.
+Those are followed by the necessary variable declarations
 to make use of the API macros and boilerplate code
-(@pxref{Extension API Boilerplate}).
+(@pxref{Extension API Boilerplate}):
 
 @example
 #ifdef HAVE_CONFIG_H
@@ -33096,10 +33305,10 @@ int plugin_is_GPL_compatible;
 @cindex programming conventions, @command{gawk} extensions
 By convention, for an @command{awk} function @code{foo()}, the C function
 that implements it is called @code{do_foo()}.  The function should have
-two arguments: the first is an @code{int} usually called @code{nargs},
+two arguments. The first is an @code{int}, usually called @code{nargs},
 that represents the number of actual arguments for the function.
-The second is a pointer to an @code{awk_value_t}, usually named
-@code{result}.
+The second is a pointer to an @code{awk_value_t} structure, usually named
+@code{result}:
 
 @example
 /*  do_chdir --- provide dynamically loaded chdir() function for gawk */
@@ -33119,13 +33328,13 @@ do_chdir(int nargs, awk_value_t *result)
 @end example
 
 The @code{newdir}
-variable represents the new directory to change to, retrieved
+variable represents the new directory to change to, which is retrieved
 with @code{get_argument()}.  Note that the first argument is
 numbered zero.
 
 If the argument is retrieved successfully, the function calls the
 @code{chdir()} system call. If the @code{chdir()} fails, @code{ERRNO}
-is updated.
+is updated:
 
 @example
     if (get_argument(0, AWK_STRING, & newdir)) @{
@@ -33144,7 +33353,7 @@ Finally, the function returns the return value to the @command{awk} level:
 
 The @code{stat()} extension is more involved.  First comes a function
 that turns a numeric mode into a printable representation
-(e.g., 644 becomes @samp{-rw-r--r--}). This is omitted here for brevity:
+(e.g., octal @code{0644} becomes @samp{-rw-r--r--}). This is omitted here for brevity:
 
 @example
 /* format_mode --- turn a stat mode field into something readable */
@@ -33200,9 +33409,9 @@ array_set_numeric(awk_array_t array, const char *sub, double num)
 
 The following function does most of the work to fill in
 the @code{awk_array_t} result array with values obtained
-from a valid @code{struct stat}. It is done in a separate function
+from a valid @code{struct stat}. This work is done in a separate function
 to support the @code{stat()} function for @command{gawk} and also
-to support the @code{fts()} extension which is included in
+to support the @code{fts()} extension, which is included in
 the same file but whose code is not shown here
 (@pxref{Extension Sample File Functions}).
 
@@ -33323,10 +33532,10 @@ the @code{stat()} system call instead of the @code{lstat()} system
 call.  This is done by using a function pointer: @code{statfunc}.
 @code{statfunc} is initialized to point to @code{lstat()} (instead
 of @code{stat()}) to get the file information, in case the file is a
-symbolic link. However, if there were three arguments, @code{statfunc}
-is set point to @code{stat()}, instead.
+symbolic link. However, if the third argument is included, @code{statfunc}
+is set to point to @code{stat()}, instead.
 
-Here is the @code{do_stat()} function. It starts with
+Here is the @code{do_stat()} function, which starts with
 variable declarations and argument checking:
 
 @ignore
@@ -33380,7 +33589,7 @@ Next, it gets the information for the file.  If the called function
     /* always empty out the array */
     clear_array(array);
 
-    /* stat the file, if error, set ERRNO and return */
+    /* stat the file; if error, set ERRNO and return */
     ret = statfunc(name, & sbuf);
     if (ret < 0) @{
         update_ERRNO_int(errno);
@@ -33402,7 +33611,9 @@ Finally, it's necessary to provide the ``glue'' that loads the
 new function(s) into @command{gawk}.
 
 The @code{filefuncs} extension also provides an @code{fts()}
-function, which we omit here. For its sake there is an initialization
+function, which we omit here
+(@pxref{Extension Sample File Functions}).
+For its sake, there is an initialization
 function:
 
 @example
@@ -33441,7 +33652,7 @@ dl_load_func(func_table, filefuncs, "")
 And that's it!
 
 @node Using Internal File Ops
-@subsection Integrating The Extensions
+@subsection Integrating the Extensions
 
 @cindex @command{gawk}, interpreter@comma{} adding code to
 Now that the code is written, it must be possible to add it at
@@ -33450,9 +33661,9 @@ code must be compiled.  Assuming that the functions are in
 a file named @file{filefuncs.c}, and @var{idir} is the location
 of the @file{gawkapi.h} header file,
 the following steps@footnote{In practice, you would probably want to
-use the GNU Autotools---Automake, Autoconf, Libtool, and @command{gettext}---to
+use the GNU Autotools (Automake, Autoconf, Libtool, and @command{gettext}) to
 configure and build your libraries. Instructions for doing so are beyond
-the scope of this @value{DOCUMENT}. @xref{gawkextlib}, for Internet links to
+the scope of this @value{DOCUMENT}. @DBXREF{gawkextlib} for Internet links to
 the tools.} create a GNU/Linux shared library:
 
 @example
@@ -33460,7 +33671,7 @@ $ @kbd{gcc -fPIC -shared -DHAVE_CONFIG_H -c -O -g -I@var{idir} filefuncs.c}
 $ @kbd{gcc -o filefuncs.so -shared filefuncs.o}
 @end example
 
-Once the library exists, it is loaded by using the @code{@@load} keyword.
+Once the library exists, it is loaded by using the @code{@@load} keyword:
 
 @example
 # file testff.awk
@@ -33524,13 +33735,14 @@ $ @kbd{AWKLIBPATH=$PWD gawk -f testff.awk}
 @end example
 
 @node Extension Samples
-@section The Sample Extensions In The @command{gawk} Distribution
+@section The Sample Extensions in the @command{gawk} Distribution
 @cindex extensions distributed with @command{gawk}
 
-This @value{SECTION} provides brief overviews of the sample extensions
+This @value{SECTION} provides a brief overview of the sample extensions
 that come in the @command{gawk} distribution. Some of them are intended
-for production use, such the @code{filefuncs}, @code{readdir} and @code{inplace} extensions.
-Others mainly provide example code that shows how to use the extension API.
+for production use (e.g., the @code{filefuncs}, @code{readdir}, and
+@code{inplace} extensions).  Others mainly provide example code that
+shows how to use the extension API.
 
 @menu
 * Extension Sample File Functions::   The file functions sample.
@@ -33551,9 +33763,9 @@ Others mainly provide example code that shows how to use the extension API.
 @end menu
 
 @node Extension Sample File Functions
-@subsection File Related Functions
+@subsection File-Related Functions
 
-The @code{filefuncs} extension provides three different functions, as follows:
+The @code{filefuncs} extension provides three different functions, as follows.
 The usage is:
 
 @table @asis
@@ -33564,15 +33776,15 @@ This is how you load the extension.
 @item @code{result = chdir("/some/directory")}
 The @code{chdir()} function is a direct hook to the @code{chdir()}
 system call to change the current directory.  It returns zero
-upon success or less than zero upon error.  In the latter case it updates
-@code{ERRNO}.
+upon success or a value less than zero upon error.
+In the latter case, it updates @code{ERRNO}.
 
 @cindex @code{stat()} extension function
 @item @code{result = stat("/some/path", statdata} [@code{, follow}]@code{)}
 The @code{stat()} function provides a hook into the
 @code{stat()} system call.
-It returns zero upon success or less than zero upon error.
-In the latter case it updates @code{ERRNO}.
+It returns zero upon success or a value less than zero upon error.
+In the latter case, it updates @code{ERRNO}.
 
 By default, it uses the @code{lstat()} system call.  However, if passed
 a third argument, it uses @code{stat()} instead.
@@ -33598,10 +33810,10 @@ array with information retrieved from the filesystem, as follows:
 @item @code{"major"} @tab @code{st_major} @tab Device files
 @item @code{"minor"} @tab @code{st_minor} @tab Device files
 @item @code{"blksize"} @tab @code{st_blksize} @tab All
-@item @code{"pmode"} @tab A human-readable version of the mode value, such as printed by
-@command{ls}.  For example, @code{"-rwxr-xr-x"} @tab All
+@item @code{"pmode"} @tab A human-readable version of the mode value, like that printed by
+@command{ls} (for example, @code{"-rwxr-xr-x"}) @tab All
 @item @code{"linkval"} @tab The value of the symbolic link @tab Symbolic links
-@item @code{"type"} @tab The type of the file as a string. One of
+@item @code{"type"} @tab The type of the file as a string---one of
 @code{"file"},
 @code{"blockdev"},
 @code{"chardev"},
@@ -33611,16 +33823,16 @@ array with information retrieved from the filesystem, as follows:
 @code{"symlink"},
 @code{"door"},
 or
-@code{"unknown"}.
-Not all systems support all file types. @tab All
+@code{"unknown"}
+(not all systems support all file types) @tab All
 @end multitable
 
 @cindex @code{fts()} extension function
 @item @code{flags = or(FTS_PHYSICAL, ...)}
 @itemx @code{result = fts(pathlist, flags, filedata)}
 Walk the file trees provided in @code{pathlist} and fill in the
-@code{filedata} array as described below.  @code{flags} is the bitwise
-OR of several predefined values, also described below.
+@code{filedata} array, as described next.  @code{flags} is the bitwise
+OR of several predefined values, also described in a moment.
 Return zero if there were no errors, otherwise return @minus{}1.
 @end table
 
@@ -33668,17 +33880,18 @@ whether or not @code{FTS_LOGICAL} is set.
 By default, the C library @code{fts()} routines do not return entries for
 @file{.} (dot) and @file{..} (dot-dot).  This option causes entries for
 dot-dot to also be included.  (The extension always includes an entry
-for dot, see below.)
+for dot; more on this in a moment.)
 
 @item FTS_XDEV
 During a traversal, do not cross onto a different mounted filesystem.
 @end table
 
 @item filedata
-The @code{filedata} array is first cleared.  Then, @code{fts()} creates
+The @code{filedata} array holds the results.
+@code{fts()} first clears it.  Then it creates
 an element in @code{filedata} for every element in @code{pathlist}.
 The index is the name of the directory or file given in @code{pathlist}.
-The element for this index is itself an array.  There are two cases.
+The element for this index is itself an array.  There are two cases:
 
 @c nested table
 @table @emph
@@ -33704,8 +33917,8 @@ contain an element named @code{"error"}, which is a string describing the error.
 
 @item The path is a directory
 In this case, the array contains one element for each entry in the
-directory.  If an entry is a file, that element is as for files, just
-described.  If the entry is a directory, that element is (recursively),
+directory.  If an entry is a file, that element is the same as for files, just
+described.  If the entry is a directory, that element is (recursively)
 an array describing the subdirectory.  If @code{FTS_SEEDOT} was provided
 in the flags, then there will also be an element named @code{".."}.  This
 element will be an array containing the data as provided by @code{stat()}.
@@ -33717,15 +33930,15 @@ for a file: @code{"path"}, @code{"stat"}, and @code{"error"}.
 @end table
 
 The @code{fts()} function returns zero if there were no errors.
-Otherwise it returns @minus{}1.
+Otherwise, it returns @minus{}1.
 
 @quotation NOTE
 The @code{fts()} extension does not exactly mimic the
 interface of the C library @code{fts()} routines, choosing instead to
 provide an interface that is based on associative arrays, which is
 more comfortable to use from an @command{awk} program.  This includes the
-lack of a comparison function, since @command{gawk} already provides
-powerful array sorting facilities.  While an @code{fts_read()}-like
+lack of a comparison function, because @command{gawk} already provides
+powerful array sorting facilities.  Although an @code{fts_read()}-like
 interface could have been provided, this felt less natural than simply
 creating a multidimensional array to represent the file hierarchy and
 its information.
@@ -33735,7 +33948,7 @@ See @file{test/fts.awk} in the @command{gawk} distribution for an example
 use of the @code{fts()} extension function.
 
 @node Extension Sample Fnmatch
-@subsection Interface To @code{fnmatch()}
+@subsection Interface to @code{fnmatch()}
 
 This extension provides an interface to the C library
 @code{fnmatch()} function.  The usage is:
@@ -33748,10 +33961,10 @@ This is how you load the extension.
 @item result = fnmatch(pattern, string, flags)
 The return value is zero on success, @code{FNM_NOMATCH}
 if the string did not match the pattern, or
-a different non-zero value if an error occurred.
+a different nonzero value if an error occurred.
 @end table
 
-Besides the @code{fnmatch()} function, the @code{fnmatch} extension
+In addition to the @code{fnmatch()} function, the @code{fnmatch} extension
 adds one constant (@code{FNM_NOMATCH}), and an array of flag values
 named @code{FNM}.
 
@@ -33759,17 +33972,17 @@ The arguments to @code{fnmatch()} are:
 
 @table @code
 @item pattern
-The @value{FN} wildcard to match.
+The @value{FN} wildcard to match
 
 @item string
-The @value{FN} string.
+The @value{FN} string
 
 @item flag
 Either zero, or the bitwise OR of one or more of the
-flags in the @code{FNM} array.
+flags in the @code{FNM} array
 @end table
 
-The flags are follows:
+The flags are as follows:
 
 @multitable @columnfractions .25 .75
 @headitem Array element @tab Corresponding flag defined by @code{fnmatch()}
@@ -33792,9 +34005,9 @@ if (fnmatch("*.a", "foo.c", flags) == FNM_NOMATCH)
 @end example
 
 @node Extension Sample Fork
-@subsection Interface To @code{fork()}, @code{wait()} and @code{waitpid()}
+@subsection Interface to @code{fork()}, @code{wait()}, and @code{waitpid()}
 
-The @code{fork} extension adds three functions, as follows.
+The @code{fork} extension adds three functions, as follows:
 
 @table @code
 @item @@load "fork"
@@ -33803,14 +34016,14 @@ This is how you load the extension.
 @cindex @code{fork()} extension function
 @item pid = fork()
 This function creates a new process. The return value is zero in the
-child and the process-ID number of the child in the parent, or @minus{}1
+child and the process ID number of the child in the parent, or @minus{}1
 upon error. In the latter case, @code{ERRNO} indicates the problem.
 In the child, @code{PROCINFO["pid"]} and @code{PROCINFO["ppid"]} are
 updated to reflect the correct values.
 
 @cindex @code{waitpid()} extension function
 @item ret = waitpid(pid)
-This function takes a numeric argument, which is the process-ID to
+This function takes a numeric argument, which is the process ID to
 wait for. The return value is that of the
 @code{waitpid()} system call.
 
@@ -33838,8 +34051,8 @@ else
 @subsection Enabling In-Place File Editing
 
 @cindex @code{inplace} extension
-The @code{inplace} extension emulates GNU @command{sed}'s @option{-i} option
-which performs ``in place'' editing of each input file.
+The @code{inplace} extension emulates GNU @command{sed}'s @option{-i} option,
+which performs ``in-place'' editing of each input file.
 It uses the bundled @file{inplace.awk} include file to invoke the extension
 properly:
 
@@ -33853,11 +34066,16 @@ properly:
 # Please set INPLACE_SUFFIX to make a backup copy.  For example, you may
 # want to set INPLACE_SUFFIX to .bak on the command line or in a BEGIN rule.
 
+# N.B. We call inplace_end() in the BEGINFILE and END rules so that any
+# actions in an ENDFILE rule will be redirected as expected.
+
 BEGINFILE @{
-    inplace_begin(FILENAME, INPLACE_SUFFIX)
+    if (_inplace_filename != "")
+        inplace_end(_inplace_filename, INPLACE_SUFFIX)
+    inplace_begin(_inplace_filename = FILENAME, INPLACE_SUFFIX)
 @}
 
-ENDFILE @{
+END @{
     inplace_end(FILENAME, INPLACE_SUFFIX)
 @}
 @end group
@@ -33872,6 +34090,10 @@ If @code{INPLACE_SUFFIX} is not an empty string, the original file is
 linked to a backup @value{FN} created by appending that suffix.  Finally,
 the temporary file is renamed to the original @value{FN}.
 
+The @code{_inplace_filename} variable serves to keep track of the
+current filename so as to not invoke @code{inplace_end()} before
+processing the first file.
+
 If any error occurs, the extension issues a fatal error to terminate
 processing immediately without damaging the original file.
 
@@ -33892,7 +34114,7 @@ $ @kbd{gawk -i inplace -v INPLACE_SUFFIX=.bak '@{ gsub(/foo/, "bar") @}}
 @subsection Character and Numeric values: @code{ord()} and @code{chr()}
 
 The @code{ordchr} extension adds two functions, named
-@code{ord()} and @code{chr()}, as follows.
+@code{ord()} and @code{chr()}, as follows:
 
 @table @code
 @item @@load "ordchr"
@@ -33935,14 +34157,14 @@ they are read, with each entry returned as a record.
 The record consists of three fields. The first two are the inode number and the
 @value{FN}, separated by a forward slash character.
 On systems where the directory entry contains the file type, the record
-has a third field (also separated by a slash) which is a single letter
-indicating the type of the file. The letters are file types are shown
-in @ref{table-readdir-file-types}.
+has a third field (also separated by a slash), which is a single letter
+indicating the type of the file. The letters and their corresponding file
+types are shown in @ref{table-readdir-file-types}.
 
 @float Table,table-readdir-file-types
-@caption{File Types Returned By The @code{readdir} Extension}
+@caption{File types returned by the @code{readdir} extension}
 @multitable @columnfractions .1 .9
-@headitem Letter @tab File Type
+@headitem Letter @tab File type
 @item @code{b} @tab Block device
 @item @code{c} @tab Character device
 @item @code{d} @tab Directory
@@ -33970,14 +34192,14 @@ Here is an example:
 @@load "readdir"
 @dots{}
 BEGIN @{ FS = "/" @}
-@{ print "file name is", $2 @}
+@{ print "@value{FN} is", $2 @}
 @end example
 
 @node Extension Sample Revout
 @subsection Reversing Output
 
 The @code{revoutput} extension adds a simple output wrapper that reverses
-the characters in each output line.  It's main purpose is to show how to
+the characters in each output line.  Its main purpose is to show how to
 write an output wrapper, although it may be mildly amusing for the unwary.
 Here is an example:
 
@@ -33991,15 +34213,14 @@ BEGIN @{
 @}
 @end example
 
-The output from this program is:
-@samp{cinap t'nod}.
+The output from this program is @samp{cinap t'nod}.
 
 @node Extension Sample Rev2way
 @subsection Two-Way I/O Example
 
 The @code{revtwoway} extension adds a simple two-way processor that
 reverses the characters in each line sent to it for reading back by
-the @command{awk} program.  It's main purpose is to show how to write
+the @command{awk} program.  Its main purpose is to show how to write
 a two-way processor, although it may also be mildly amusing.
 The following example shows how to use it:
 
@@ -34026,7 +34247,7 @@ is:
 @samp{cinap t'nod}.
 
 @node Extension Sample Read write array
-@subsection Dumping and Restoring An Array
+@subsection Dumping and Restoring an Array
 
 The @code{rwarray} extension adds two functions,
 named @code{writea()} and @code{reada()}, as follows:
@@ -34047,12 +34268,12 @@ success, or zero upon failure.
 @code{reada()} is the inverse of @code{writea()};
 it reads the file named as its first argument, filling in
 the array named as the second argument. It clears the array first.
-Here too, the return value is one on success and zero upon failure.
+Here too, the return value is one on success, or zero upon failure.
 @end table
 
 The array created by @code{reada()} is identical to that written by
 @code{writea()} in the sense that the contents are the same. However,
-due to implementation issues, the array traversal order of the recreated
+due to implementation issues, the array traversal order of the re-created
 array is likely to be different from that of the original array.  As array
 traversal order in @command{awk} is by default undefined, this is (technically)
 not a problem.  If you need to guarantee a particular traversal
@@ -34060,7 +34281,7 @@ order, use the array sorting features in @command{gawk} to do so
 (@pxref{Array Sorting}).
 
 The file contains binary data.  All integral values are written in network
-byte order.  However, double precision floating-point values are written
+byte order.  However, double-precision floating-point values are written
 as native binary data.  Thus, arrays containing only string data can
 theoretically be dumped on systems with one byte order and restored on
 systems with a different one, but this has not been tried.
@@ -34076,7 +34297,7 @@ ret = reada("arraydump.bin", array)
 @end example
 
 @node Extension Sample Readfile
-@subsection Reading An Entire File
+@subsection Reading an Entire File
 
 The @code{readfile} extension adds a single function
 named @code{readfile()}, and an input parser:
@@ -34123,7 +34344,7 @@ This is how you load the extension.
 @cindex @code{gettimeofday()} extension function
 @item the_time = gettimeofday()
 Return the time in seconds that has elapsed since 1970-01-01 UTC as a
-floating point value.  If the time is unavailable on this platform, return
+floating-point value.  If the time is unavailable on this platform, return
 @minus{}1 and set @code{ERRNO}.  The returned time should have sub-second
 precision, but the actual precision may vary based on the platform.
 If the standard C @code{gettimeofday()} system call is available on this
@@ -34135,7 +34356,7 @@ it tries to use @code{GetSystemTimeAsFileTime()}.
 Attempt to sleep for @var{seconds} seconds.  If @var{seconds} is negative,
 or the attempt to sleep fails, return @minus{}1 and set @code{ERRNO}.
 Otherwise, return zero after sleeping for the indicated amount of time.
-Note that @var{seconds} may be a floating-point (non-integral) value.
+Note that @var{seconds} may be a floating-point (nonintegral) value.
 Implementation details: depending on platform availability, this function
 tries to use @code{nanosleep()} or @code{select()} to implement the delay.
 @end table
@@ -34162,26 +34383,35 @@ project provides a number of @command{gawk} extensions, including one for
 processing XML files.  This is the evolution of the original @command{xgawk}
 (XML @command{gawk}) project.
 
-As of this writing, there are five extensions:
+As of this writing, there are seven extensions:
 
 @itemize @value{BULLET}
 @item
-GD graphics library extension.
+@code{errno} extension
 
 @item
-PDF extension.
+GD graphics library extension
 
 @item
-PostgreSQL extension.
+MPFR library extension
+(this provides access to a number of MPFR functions that @command{gawk}'s
+native MPFR support does not)
 
 @item
-MPFR library extension.
-This provides access to a number of MPFR functions which @command{gawk}'s
-native MPFR support does not.
+PDF extension
+
+@item
+PostgreSQL extension
+
+@item
+Redis extension
+
+@item
+Select extension
 
 @item
 XML parser extension, using the @uref{http://expat.sourceforge.net, Expat}
-XML parsing library.
+XML parsing library
 @end itemize
 
 @cindex @command{git} utility
@@ -34227,14 +34457,14 @@ make install                          @ii{Install the extensions}
 
 If you have installed @command{gawk} in the standard way, then you
 will likely not need the @option{--with-gawk} option when configuring
-@code{gawkextlib}.  You may also need to use the @command{sudo} utility
+@code{gawkextlib}.  You may need to use the @command{sudo} utility
 to install both @command{gawk} and @code{gawkextlib}, depending upon
 how your system works.
 
 If you write an extension that you wish to share with other
-@command{gawk} users, please consider doing so through the
+@command{gawk} users, consider doing so through the
 @code{gawkextlib} project.
-See the project's web site for more information.
+See the project's website for more information.
 
 @node Extension summary
 @section Summary
@@ -34242,7 +34472,7 @@ See the project's web site for more information.
 @itemize @value{BULLET}
 @item
 You can write extensions (sometimes called plug-ins) for @command{gawk}
-in C or C++ using the Application Programming Interface (API) defined
+in C or C++ using the application programming interface (API) defined
 by the @command{gawk} developers.
 
 @item
@@ -34252,7 +34482,7 @@ named @code{plugin_is_GPL_compatible}.
 
 @item
 Communication between @command{gawk} and an extension is two-way.
-@command{gawk} passes a @code{struct} to the extension which contains
+@command{gawk} passes a @code{struct} to the extension that contains
 various data fields and function pointers.  The extension can then call
 into @command{gawk} via the supplied function pointers to accomplish
 certain tasks.
@@ -34265,7 +34495,7 @@ By convention, implementation functions are named @code{do_@var{XXXX}()}
 for some @command{awk}-level function @code{@var{XXXX}()}.
 
 @item
-The API is defined in a header file named @file{gawkpi.h}. You must include
+The API is defined in a header file named @file{gawkapi.h}. You must include
 a number of standard header files @emph{before} including it in your source file.
 
 @item
@@ -34273,44 +34503,44 @@ API function pointers are provided for the following kinds of operations:
 
 @itemize @value{BULLET}
 @item
-Allocating, reallocating, and releasing memory.
+Allocating, reallocating, and releasing memory
 
 @item
-Registration functions. You may register
+Registration functions (you may register
 extension functions,
 exit callbacks,
 a version string,
 input parsers,
 output wrappers,
-and two-way processors.
+and two-way processors)
 
 @item
-Printing fatal, warning, and ``lint'' warning messages.
+Printing fatal, warning, and ``lint'' warning messages
 
 @item
-Updating @code{ERRNO}, or unsetting it.
+Updating @code{ERRNO}, or unsetting it
 
 @item
 Accessing parameters, including converting an undefined parameter into
-an array.
+an array
 
 @item
-Symbol table access: retrieving a global variable, creating one,
-or changing one.
+Symbol table access (retrieving a global variable, creating one,
+or changing one)
 
 @item
 Creating and releasing cached values; this provides an
 efficient way to use values for multiple variables and
-can be a big performance win.
+can be a big performance win
 
 @item
-Manipulating arrays:
-retrieving, adding, deleting, and modifying elements;
+Manipulating arrays
+(retrieving, adding, deleting, and modifying elements;
 getting the count of elements in an array;
 creating a new array;
 clearing an array;
 and
-flattening an array for easy C style looping over all its indices and elements.
+flattening an array for easy C-style looping over all its indices and elements)
 @end itemize
 
 @item
@@ -34318,7 +34548,7 @@ The API defines a number of standard data types for representing
 @command{awk} values, array elements, and arrays.
 
 @item
-The API provide convenience functions for constructing values.
+The API provides convenience functions for constructing values.
 It also provides memory management functions to ensure compatibility
 between memory allocated by @command{gawk} and memory allocated by an
 extension.
@@ -34339,13 +34569,13 @@ that loaded it.
 
 @item
 It is easiest to start a new extension by copying the boilerplate code
-described in this @value{CHAPTER}.  Macros in the @file{gawkapi.h} make
-this easier to do.
+described in this @value{CHAPTER}.  Macros in the @file{gawkapi.h} header
+file make this easier to do.
 
 @item
 The @command{gawk} distribution includes a number of small but useful
-sample extensions. The @code{gawkextlib} project includes several more,
-larger, extensions.  If you wish to write an extension and contribute it
+sample extensions. The @code{gawkextlib} project includes several more
+(larger) extensions.  If you wish to write an extension and contribute it
 to the community of @command{gawk} users, the @code{gawkextlib} project
 is the place to do so.
 
@@ -34361,6 +34591,24 @@ Add functions to implement system calls such as @code{chown()},
 @code{chmod()}, and @code{umask()} to the file operations extension
 presented in @ref{Internal File Ops}.
 
+@c Idea from comp.lang.awk, February 2015
+@item
+Write an input parser that prints a prompt if the input is
+a from a ``terminal'' device.  You can use the @code{isatty()}
+function to tell if the input file is a terminal. (Hint: this function
+is usually expensive to call; try to call it just once.)
+The content of the prompt should come from a variable settable
+by @command{awk}-level code.
+You can write the prompt to stanard error. However,
+for best results, open a new file descriptor (or file pointer)
+on @file{/dev/tty} and print the prompt there, in case standard
+error has been redirected.
+
+Why is standard error a better
+choice than standard output for writing the prompt?
+Which reading mechanism should you replace, the one to get
+a record, or the one to read raw bytes?
+
 @item
 (Hard.)
 How would you provide namespaces in @command{gawk}, so that the
@@ -34389,34 +34637,34 @@ and the Glossary:
 @end ifclear
 
 @ifset FOR_PRINT
-Part IV contains two appendices and the license that
+Part IV contains three appendices, the last of which is the license that
 covers the @command{gawk} source code:
 @end ifset
 
 @itemize @value{BULLET}
 @item
-@ref{Language History}.
+@ref{Language History}
 
 @item
-@ref{Installation}.
+@ref{Installation}
 
 @ifclear FOR_PRINT
 @item
-@ref{Notes}.
+@ref{Notes}
 
 @item
-@ref{Basic Concepts}.
+@ref{Basic Concepts}
 
 @item
-@ref{Glossary}.
+@ref{Glossary}
 @end ifclear
 
 @item
-@ref{Copying}.
+@ref{Copying}
 
 @ifclear FOR_PRINT
 @item
-@ref{GNU Free Documentation License}.
+@ref{GNU Free Documentation License}
 @end ifclear
 @end itemize
 @end ifdocbook
@@ -34425,7 +34673,7 @@ covers the @command{gawk} source code:
 @appendix The Evolution of the @command{awk} Language
 
 This @value{DOCUMENT} describes the GNU implementation of @command{awk},
-which follows the POSIX specification.  Many long-time @command{awk}
+which follows the POSIX specification.  Many longtime @command{awk}
 users learned @command{awk} programming with the original @command{awk}
 implementation in Version 7 Unix.  (This implementation was the basis for
 @command{awk} in Berkeley Unix, through 4.3-Reno.  Subsequent versions
@@ -34462,9 +34710,7 @@ online documentation}.
 
 @node V7/SVR3.1
 @appendixsec Major Changes Between V7 and SVR3.1
-@c STARTOFRANGE gawkv
 @cindex @command{awk}, versions of
-@c STARTOFRANGE gawkv1
 @cindex @command{awk}, versions of, changes between V7 and SVR3.1
 
 The @command{awk} language evolved considerably between the release of
@@ -34475,83 +34721,82 @@ cross-references to further details:
 @itemize @value{BULLET}
 @item
 The requirement for @samp{;} to separate rules on a line
-(@pxref{Statements/Lines}).
+(@pxref{Statements/Lines})
 
 @item
 User-defined functions and the @code{return} statement
-(@pxref{User-defined}).
+(@pxref{User-defined})
 
 @item
 The @code{delete} statement (@pxref{Delete}).
 
 @item
 The @code{do}-@code{while} statement
-(@pxref{Do Statement}).
+(@pxref{Do Statement})
 
 @item
 The built-in functions @code{atan2()}, @code{cos()}, @code{sin()}, @code{rand()}, and
-@code{srand()} (@pxref{Numeric Functions}).
+@code{srand()} (@pxref{Numeric Functions})
 
 @item
 The built-in functions @code{gsub()}, @code{sub()}, and @code{match()}
-(@pxref{String Functions}).
+(@pxref{String Functions})
 
 @item
 The built-in functions @code{close()} and @code{system()}
-(@pxref{I/O Functions}).
+(@pxref{I/O Functions})
 
 @item
 The @code{ARGC}, @code{ARGV}, @code{FNR}, @code{RLENGTH}, @code{RSTART},
-and @code{SUBSEP} predefined variables (@pxref{Built-in Variables}).
+and @code{SUBSEP} predefined variables (@pxref{Built-in Variables})
 
 @item
-Assignable @code{$0} (@pxref{Changing Fields}).
+Assignable @code{$0} (@pxref{Changing Fields})
 
 @item
 The conditional expression using the ternary operator @samp{?:}
-(@pxref{Conditional Exp}).
+(@pxref{Conditional Exp})
 
 @item
-The expression @samp{@var{index-variable} in @var{array}} outside of @code{for}
-statements (@pxref{Reference to Elements}).
+The expression @samp{@var{indx} in @var{array}} outside of @code{for}
+statements (@pxref{Reference to Elements})
 
 @item
 The exponentiation operator @samp{^}
 (@pxref{Arithmetic Ops}) and its assignment operator
-form @samp{^=} (@pxref{Assignment Ops}).
+form @samp{^=} (@pxref{Assignment Ops})
 
 @item
 C-compatible operator precedence, which breaks some old @command{awk}
-programs (@pxref{Precedence}).
+programs (@pxref{Precedence})
 
 @item
 Regexps as the value of @code{FS}
 (@pxref{Field Separators}) and as the
 third argument to the @code{split()} function
 (@pxref{String Functions}), rather than using only the first character
-of @code{FS}.
+of @code{FS}
 
 @item
 Dynamic regexps as operands of the @samp{~} and @samp{!~} operators
-(@pxref{Computed Regexps}).
+(@pxref{Computed Regexps})
 
 @item
 The escape sequences @samp{\b}, @samp{\f}, and @samp{\r}
-(@pxref{Escape Sequences}).
+(@pxref{Escape Sequences})
 
 @item
 Redirection of input for the @code{getline} function
-(@pxref{Getline}).
+(@pxref{Getline})
 
 @item
 Multiple @code{BEGIN} and @code{END} rules
-(@pxref{BEGIN/END}).
+(@pxref{BEGIN/END})
 
 @item
 Multidimensional arrays
-(@pxref{Multidimensional}).
+(@pxref{Multidimensional})
 @end itemize
-@c ENDOFRANGE gawkv1
 
 @node SVR4
 @appendixsec Changes Between SVR3.1 and SVR4
@@ -34562,54 +34807,54 @@ The System V Release 4 (1989) version of Unix @command{awk} added these features
 
 @itemize @value{BULLET}
 @item
-The @code{ENVIRON} array (@pxref{Built-in Variables}).
+The @code{ENVIRON} array (@pxref{Built-in Variables})
 @c gawk and MKS awk
 
 @item
 Multiple @option{-f} options on the command line
-(@pxref{Options}).
+(@pxref{Options})
 @c MKS awk
 
 @item
 The @option{-v} option for assigning variables before program execution begins
-(@pxref{Options}).
+(@pxref{Options})
 @c GNU, Bell Laboratories & MKS together
 
 @item
-The @option{--} signal for terminating command-line options.
+The @option{--} signal for terminating command-line options
 
 @item
 The @samp{\a}, @samp{\v}, and @samp{\x} escape sequences
-(@pxref{Escape Sequences}).
+(@pxref{Escape Sequences})
 @c GNU, for ANSI C compat
 
 @item
 A defined return value for the @code{srand()} built-in function
-(@pxref{Numeric Functions}).
+(@pxref{Numeric Functions})
 
 @item
 The @code{toupper()} and @code{tolower()} built-in string functions
 for case translation
-(@pxref{String Functions}).
+(@pxref{String Functions})
 
 @item
-A cleaner specification for the @code{%c} format-control letter in the
+A cleaner specification for the @samp{%c} format-control letter in the
 @code{printf} function
-(@pxref{Control Letters}).
+(@pxref{Control Letters})
 
 @item
 The ability to dynamically pass the field width and precision (@code{"%*.*d"})
 in the argument list of @code{printf} and @code{sprintf()}
-(@pxref{Control Letters}).
+(@pxref{Control Letters})
 
 @item
 The use of regexp constants, such as @code{/foo/}, as expressions, where
 they are equivalent to using the matching operator, as in @samp{$0 ~ /foo/}
-(@pxref{Using Constant Regexps}).
+(@pxref{Using Constant Regexps})
 
 @item
 Processing of escape sequences inside command-line variable assignments
-(@pxref{Assignment Options}).
+(@pxref{Assignment Options})
 @end itemize
 
 @node POSIX
@@ -34623,23 +34868,23 @@ introduced the following changes into the language:
 @itemize @value{BULLET}
 @item
 The use of @option{-W} for implementation-specific options
-(@pxref{Options}).
+(@pxref{Options})
 
 @item
 The use of @code{CONVFMT} for controlling the conversion of numbers
-to strings (@pxref{Conversion}).
+to strings (@pxref{Conversion})
 
 @item
 The concept of a numeric string and tighter comparison rules to go
-with it (@pxref{Typing and Comparison}).
+with it (@pxref{Typing and Comparison})
 
 @item
 The use of predefined variables as function parameter names is forbidden
-(@pxref{Definition Syntax}).
+(@pxref{Definition Syntax})
 
 @item
 More complete documentation of many of the previously undocumented
-features of the language.
+features of the language
 @end itemize
 
 In 2012, a number of extensions that had been commonly available for
@@ -34648,25 +34893,24 @@ many years were finally added to POSIX. They are:
 @itemize @value{BULLET}
 @item
 The @code{fflush()} built-in function for flushing buffered output
-(@pxref{I/O Functions}).
+(@pxref{I/O Functions})
 
 @item
 The @code{nextfile} statement
-(@pxref{Nextfile Statement}).
+(@pxref{Nextfile Statement})
 
 @item
 The ability to delete all of an array at once with @samp{delete @var{array}}
-(@pxref{Delete}).
+(@pxref{Delete})
 
 @end itemize
 
-@xref{Common Extensions}, for a list of common extensions
+@DBXREF{Common Extensions} for a list of common extensions
 not permitted by the POSIX standard.
 
 The 2008 POSIX standard can be found online at
 @url{http://www.opengroup.org/onlinepubs/9699919799/}.
 
-@c ENDOFRANGE gawkv
 
 @node BTL
 @appendixsec Extensions in Brian Kernighan's @command{awk}
@@ -34680,43 +34924,40 @@ has made his version available via his home page
 (@pxref{Other Versions}).
 
 This @value{SECTION} describes common extensions that
-originally appeared in his version of @command{awk}.
+originally appeared in his version of @command{awk}:
 
 @itemize @value{BULLET}
 @item
 The @samp{**} and @samp{**=} operators
 (@pxref{Arithmetic Ops}
 and
-@ref{Assignment Ops}).
+@ref{Assignment Ops})
 
 @item
 The use of @code{func} as an abbreviation for @code{function}
-(@pxref{Definition Syntax}).
+(@pxref{Definition Syntax})
 
 @item
 The @code{fflush()} built-in function for flushing buffered output
-(@pxref{I/O Functions}).
+(@pxref{I/O Functions})
 
 @ignore
 @item
 The @code{SYMTAB} array, that allows access to @command{awk}'s internal symbol
 table. This feature was never documented for his @command{awk}, largely because
 it is somewhat shakily implemented. For instance, you cannot access arrays
-or array elements through it.
+or array elements through it
 @end ignore
 @end itemize
 
-@xref{Common Extensions}, for a full list of the extensions
+@DBXREF{Common Extensions} for a full list of the extensions
 available in his @command{awk}.
 
 @node POSIX/GNU
 @appendixsec Extensions in @command{gawk} Not in POSIX @command{awk}
 
-@c STARTOFRANGE fripls
 @cindex compatibility mode (@command{gawk}), extensions
-@c STARTOFRANGE exgnot
 @cindex extensions, in @command{gawk}, not in POSIX @command{awk}
-@c STARTOFRANGE posnot
 @cindex POSIX, @command{gawk} extensions not included in
 The GNU implementation, @command{gawk}, adds a large number of features.
 They can all be disabled with either the @option{--traditional} or
@@ -34735,7 +34976,7 @@ Additional predefined variables:
 @itemize @value{MINUS}
 @item
 The
-@code{ARGIND}
+@code{ARGIND},
 @code{BINMODE},
 @code{ERRNO},
 @code{FIELDWIDTHS},
@@ -34747,7 +34988,7 @@ The
 and
 @code{TEXTDOMAIN}
 variables
-(@pxref{Built-in Variables}).
+(@pxref{Built-in Variables})
 @end itemize
 
 @item
@@ -34755,15 +34996,15 @@ Special files in I/O redirections:
 
 @itemize @value{MINUS}
 @item
-The @file{/dev/stdin}, @file{/dev/stdout}, @file{/dev/stderr} and
+The @file{/dev/stdin}, @file{/dev/stdout}, @file{/dev/stderr}, and
 @file{/dev/fd/@var{N}} special @value{FN}s
-(@pxref{Special Files}).
+(@pxref{Special Files})
 
 @item
 The @file{/inet}, @file{/inet4}, and @samp{/inet6} special files for
 TCP/IP networking using @samp{|&} to specify which version of the
-IP protocol to use.
-(@pxref{TCP/IP Networking}).
+IP protocol to use
+(@pxref{TCP/IP Networking})
 @end itemize
 
 @item
@@ -34772,37 +35013,41 @@ Changes and/or additions to the language:
 @itemize @value{MINUS}
 @item
 The @samp{\x} escape sequence
-(@pxref{Escape Sequences}).
+(@pxref{Escape Sequences})
 
 @item
 Full support for both POSIX and GNU regexps
-(@pxref{Regexp}).
+(@pxref{Regexp})
 
 @item
 The ability for @code{FS} and for the third
 argument to @code{split()} to be null strings
-(@pxref{Single Character Fields}).
+(@pxref{Single Character Fields})
 
 @item
 The ability for @code{RS} to be a regexp
-(@pxref{Records}).
+(@pxref{Records})
 
 @item
 The ability to use octal and hexadecimal constants in @command{awk}
 program source code
-(@pxref{Nondecimal-numbers}).
+(@pxref{Nondecimal-numbers})
 
 @item
 The @samp{|&} operator for two-way I/O to a coprocess
-(@pxref{Two-way I/O}).
+(@pxref{Two-way I/O})
 
 @item
 Indirect function calls
-(@pxref{Indirect Calls}).
+(@pxref{Indirect Calls})
 
 @item
 Directories on the command line produce a warning and are skipped
-(@pxref{Command-line directories}).
+(@pxref{Command-line directories})
+
+@item
+Output with @code{print} and @code{printf} need not be fatal
+(@pxref{Nonfatal})
 @end itemize
 
 @item
@@ -34810,12 +35055,12 @@ New keywords:
 
 @itemize @value{MINUS}
 @item
-The @code{BEGINFILE} and @code{ENDFILE} special patterns.
-(@pxref{BEGINFILE/ENDFILE}).
+The @code{BEGINFILE} and @code{ENDFILE} special patterns
+(@pxref{BEGINFILE/ENDFILE})
 
 @item
 The @code{switch} statement
-(@pxref{Switch Statement}).
+(@pxref{Switch Statement})
 @end itemize
 
 @item
@@ -34825,30 +35070,30 @@ Changes to standard @command{awk} functions:
 @item
 The optional second argument to @code{close()} that allows closing one end
 of a two-way pipe to a coprocess
-(@pxref{Two-way I/O}).
+(@pxref{Two-way I/O})
 
 @item
-POSIX compliance for @code{gsub()} and @code{sub()} with @option{--posix}.
+POSIX compliance for @code{gsub()} and @code{sub()} with @option{--posix}
 
 @item
 The @code{length()} function accepts an array argument
 and returns the number of elements in the array
-(@pxref{String Functions}).
+(@pxref{String Functions})
 
 @item
 The optional third argument to the @code{match()} function
 for capturing text-matching subexpressions within a regexp
-(@pxref{String Functions}).
+(@pxref{String Functions})
 
 @item
 Positional specifiers in @code{printf} formats for
 making translations easier
-(@pxref{Printf Ordering}).
+(@pxref{Printf Ordering})
 
 @item
 The @code{split()} function's additional optional fourth
-argument which is an array to hold the text of the field separators.
-(@pxref{String Functions}).
+argument, which is an array to hold the text of the field separators
+(@pxref{String Functions})
 @end itemize
 
 @item
@@ -34858,16 +35103,16 @@ Additional functions only in @command{gawk}:
 @item
 The @code{gensub()}, @code{patsplit()}, and @code{strtonum()} functions
 for more powerful text manipulation
-(@pxref{String Functions}).
+(@pxref{String Functions})
 
 @item
 The @code{asort()} and @code{asorti()} functions for sorting arrays
-(@pxref{Array Sorting}).
+(@pxref{Array Sorting})
 
 @item
 The @code{mktime()}, @code{systime()}, and @code{strftime()}
 functions for working with timestamps
-(@pxref{Time Functions}).
+(@pxref{Time Functions})
 
 @item
 The
@@ -34879,17 +35124,22 @@ The
 and
 @code{xor()}
 functions for bit manipulation
-(@pxref{Bitwise Functions}).
+(@pxref{Bitwise Functions})
 @c In 4.1, and(), or() and xor() grew the ability to take > 2 arguments
 
 @item
 The @code{isarray()} function to check if a variable is an array or not
-(@pxref{Type Functions}).
+(@pxref{Type Functions})
 
 @item
-The @code{bindtextdomain()}, @code{dcgettext()} and @code{dcngettext()}
+The @code{bindtextdomain()}, @code{dcgettext()}, and @code{dcngettext()}
 functions for internationalization
-(@pxref{Programmer i18n}).
+(@pxref{Programmer i18n})
+
+@item
+The @code{intdiv()} function for doing integer
+division and remainder
+(@pxref{Numeric Functions})
 @end itemize
 
 @item
@@ -34899,12 +35149,12 @@ Changes and/or additions in the command-line options:
 @item
 The @env{AWKPATH} environment variable for specifying a path search for
 the @option{-f} command-line option
-(@pxref{Options}).
+(@pxref{Options})
 
 @item
 The @env{AWKLIBPATH} environment variable for specifying a path search for
 the @option{-l} command-line option
-(@pxref{Options}).
+(@pxref{Options})
 
 @item
 The
@@ -34933,7 +35183,7 @@ The
 and
 @option{-V}
 short options. Also, the
-ability to use GNU-style long-named options that start with @option{--}
+ability to use GNU-style long-named options that start with @option{--},
 and the
 @option{--assign},
 @option{--bignum},
@@ -35013,7 +35263,7 @@ GCC for VAX and Alpha has not been tested for a while.
 @end itemize
 
 @item
-Support for the following obsolete systems was removed from the code
+Support for the following obsolete system was removed from the code
 for @command{gawk} @value{PVERSION} 4.1:
 
 @c nested table
@@ -35023,16 +35273,19 @@ Ultrix
 @end itemize
 
 @item
-@c FIXME: Verify the version here.
-Support for MirBSD was removed at @command{gawk} @value{PVERSION} 4.2.
+Support for the following systems was removed from the code
+for @command{gawk} @value{PVERSION} 4.2:
+
+@c nested table
+@itemize @value{MINUS}
+@item
+MirBSD
+@end itemize
 
 @end itemize
 
 @c XXX ADD MORE STUFF HERE
 
-@c ENDOFRANGE fripls
-@c ENDOFRANGE exgnot
-@c ENDOFRANGE posnot
 
 @c This does not need to be in the formal book.
 @ifclear FOR_PRINT
@@ -35614,11 +35867,11 @@ load @command{awk} library files.
 @item
 The @option{-l} and @option{--load} options load compiled dynamic extensions.
 
-@item 
+@item
 The @option{-M} and @option{--bignum} options enable MPFR.
 
 @item
-The @option{-o} only does pretty-printing.
+The @option{-o} option only does pretty-printing.
 
 @item
 The @option{-p} option is used for profiling.
@@ -35641,6 +35894,44 @@ with a minimum of two
 The dynamic extension interface was completely redone
 (@pxref{Dynamic Extensions}).
 
+@item
+Support for Ultrix was removed.
+
+@end itemize
+
+Version 4.2 introduced the following changes:
+
+@itemize @bullet
+@item
+Changes to @code{ENVIRON} are reflected into @command{gawk}'s
+environment and that of programs that it runs.
+@xref{Auto-set}.
+
+@item
+The @option{--pretty-print} option no longer runs the @command{awk}
+program too.
+@xref{Options}.
+
+@item
+The @command{igawk} program and its manual page are no longer
+installed when @command{gawk} is built.
+@xref{Igawk Program}.
+
+@item
+The @code{intdiv()} function.
+@xref{Numeric Functions}.
+
+@item
+The maximum number of hexdecimal digits in @samp{\x} escapes
+is now two.
+@xref{Escape Sequences}.
+
+@item
+Nonfatal output with @code{print} and @code{printf}.
+@xref{Nonfatal}.
+
+@item
+Support for MirBSD was removed.
 @end itemize
 
 @c XXX ADD MORE STUFF HERE
@@ -35653,12 +35944,12 @@ The dynamic extension interface was completely redone
 @cindex extensions, @command{mawk}
 The following table summarizes the common extensions supported
 by @command{gawk}, Brian Kernighan's @command{awk}, and @command{mawk},
-the three most widely-used freely available versions of @command{awk}
+the three most widely used freely available versions of @command{awk}
 (@pxref{Other Versions}).
 
-@multitable {@file{/dev/stderr} special file} {BWK Awk} {Mawk} {GNU Awk} {Now standard}
-@headitem Feature @tab BWK Awk @tab Mawk @tab GNU Awk @tab Now standard
-@item @samp{\x} Escape sequence @tab X @tab X @tab X @tab
+@multitable {@file{/dev/stderr} special file} {BWK @command{awk}} {@command{mawk}} {@command{gawk}} {Now standard}
+@headitem Feature @tab BWK @command{awk} @tab @command{mawk} @tab @command{gawk} @tab Now standard
+@item @samp{\x} escape sequence @tab X @tab X @tab X @tab
 @item @code{FS} as null string @tab X @tab X @tab X @tab
 @item @file{/dev/stdin} special file @tab X @tab X @tab X @tab
 @item @file{/dev/stdout} special file @tab X @tab X @tab X @tab
@@ -35671,7 +35962,7 @@ the three most widely-used freely available versions of @command{awk}
 @item @code{func} keyword @tab X @tab @tab X @tab
 @item @code{BINMODE} variable @tab @tab X @tab X @tab
 @item @code{RS} as regexp @tab @tab X @tab X @tab
-@item Time related functions @tab @tab X @tab X @tab
+@item Time-related functions @tab @tab X @tab X @tab
 @end multitable
 
 @node Ranges and Locales
@@ -35687,9 +35978,9 @@ the first character in the range and the last character in the range,
 inclusive.  Ordering was based on the numeric value of each character
 in the machine's native character set.  Thus, on ASCII-based systems,
 @samp{[a-z]} matched all the lowercase letters, and only the lowercase
-letters, since the numeric values for the letters from @samp{a} through
+letters, as the numeric values for the letters from @samp{a} through
 @samp{z} were contiguous.  (On an EBCDIC system, the range @samp{[a-z]}
-includes additional, non-alphabetic characters as well.)
+includes additional nonalphabetic characters as well.)
 
 Almost all introductory Unix literature explained range expressions
 as working in this fashion, and in particular, would teach that the
@@ -35698,8 +35989,8 @@ that @samp{[A-Z]} was the ``correct'' way to match uppercase letters.
 And indeed, this was true.@footnote{And Life was good.}
 
 The 1992 POSIX standard introduced the idea of locales (@pxref{Locales}).
-Since many locales include other letters besides the plain twenty-six
-letters of the American English alphabet, the POSIX standard added
+Because many locales include other letters besides the plain 26
+letters of the English alphabet, the POSIX standard added
 character classes (@pxref{Bracket Expressions}) as a way to match
 different kinds of characters besides the traditional ones in the ASCII
 character set.
@@ -35714,9 +36005,9 @@ What does that mean?
 In many locales, @samp{A} and @samp{a} are both less than @samp{B}.
 In other words, these locales sort characters in dictionary order,
 and @samp{[a-dx-z]} is typically not equivalent to @samp{[abcdxyz]};
-instead it might be equivalent to @samp{[ABCXYabcdxyz]}, for example.
+instead, it might be equivalent to @samp{[ABCXYabcdxyz]}, for example.
 
-This point needs to be emphasized: Much literature teaches that you should
+This point needs to be emphasized: much literature teaches that you should
 use @samp{[a-z]} to match a lowercase character.  But on systems with
 non-ASCII locales, this also matches all of the uppercase characters
 except @samp{A} or @samp{Z}!  This was a continuous cause of confusion, even well
@@ -35732,7 +36023,7 @@ $ @kbd{echo something1234abc | gawk-3.1.8 '@{ sub("[A-Z]*$", ""); print @}'}
 @end example
 
 @noindent
-This output is unexpected, since the @samp{bc} at the end of
+This output is unexpected, as the @samp{bc} at the end of
 @samp{something1234abc} should not normally match @samp{[A-Z]*}.
 This result is due to the locale setting (and thus you may not see
 it on your system).
@@ -35743,13 +36034,13 @@ is perfectly valid in ASCII, but is not valid in many Unicode locales,
 such as @code{en_US.UTF-8}.
 
 Early versions of @command{gawk} used regexp matching code that was not
-locale aware, so ranges had their traditional interpretation.
+locale-aware, so ranges had their traditional interpretation.
 
 When @command{gawk} switched to using locale-aware regexp matchers,
 the problems began; especially as both GNU/Linux and commercial Unix
 vendors started implementing non-ASCII locales, @emph{and making them
 the default}.  Perhaps the most frequently asked question became something
-like ``why does @samp{[A-Z]} match lowercase letters?!?''
+like, ``Why does @samp{[A-Z]} match lowercase letters?!?''
 
 @cindex Berry, Karl
 This situation existed for close to 10 years, if not more, and
@@ -35759,7 +36050,7 @@ was in the user's locale.  During the development of @value{PVERSION} 4.0,
 he modified @command{gawk} to always treat ranges in the original,
 pre-POSIX fashion, unless @option{--posix} was used (@pxref{Options}).@footnote{And
 thus was born the Campaign for Rational Range Interpretation (or
-RRI). A number of GNU tools have either implemented this change,
+RRI). A number of GNU tools have already implemented this change,
 or will soon.  Thanks to Karl Berry for coining the phrase ``Rational
 Range Interpretation.''}
 
@@ -35773,9 +36064,10 @@ and
 
 By using this lovely technical term, the standard gives license
 to implementors to implement ranges in whatever way they choose.
-The @command{gawk} maintainer chose to apply the pre-POSIX meaning in all
-cases: the default regexp matching; with @option{--traditional} and with
-@option{--posix}; in all cases, @command{gawk} remains POSIX compliant.
+The @command{gawk} maintainer chose to apply the pre-POSIX meaning
+both with the default regexp matching and when @option{--traditional} or
+@option{--posix} are used.
+In all cases @command{gawk} remains POSIX-compliant.
 
 @node Contributors
 @appendixsec Major Contributors to @command{gawk}
@@ -35821,7 +36113,7 @@ to around 90 pages.
 Richard Stallman
 helped finish the implementation and the initial draft of this
 @value{DOCUMENT}.
-He is also the founder of the FSF and the GNU project.
+He is also the founder of the FSF and the GNU Project.
 
 @item
 @cindex Woods, John
@@ -35967,7 +36259,7 @@ Michael Benzinger contributed the initial code for @code{switch} statements.
 @cindex McPhee, Patrick
 Patrick T.J.@: McPhee contributed the code for dynamic loading in Windows32
 environments.
-(This is no longer supported)
+(This is no longer supported.)
 
 @item
 @cindex Wallin, Anders
@@ -35985,28 +36277,28 @@ John Haque made the following contributions:
 @itemize @value{MINUS}
 @item
 The modifications to convert @command{gawk}
-into a byte-code interpreter, including the debugger.
+into a byte-code interpreter, including the debugger
 
 @item
-The addition of true arrays of arrays.
+The addition of true arrays of arrays
 
 @item
-The additional modifications for support of arbitrary precision arithmetic.
+The additional modifications for support of arbitrary-precision arithmetic
 
 @item
 The initial text of
-@ref{Arbitrary Precision Arithmetic}.
+@ref{Arbitrary Precision Arithmetic}
 
 @item
 The work to merge the three versions of @command{gawk}
-into one, for the 4.1 release.
+into one, for the 4.1 release
 
 @item
-Improved array internals for arrays indexed by integers.
+Improved array internals for arrays indexed by integers
 
 @item
-The improved array sorting features were driven by John together
-with Pat Rankin.
+The improved array sorting features were also driven by John, together
+with Pat Rankin
 @end itemize
 
 @cindex Papadopoulos, Panos
@@ -36047,10 +36339,10 @@ helping David Trueman, and as the primary maintainer since around 1994.
 @itemize @value{BULLET}
 @item
 The @command{awk} language has evolved over time. The first release
-was with V7 Unix circa 1978.  In 1987 for System V Release 3.1,
+was with V7 Unix, circa 1978.  In 1987, for System V Release 3.1,
 major additions, including user-defined functions, were made to the language.
 Additional changes were made for System V Release 4, in 1989.
-Since then, further minor changes happen under the auspices of the
+Since then, further minor changes have happened under the auspices of the
 POSIX standard.
 
 @item
@@ -36066,7 +36358,7 @@ options.
 The interaction of POSIX locales and regexp matching in @command{gawk} has been confusing over
 the years. Today, @command{gawk} implements Rational Range Interpretation, where
 ranges of the form @samp{[a-z]} match @emph{only} the characters numerically between
-@samp{a} through @samp{z} in the machine's native character set.  Usually this is ASCII
+@samp{a} through @samp{z} in the machine's native character set.  Usually this is ASCII,
 but it can be EBCDIC on IBM S/390 systems.
 
 @item
@@ -36081,16 +36373,14 @@ the appropriate credit where credit is due.
 
 @c last two commas are part of see also
 @cindex operating systems, See Also GNU/Linux@comma{} PC operating systems@comma{} Unix
-@c STARTOFRANGE gligawk
 @cindex @command{gawk}, installing
-@c STARTOFRANGE ingawk
 @cindex installing @command{gawk}
 This appendix provides instructions for installing @command{gawk} on the
 various platforms that are supported by the developers.  The primary
 developer supports GNU/Linux (and Unix), whereas the other ports are
 contributed.
-@xref{Bugs},
-for the electronic mail addresses of the people who maintain
+@DBXREF{Bugs}
+for the email addresses of the people who maintain
 the respective ports.
 
 @menu
@@ -36144,7 +36434,7 @@ wget http://ftp.gnu.org/gnu/gawk/gawk-@value{VERSION}.@value{PATCHLEVEL}.tar.gz
 
 The GNU software archive is mirrored around the world.
 The up-to-date list of mirror sites is available from
-@uref{http://www.gnu.org/order/ftp.html, the main FSF web site}.
+@uref{http://www.gnu.org/order/ftp.html, the main FSF website}.
 Try to use one of the mirrors; they
 will be less busy, and you can usually find one closer to your site.
 
@@ -36153,9 +36443,9 @@ will be less busy, and you can usually find one closer to your site.
 @command{gawk} is distributed as several @code{tar} files compressed with
 different compression programs: @command{gzip}, @command{bzip2},
 and @command{xz}. For simplicity, the rest of these instructions assume
-you are using the one compressed with the GNU Zip program, @code{gzip}.
+you are using the one compressed with the GNU Gzip program (@command{gzip}).
 
-Once you have the distribution (for example,
+Once you have the distribution (e.g.,
 @file{gawk-@value{VERSION}.@value{PATCHLEVEL}.tar.gz}),
 use @code{gzip} to expand the
 file and then use @code{tar} to extract it.  You can use the following
@@ -36193,7 +36483,6 @@ a local expert.
 
 @node Distribution contents
 @appendixsubsec Contents of the @command{gawk} Distribution
-@c STARTOFRANGE gawdis
 @cindex @command{gawk}, distribution
 
 The @command{gawk} distribution has a number of C source files,
@@ -36205,12 +36494,12 @@ operating systems:
 
 @table @asis
 @item Various @samp{.c}, @samp{.y}, and @samp{.h} files
-The actual @command{gawk} source code.
+These files contain the actual @command{gawk} source code.
 @end table
 
 @table @file
 @item ABOUT-NLS
-Information about GNU @command{gettext} and translations.
+A file containing information about GNU @command{gettext} and translations.
 
 @item AUTHORS
 A file with some information about the authorship of @command{gawk}.
@@ -36240,7 +36529,7 @@ An older list of changes to @command{gawk}.
 The GNU General Public License.
 
 @item POSIX.STD
-A description of behaviors in the POSIX standard for @command{awk} which
+A description of behaviors in the POSIX standard for @command{awk} that
 are left undefined, or where @command{gawk} may not comply fully, as well
 as a list of things that the POSIX standard should describe but does not.
 
@@ -36248,7 +36537,7 @@ as a list of things that the POSIX standard should describe but does not.
 @item doc/awkforai.txt
 Pointers to the original draft of
 a short article describing why @command{gawk} is a good language for
-Artificial Intelligence (AI) programming.
+artificial intelligence (AI) programming.
 
 @item doc/bc_notes
 A brief description of @command{gawk}'s ``byte code'' internals.
@@ -36291,10 +36580,10 @@ The generated Info file for this @value{DOCUMENT}.
 @item doc/gawkinet.texi
 The Texinfo source file for
 @ifinfo
-@inforef{Top, , General Introduction, gawkinet, TCP/IP Internetworking with @command{gawk}}.
+@inforef{Top, , General Introduction, gawkinet, @value{GAWKINETTITLE}}.
 @end ifinfo
 @ifnotinfo
-@cite{TCP/IP Internetworking with @command{gawk}}.
+@cite{@value{GAWKINETTITLE}}.
 @end ifnotinfo
 It should be processed with @TeX{}
 (via @command{texi2dvi} or @command{texi2pdf})
@@ -36303,7 +36592,7 @@ with @command{makeinfo} to produce an Info or HTML file.
 
 @item doc/gawkinet.info
 The generated Info file for
-@cite{TCP/IP Internetworking with @command{gawk}}.
+@cite{@value{GAWKINETTITLE}}.
 
 @item doc/igawk.1
 The @command{troff} source for a manual page describing the @command{igawk}
@@ -36365,6 +36654,12 @@ The source code, manual pages, and infrastructure files for
 the sample extensions included with @command{gawk}.
 @xref{Dynamic Extensions}, for more information.
 
+@item extras/*
+Additional non-essential files.  Currently, this directory contains some shell
+startup files to be installed in @file{/etc/profile.d} to aid in manipulating
+the @env{AWKPATH} and @env{AWKLIBPATH} environment variables.
+@xref{Shell Startup Files}, for more information.
+
 @item posix/*
 Files needed for building @command{gawk} on POSIX-compliant systems.
 
@@ -36373,11 +36668,11 @@ Files needed for building @command{gawk} under MS-Windows
 @ifclear FOR_PRINT
 and OS/2
 @end ifclear
-(@pxref{PC Installation}, for details).
+(@DBPXREF{PC Installation} for details).
 
 @item vms/*
 Files needed for building @command{gawk} under Vax/VMS and OpenVMS
-(@pxref{VMS Installation}, for details).
+(@DBPXREF{VMS Installation} for details).
 
 @item test/*
 A test suite for
@@ -36386,10 +36681,9 @@ directory to run your version of @command{gawk} against the test suite.
 If @command{gawk} successfully passes @samp{make check}, then you can
 be confident of a successful port.
 @end table
-@c ENDOFRANGE gawdis
 
 @node Unix Installation
-@appendixsec Compiling and Installing @command{gawk} on Unix-like Systems
+@appendixsec Compiling and Installing @command{gawk} on Unix-Like Systems
 
 Usually, you can compile and install @command{gawk} by typing only two
 commands.  However, if you use an unusual system, you may need
@@ -36397,12 +36691,13 @@ to configure @command{gawk} for your system yourself.
 
 @menu
 * Quick Installation::               Compiling @command{gawk} under Unix.
+* Shell Startup Files::              Shell convenience functions.
 * Additional Configuration Options:: Other compile-time options.
 * Configuration Philosophy::         How it's all supposed to work.
 @end menu
 
 @node Quick Installation
-@appendixsubsec Compiling @command{gawk} for Unix-like Systems
+@appendixsubsec Compiling @command{gawk} for Unix-Like Systems
 
 The normal installation steps should work on all modern commercial
 Unix-derived systems, GNU/Linux, BSD-based systems, and the Cygwin
@@ -36419,7 +36714,7 @@ described fully in
 @cite{Autoconf---Generating Automatic Configuration Scripts},
 which can be found online at
 @uref{http://www.gnu.org/software/autoconf/manual/index.html,
-the Free Software Foundation's web site}.)
+the Free Software Foundation's website}.)
 @end ifnotinfo
 @ifinfo
 (The Autoconf software is described fully starting with
@@ -36466,7 +36761,7 @@ run @samp{make check}.  All of the tests should succeed.
 If these steps do not work, or if any of the tests fail,
 check the files in the @file{README_d} directory to see if you've
 found a known problem.  If the failure is not described there,
-please send in a bug report (@pxref{Bugs}).
+send in a bug report (@pxref{Bugs}).
 
 Of course, once you've built @command{gawk}, it is likely that you will
 wish to install it.  To do so, you need to run the command @samp{make
@@ -36477,6 +36772,44 @@ is likely that you will be asked for your password, and you will have
 to have been set up previously as a user who is allowed to run the
 @command{sudo} command.
 
+@node Shell Startup Files
+@appendixsubsec Shell Startup Files
+
+The distribution contains shell startup files @file{gawk.sh} and
+@file{gawk.csh} containing functions to aid in manipulating
+the @env{AWKPATH} and @env{AWKLIBPATH} environment variables.
+On a Fedora system, these files should be installed in @file{/etc/profile.d};
+on other platforms, the appropriate location may be different.
+
+@table @command
+
+@cindex @command{gawkpath_default} shell function
+@item gawkpath_default
+Reset the @env{AWKPATH} environment variable to its default value.
+
+@cindex @command{gawkpath_prepend} shell function
+@item gawkpath_prepend
+Add the argument to the front of the @env{AWKPATH} environment variable.
+
+@cindex @command{gawkpath_append} shell function
+@item gawkpath_append
+Add the argument to the end of the @env{AWKPATH} environment variable.
+
+@cindex @command{gawklibpath_default} shell function
+@item gawklibpath_default
+Reset the @env{AWKLIBPATH} environment variable to its default value.
+
+@cindex @command{gawklibpath_prepend} shell function
+@item gawklibpath_prepend
+Add the argument to the front of the @env{AWKLIBPATH} environment variable.
+
+@cindex @command{gawklibpath_append} shell function
+@item gawklibpath_append
+Add the argument to the end of the @env{AWKLIBPATH} environment variable.
+
+@end table
+
+
 @node Additional Configuration Options
 @appendixsubsec Additional Configuration Options
 @cindex @command{gawk}, configuring, options
@@ -36498,7 +36831,7 @@ can be configured and compiled.
 @cindex @option{--disable-lint} configuration option
 @cindex configuration option, @code{--disable-lint}
 @item --disable-lint
-Disable all lint checking within @code{gawk}.  The
+Disable all lint checking within @command{gawk}.  The
 @option{--lint} and @option{--lint-old} options
 (@pxref{Options})
 are accepted, but silently do nothing.
@@ -36506,14 +36839,17 @@ Similarly, setting the @code{LINT} variable
 (@pxref{User-modified})
 has no effect on the running @command{awk} program.
 
-When used with GCC's automatic dead-code-elimination, this option
+When used with the GNU Compiler Collection's (GCC's)
+automatic dead-code-elimination, this option
 cuts almost 23K bytes off the size of the @command{gawk}
 executable on GNU/Linux x86_64 systems.  Results on other systems and
 with other compilers are likely to vary.
 Using this option may bring you some slight performance improvement.
 
+@quotation CAUTION
 Using this option will cause some of the tests in the test suite
 to fail.  This option may be removed at a later date.
+@end quotation
 
 @cindex @option{--disable-nls} configuration option
 @cindex configuration option, @code{--disable-nls}
@@ -36530,7 +36866,7 @@ function for deficient systems.
 @end table
 
 Use the command @samp{./configure --help} to see the full list of
-options that @command{configure} supplies.
+options supplied by @command{configure}.
 
 @node Configuration Philosophy
 @appendixsubsec The Configuration Process
@@ -36564,19 +36900,19 @@ facts about your operating system.  For example, there may not be an
 @cindex @code{custom.h} file
 It is possible for your C compiler to lie to @command{configure}. It may
 do so by not exiting with an error when a library function is not
-available.  To get around this, edit the file @file{custom.h}.
+available.  To get around this, edit the @file{custom.h} file.
 Use an @samp{#ifdef} that is appropriate for your system, and either
 @code{#define} any constants that @command{configure} should have defined but
 didn't, or @code{#undef} any constants that @command{configure} defined and
-should not have.  @file{custom.h} is automatically included by
-@file{config.h}.
+should not have.  The @file{custom.h} file is automatically included by
+the @file{config.h} file.
 
 It is also possible that the @command{configure} program generated by
 Autoconf will not work on your system in some other fashion.
-If you do have a problem, the file @file{configure.ac} is the input for
+If you do have a problem, the @file{configure.ac} file is the input for
 Autoconf.  You may be able to change this file and generate a
 new version of @command{configure} that works on your system
-(@pxref{Bugs},
+(@DBPXREF{Bugs}
 for information on how to report problems in configuring @command{gawk}).
 The same mechanism may be used to send in updates to @file{configure.ac}
 and/or @file{custom.h}.
@@ -36610,13 +36946,13 @@ running MS-DOS, any version of MS-Windows, or OS/2.
 running MS-DOS and any version of MS-Windows.
 @end ifset
 In this @value{SECTION}, the term ``Windows32''
-refers to any of Microsoft Windows-95/98/ME/NT/2000/XP/Vista/7/8.
+refers to any of Microsoft Windows 95/98/ME/NT/2000/XP/Vista/7/8.
 
 The limitations of MS-DOS (and MS-DOS shells under the other operating
-systems) has meant that various ``DOS extenders'' are often used with
+systems) have meant that various ``DOS extenders'' are often used with
 programs such as @command{gawk}.  The varying capabilities of Microsoft
 Windows 3.1 and Windows32 can add to the confusion.  For an overview
-of the considerations, please refer to @file{README_d/README.pc} in
+of the considerations, refer to @file{README_d/README.pc} in
 the distribution.
 
 @menu
@@ -36779,7 +37115,7 @@ Ancient OS/2 ports of GNU @command{make} are not able to handle
 the Makefiles of this package.  If you encounter any problems with
 @command{make}, try GNU Make 3.79.1 or later versions.  You should
 find the latest version on
-@uref{ftp://hobbes.nmsu.edu/pub/os2/}.@footnote{As of May, 2014,
+@uref{ftp://hobbes.nmsu.edu/pub/os2/}.@footnote{As of November 2014,
 this site is still there, but the author could not find a package
 for GNU Make.}
 @end quotation
@@ -36812,9 +37148,7 @@ multibyte functionality is not available.
 
 @node PC Using
 @appendixsubsubsec Using @command{gawk} on PC Operating Systems
-@c STARTOFRANGE opgawx
 @cindex operating systems, PC, @command{gawk} on
-@c STARTOFRANGE pcgawon
 @cindex PC operating systems, @command{gawk} on
 
 Under MS-DOS and MS-Windows, the Cygwin and MinGW environments support
@@ -36828,8 +37162,8 @@ EMX (OS/2 only) supports at least the @samp{|&} operator.
 @cindex search paths, for source files
 @cindex @command{gawk}, MS-DOS version of
 @cindex @command{gawk}, MS-Windows version of
-@cindex @code{;} (semicolon), @code{AWKPATH} variable and
-@cindex semicolon (@code{;}), @code{AWKPATH} variable and
+@cindex @code{;} (semicolon), @env{AWKPATH} variable and
+@cindex semicolon (@code{;}), @env{AWKPATH} variable and
 @cindex @env{AWKPATH} environment variable
 The MS-DOS and MS-Windows versions of @command{gawk} search for
 program files as described in @ref{AWKPATH Variable}.  However,
@@ -36874,7 +37208,7 @@ Under MS-Windows, OS/2 and MS-DOS,
 Under MS-Windows and MS-DOS,
 @end ifset
 @command{gawk} (and many other text programs) silently
-translate end-of-line @samp{\r\n} to @samp{\n} on input and @samp{\n}
+translates end-of-line @samp{\r\n} to @samp{\n} on input and @samp{\n}
 to @samp{\r\n} on output.  A special @code{BINMODE} variable @value{COMMONEXT}
 allows control over these translations and is interpreted as follows:
 
@@ -36908,7 +37242,7 @@ Setting @code{BINMODE} for standard input or
 standard output is accomplished by using an
 appropriate @samp{-v BINMODE=@var{N}} option on the command line.
 @code{BINMODE} is set at the time a file or pipe is opened and cannot be
-changed mid-stream.
+changed midstream.
 
 The name @code{BINMODE} was chosen to match @command{mawk}
 (@pxref{Other Versions}).
@@ -36964,8 +37298,8 @@ moved into the @code{BEGIN} rule.
 
 @command{gawk} can be built and used ``out of the box'' under MS-Windows
 if you are using the @uref{http://www.cygwin.com, Cygwin environment}.
-This environment provides an excellent simulation of GNU/Linux, using the
-GNU tools, such as Bash, the GNU Compiler Collection (GCC), GNU Make,
+This environment provides an excellent simulation of GNU/Linux, using
+Bash, GCC, GNU Make,
 and other GNU programs.  Compilation and installation for Cygwin is the
 same as for a Unix system:
 
@@ -36984,12 +37318,12 @@ and then the @samp{make} proceeds as usual.
 @appendixsubsubsec Using @command{gawk} In The MSYS Environment
 
 In the MSYS environment under MS-Windows, @command{gawk} automatically
-uses binary mode for reading and writing files.  Thus there is no
+uses binary mode for reading and writing files.  Thus, there is no
 need to use the @code{BINMODE} variable.
 
 This can cause problems with other Unix-like components that have
 been ported to MS-Windows that expect @command{gawk} to do automatic
-translation of @code{"\r\n"}, since it won't.
+translation of @code{"\r\n"}, because it won't.
 
 @node VMS Installation
 @appendixsubsec Compiling and Installing @command{gawk} on Vax/VMS and OpenVMS
@@ -37048,19 +37382,19 @@ With ODS-5 volumes and extended parsing enabled, the case of the target
 parameter may need to be exact.
 
 @command{gawk} has been tested under VAX/VMS 7.3 and Alpha/VMS 7.3-1
-using Compaq C V6.4, and Alpha/VMS 7.3, Alpha/VMS 7.3-2, and IA64/VMS 8.3.
+using Compaq C V6.4, and under Alpha/VMS 7.3, Alpha/VMS 7.3-2, and IA64/VMS 8.3.
 The most recent builds used HP C V7.3 on Alpha VMS 8.3 and both
 Alpha and IA64 VMS 8.4 used HP C 7.3.@footnote{The IA64 architecture
 is also known as ``Itanium.''}
 
-@xref{VMS GNV}, for information on building
+@DBXREF{VMS GNV} for information on building
 @command{gawk} as a PCSI kit that is compatible with the GNV product.
 
 @node VMS Dynamic Extensions
 @appendixsubsubsec Compiling @command{gawk} Dynamic Extensions on VMS
 
 The extensions that have been ported to VMS can be built using one of
-the following commands.
+the following commands:
 
 @example
 $ @kbd{MMS/DESCRIPTION=[.vms]descrip.mms extensions}
@@ -37077,7 +37411,7 @@ $ @kbd{MMK/DESCRIPTION=[.vms]descrip.mms extensions}
 or a logical name to find the dynamic extensions.
 
 Dynamic extensions need to be compiled with the same compiler options for
-floating point, pointer size, and symbol name handling as were used
+floating-point, pointer size, and symbol name handling as were used
 to compile @command{gawk} itself.
 Alpha and Itanium should use IEEE floating point.  The pointer size is 32 bits,
 and the symbol name handling should be exact case with CRC shortening for
@@ -37096,7 +37430,7 @@ For VAX:
 /name=(as_is,short)
 @end example
 
-Compile time macros need to be defined before the first VMS-supplied
+Compile-time macros need to be defined before the first VMS-supplied
 header file is included, as follows:
 
 @example
@@ -37143,7 +37477,7 @@ If your @command{gawk} was installed by a PCSI kit into the
 @file{GNV$GNU:[vms_help]gawk.hlp}.
 
 The PCSI kit also installs a @file{GNV$GNU:[vms_bin]gawk_verb.cld} file
-which can be used to add @command{gawk} and @command{awk} as DCL commands.
+that can be used to add @command{gawk} and @command{awk} as DCL commands.
 
 For just the current process you can use:
 
@@ -37152,7 +37486,7 @@ $ @kbd{set command gnv$gnu:[vms_bin]gawk_verb.cld}
 @end example
 
 Or the system manager can use @file{GNV$GNU:[vms_bin]gawk_verb.cld} to
-add the @command{gawk} and @command{awk} to the system wide @samp{DCLTABLES}.
+add the @command{gawk} and @command{awk} to the system-wide @samp{DCLTABLES}.
 
 The DCL syntax is documented in the @file{gawk.hlp} file.
 
@@ -37207,7 +37541,7 @@ Note that uppercase and mixed-case text must be quoted.
 The VMS port of @command{gawk} includes a @code{DCL}-style interface in addition
 to the original shell-style interface (see the help entry for details).
 One side effect of dual command-line parsing is that if there is only a
-single parameter (as in the quoted string program above), the command
+single parameter (as in the quoted string program), the command
 becomes ambiguous.  To work around this, the normally optional @option{--}
 flag is required to force Unix-style parsing rather than @code{DCL} parsing.  If any
 other dash-type options (or multiple parameters such as @value{DF}s to
@@ -37218,14 +37552,14 @@ The @code{exit} value is a Unix-style value and is encoded into a VMS exit
 status value when the program exits.
 
 The VMS severity bits will be set based on the @code{exit} value.
-A failure is indicated by 1 and VMS sets the @code{ERROR} status.
-A fatal error is indicated by 2 and VMS sets the @code{FATAL} status.
+A failure is indicated by 1, and VMS sets the @code{ERROR} status.
+A fatal error is indicated by 2, and VMS sets the @code{FATAL} status.
 All other values will have the @code{SUCCESS} status.  The exit value is
 encoded to comply with VMS coding standards and will have the
 @code{C_FACILITY_NO} of @code{0x350000} with the constant @code{0xA000}
 added to the number shifted over by 3 bits to make room for the severity codes.
 
-To extract the actual @command{gawk} exit code from the VMS status use:
+To extract the actual @command{gawk} exit code from the VMS status, use:
 
 @example
 unix_status = (vms_status .and. &x7f8) / 8
@@ -37244,7 +37578,7 @@ VAX/VMS floating point uses unbiased rounding. @xref{Round Function}.
 
 VMS reports time values in GMT unless one of the @code{SYS$TIMEZONE_RULE}
 or @code{TZ} logical names is set.  Older versions of VMS, such as VAX/VMS
-7.3 do not set these logical names.
+7.3, do not set these logical names.
 
 @c @cindex directory search
 @c @cindex path, search
@@ -37262,7 +37596,7 @@ translation and not a multitranslation @code{RMS} searchlist.
 
 The VMS GNV package provides a build environment similar to POSIX with ports
 of a collection of open source tools.  The @command{gawk} found in the GNV
-base kit is an older port.  Currently the GNV project is being reorganized
+base kit is an older port.  Currently, the GNV project is being reorganized
 to supply individual PCSI packages for each component.
 See @w{@uref{https://sourceforge.net/p/gnv/wiki/InstallingGNVPackages/}.}
 
@@ -37322,40 +37656,36 @@ $ @kbd{gawk :== $sys$common:[syshlp.examples.tcpip.snmp]gawk.exe}
 This is apparently @value{PVERSION} 2.15.6, which is extremely old. We
 recommend compiling and using the current version.
 
-@c ENDOFRANGE opgawx
-@c ENDOFRANGE pcgawon
 
 @node Bugs
 @appendixsec Reporting Problems and Bugs
-@cindex archeologists
+@cindex archaeologists
 @quotation
-@i{There is nothing more dangerous than a bored archeologist.}
-@author The Hitchhiker's Guide to the Galaxy
+@i{There is nothing more dangerous than a bored archaeologist.}
+@author Douglas Adams, @cite{The Hitchhiker's Guide to the Galaxy}
 @end quotation
 @c the radio show, not the book. :-)
 
-@c STARTOFRANGE dbugg
 @cindex debugging @command{gawk}, bug reports
-@c STARTOFRANGE tblgawb
 @cindex troubleshooting, @command{gawk}, bug reports
 If you have problems with @command{gawk} or think that you have found a bug,
-please report it to the developers; we cannot promise to do anything
+report it to the developers; we cannot promise to do anything,
 but we might well want to fix it.
 
-Before reporting a bug, please make sure you have really found a genuine bug.
+Before reporting a bug, make sure you have really found a genuine bug.
 Carefully reread the documentation and see if it says you can do
 what you're trying to do.  If it's not clear whether you should be able
 to do something or not, report that too; it's a bug in the documentation!
 
 Before reporting a bug or trying to fix it yourself, try to isolate it
 to the smallest possible @command{awk} program and input @value{DF} that
-reproduces the problem.  Then send us the program and @value{DF},
+reproduce the problem.  Then send us the program and @value{DF},
 some idea of what kind of Unix system you're using,
 the compiler you used to compile @command{gawk}, and the exact results
 @command{gawk} gave you.  Also say what you expected to occur; this helps
 us decide whether the problem is really in the documentation.
 
-Please include the version number of @command{gawk} you are using.
+Make sure to include the version number of @command{gawk} you are using.
 You can get this information with the command @samp{gawk --version}.
 
 @cindex @code{bug-gawk@@gnu.org} bug reporting address
@@ -37364,10 +37694,10 @@ You can get this information with the command @samp{gawk --version}.
 Once you have a precise problem description, send email to
 @EMAIL{bug-gawk@@gnu.org,bug-gawk at gnu dot org}.
 
-The @command{gawk} maintainers subscribe to this address and
+The @command{gawk} maintainers subscribe to this address, and
 thus they will receive your bug report.
 Although you can send mail to the maintainers directly,
-the bug reporting address is preferred since the
+the bug reporting address is preferred because the
 email list is archived at the GNU Project.
 @emph{All email must be in English. This is the only language
 understood in common by all the maintainers.}
@@ -37376,32 +37706,32 @@ understood in common by all the maintainers.}
 @quotation CAUTION
 Do @emph{not} try to report bugs in @command{gawk} by
 posting to the Usenet/Internet newsgroup @code{comp.lang.awk}.
-While the @command{gawk} developers do occasionally read this newsgroup,
-there is no guarantee that we will see your posting.  The steps described
-above are the only official recognized way for reporting bugs.
+The @command{gawk} developers do occasionally read this newsgroup,
+but there is no guarantee that we will see your posting.  The steps described
+here are the only officially recognized way for reporting bugs.
 Really.
 @end quotation
 
 @quotation NOTE
 Many distributions of GNU/Linux and the various BSD-based operating systems
 have their own bug reporting systems.  If you report a bug using your distribution's
-bug reporting system, @emph{please} also send a copy to
+bug reporting system, you should also send a copy to
 @EMAIL{bug-gawk@@gnu.org,bug-gawk at gnu dot org}.
 
-This is for two reasons.  First, while some distributions forward
+This is for two reasons.  First, although some distributions forward
 bug reports ``upstream'' to the GNU mailing list, many don't, so there is a good
 chance that the @command{gawk}  maintainers won't even see the bug report!  Second,
-mail to the GNU list is archived, and having everything at the GNU project
-keeps things self-contained and not dependant on other organizations.
+mail to the GNU list is archived, and having everything at the GNU Project
+keeps things self-contained and not dependent on other organizations.
 @end quotation
 
 Non-bug suggestions are always welcome as well.  If you have questions
 about things that are unclear in the documentation or are just obscure
 features, ask on the bug list; we will try to help you out if we can.
 
-If you find bugs in one of the non-Unix ports of @command{gawk}, please
-send an electronic mail message to the bug list, with a copy to the
-person who maintains that port.  They are named in the following list,
+If you find bugs in one of the non-Unix ports of @command{gawk},
+send an email to the bug list, with a copy to the
+person who maintains that port.  The maintainers are named in the following list,
 as well as in the @file{README} file in the @command{gawk} distribution.
 Information in the @file{README} file should be considered authoritative
 if it conflicts with this @value{DOCUMENT}.
@@ -37416,30 +37746,26 @@ The people maintaining the various @command{gawk} ports are:
 @cindex Robbins, Arnold
 @cindex Zaretskii, Eli
 @multitable {MS-Windows with MinGW} {123456789012345678901234567890123456789001234567890}
-@item Unix and POSIX systems @tab Arnold Robbins, @EMAIL{arnold@@skeeve.com,arnold at skeeve dot com}.
+@item Unix and POSIX systems @tab Arnold Robbins, @EMAIL{arnold@@skeeve.com,arnold at skeeve dot com}
 
-@item MS-DOS with DJGPP @tab Scott Deifik, @EMAIL{scottd.mail@@sbcglobal.net,scottd dot mail at sbcglobal dot net}.
+@item MS-DOS with DJGPP @tab Scott Deifik, @EMAIL{scottd.mail@@sbcglobal.net,scottd dot mail at sbcglobal dot net}
 
-@item MS-Windows with MinGW @tab Eli Zaretskii, @EMAIL{eliz@@gnu.org,eliz at gnu dot org}.
+@item MS-Windows with MinGW @tab Eli Zaretskii, @EMAIL{eliz@@gnu.org,eliz at gnu dot org}
 
 @c Leave this in the print version on purpose.
 @c OS/2 is not mentioned anywhere else in the print version though.
-@item OS/2 @tab Andreas Buening, @EMAIL{andreas.buening@@nexgo.de,andreas dot buening at nexgo dot de}.
+@item OS/2 @tab Andreas Buening, @EMAIL{andreas.buening@@nexgo.de,andreas dot buening at nexgo dot de}
 
-@item VMS @tab John Malmberg, @EMAIL{wb8tyw@@qsl.net,wb8tyw at qsl.net}.
+@item VMS @tab John Malmberg, @EMAIL{wb8tyw@@qsl.net,wb8tyw at qsl.net}
 
-@item z/OS (OS/390) @tab Dave Pitts, @EMAIL{dpitts@@cozx.com,dpitts at cozx dot com}.
+@item z/OS (OS/390) @tab Dave Pitts, @EMAIL{dpitts@@cozx.com,dpitts at cozx dot com}
 @end multitable
 
-If your bug is also reproducible under Unix, please send a copy of your
-report to the @EMAIL{bug-gawk@@gnu.org,bug-gawk at gnu dot org} email
-list as well.
-@c ENDOFRANGE dbugg
-@c ENDOFRANGE tblgawb
+If your bug is also reproducible under Unix, send a copy of your
+report to the @EMAIL{bug-gawk@@gnu.org,bug-gawk at gnu dot org} email list as well.
 
 @node Other Versions
 @appendixsec Other Freely Available @command{awk} Implementations
-@c STARTOFRANGE awkim
 @cindex @command{awk}, implementations
 @ignore
 From: emory!amc.com!brennan (Michael Brennan)
@@ -37451,7 +37777,7 @@ Date: Wed, 4 Sep 1996 08:11:48 -0700 (PDT)
 @cindex Brennan, Michael
 @ifnotdocbook
 @quotation
-@i{It's kind of fun to put comments like this in your awk code.}@*
+@i{It's kind of fun to put comments like this in your awk code:}@*
 @ @ @ @ @ @ @code{// Do C++ comments work? answer: yes! of course}
 @author Michael Brennan
 @end quotation
@@ -37464,8 +37790,6 @@ Date: Wed, 4 Sep 1996 08:11:48 -0700 (PDT)
 </blockquote>
 @end docbook
 
-
-
 There are a number of other freely available @command{awk} implementations.
 This @value{SECTION} briefly describes where to get them:
 
@@ -37478,7 +37802,7 @@ This @value{SECTION} briefly describes where to get them:
 Brian Kernighan, one of the original designers of Unix @command{awk},
 has made his implementation of
 @command{awk} freely available.
-You can retrieve this version via the World Wide Web from
+You can retrieve this version via
 @uref{http://www.cs.princeton.edu/~bwk, his home page}.
 It is available in several archive formats:
 
@@ -37494,14 +37818,14 @@ It is available in several archive formats:
 @end table
 
 @cindex @command{git} utility
-You can also retrieve it from Git Hub:
+You can also retrieve it from GitHub:
 
 @example
 git clone git://github.com/onetrueawk/awk bwkawk
 @end example
 
 @noindent
-The above command creates a copy of the @uref{http://www.git-scm.com, Git}
+This command creates a copy of the @uref{http://git-scm.com, Git}
 repository in a directory named @file{bwkawk}.  If you leave that argument
 off the @command{git} command line, the repository copy is created in a
 directory named @file{awk}.
@@ -37509,9 +37833,13 @@ directory named @file{awk}.
 This version requires an ISO C (1990 standard) compiler; the C compiler
 from GCC (the GNU Compiler Collection) works quite nicely.
 
-@xref{Common Extensions},
+@DBXREF{Common Extensions}
 for a list of extensions in this @command{awk} that are not in POSIX @command{awk}.
 
+As a side note, Dan Bornstein has created a Git repository tracking
+all the versions of BWK @command{awk} that he could find. It's
+available at @uref{git://github.com/danfuzz/one-true-awk}.
+
 @cindex Brennan, Michael
 @cindex @command{mawk} utility
 @cindex source code, @command{mawk}
@@ -37541,7 +37869,7 @@ Once you have it,
 is similar to @command{gawk}'s
 (@pxref{Unix Installation}).
 
-@xref{Common Extensions},
+@DBXREF{Common Extensions}
 for a list of extensions in @command{mawk} that are not in POSIX @command{awk}.
 
 @cindex Sumner, Andrew
@@ -37550,7 +37878,7 @@ for a list of extensions in @command{mawk} that are not in POSIX @command{awk}.
 @item @command{awka}
 Written by Andrew Sumner,
 @command{awka} translates @command{awk} programs into C, compiles them,
-and links them with a library of functions that provides the core
+and links them with a library of functions that provide the core
 @command{awk} functionality.
 It also has a number of extensions.
 
@@ -37562,7 +37890,7 @@ To get @command{awka}, go to @url{http://sourceforge.net/projects/awka}.
 @c andrewsumner@@yahoo.net
 
 The project seems to be frozen; no new code changes have been made
-since approximately 2003.
+since approximately 2001.
 
 @cindex Beebe, Nelson H.F.@:
 @cindex @command{pawk} (profiling version of Brian Kernighan's @command{awk})
@@ -37571,17 +37899,17 @@ since approximately 2003.
 Nelson H.F.@: Beebe at the University of Utah has modified
 BWK @command{awk} to provide timing and profiling information.
 It is different from @command{gawk} with the @option{--profile} option
-(@pxref{Profiling}),
+(@pxref{Profiling})
 in that it uses CPU-based profiling, not line-count
 profiling.  You may find it at either
 @uref{ftp://ftp.math.utah.edu/pub/pawk/pawk-20030606.tar.gz}
 or
 @uref{http://www.math.utah.edu/pub/pawk/pawk-20030606.tar.gz}.
 
-@item Busybox Awk
-@cindex Busybox Awk
-@cindex source code, Busybox Awk
-Busybox is a GPL-licensed program providing small versions of many
+@item BusyBox @command{awk}
+@cindex BusyBox Awk
+@cindex source code, BusyBox Awk
+BusyBox is a GPL-licensed program providing small versions of many
 applications within a single executable. It is aimed at embedded systems.
 It includes a full implementation of POSIX @command{awk}.  When building
 it, be careful not to do @samp{make install} as it will overwrite
@@ -37593,7 +37921,7 @@ information, see the @uref{http://busybox.net, project's home page}.
 @cindex source code, Solaris @command{awk}
 @item The OpenSolaris POSIX @command{awk}
 The versions of @command{awk} in @file{/usr/xpg4/bin} and
-@file{/usr/xpg6/bin} on Solaris are more-or-less POSIX-compliant.
+@file{/usr/xpg6/bin} on Solaris are more or less POSIX-compliant.
 They are based on the @command{awk} from Mortice Kern Systems for PCs.
 We were able to make this code compile and work under GNU/Linux
 with 1--2 hours of work.  Making it more generally portable (using
@@ -37603,8 +37931,8 @@ has not been done, at least to our knowledge.
 @cindex Illumos
 @cindex Illumos, POSIX-compliant @command{awk}
 @cindex source code, Illumos @command{awk}
-The source code used to be available from the OpenSolaris web site.
-However, that project was ended and the web site shut down.  Fortunately, the
+The source code used to be available from the OpenSolaris website.
+However, that project was ended and the website shut down.  Fortunately, the
 @uref{http://wiki.illumos.org/display/illumos/illumos+Home, Illumos project}
 makes this implementation available.  You can view the files one at a time from
 @uref{https://github.com/joyent/illumos-joyent/blob/master/usr/src/cmd/awk_xpg4}.
@@ -37623,7 +37951,7 @@ from POSIX @command{awk}.  More information is available on the
 @cindex libmawk
 @cindex source code, libmawk
 This is an embeddable @command{awk} interpreter derived from
-@command{mawk}. For more information see
+@command{mawk}. For more information, see
 @uref{http://repo.hu/projects/libmawk/}.
 
 @item @code{pawk}
@@ -37634,10 +37962,10 @@ features to Python. See @uref{https://github.com/alecthomas/pawk}
 for more information. (This is not related to Nelson Beebe's
 modified version of BWK @command{awk}, described earlier.)
 
-@item @w{QSE Awk}
-@cindex QSE Awk
-@cindex source code, QSE Awk
-This is an embeddable @command{awk} interpreter. For more information
+@item @w{QSE @command{awk}}
+@cindex QSE @command{awk}
+@cindex source code, QSE @command{awk}
+This is an embeddable @command{awk} interpreter. For more information,
 see @uref{http://code.google.com/p/qse/} and @uref{http://awk.info/?tools/qse}.
 
 @item @command{QTawk}
@@ -37652,19 +37980,19 @@ including the manual and a download link.
 The project may also be frozen; no new code changes have been made
 since approximately 2008.
 
-@item Other Versions
-See also the @uref{http://en.wikipedia.org/wiki/Awk_language#Versions_and_implementations,
-Wikipedia article}, for information on additional versions.
+@item Other versions
+See also the ``Versions and implementations'' section of the
+@uref{http://en.wikipedia.org/wiki/Awk_language#Versions_and_implementations,
+Wikipedia article} on @command{awk} for information on additional versions.
 
 @end table
-@c ENDOFRANGE awkim
 
 @node Installation summary
 @appendixsec Summary
 
 @itemize @value{BULLET}
 @item
-The @command{gawk} distribution is available from GNU project's main
+The @command{gawk} distribution is available from the GNU Project's main
 distribution site, @code{ftp.gnu.org}.  The canonical build recipe is:
 
 @example
@@ -37676,34 +38004,30 @@ cd gawk-@value{VERSION}.@value{PATCHLEVEL}
 
 @item
 @command{gawk} may be built on non-POSIX systems as well. The currently
-supported systems are MS-Windows using DJGPP, MSYS, MinGW and Cygwin,
+supported systems are MS-Windows using DJGPP, MSYS, MinGW, and Cygwin,
 @ifclear FOR_PRINT
 OS/2 using EMX,
 @end ifclear
 and both Vax/VMS and OpenVMS.
-Instructions for each system are included in this @value{CHAPTER}.
+Instructions for each system are included in this @value{APPENDIX}.
 
 @item
 Bug reports should be sent via email to @email{bug-gawk@@gnu.org}.
-Bug reports should be in English, and should include the version of @command{gawk},
-how it was compiled, and a short program and @value{DF} which demonstrate
+Bug reports should be in English and should include the version of @command{gawk},
+how it was compiled, and a short program and @value{DF} that demonstrate
 the problem.
 
 @item
 There are a number of other freely available @command{awk}
-implementations.  Many are POSIX compliant; others are less so.
+implementations.  Many are POSIX-compliant; others are less so.
 
 @end itemize
 
-@c ENDOFRANGE gligawk
-@c ENDOFRANGE ingawk
 
 @ifclear FOR_PRINT
 @node Notes
 @appendix Implementation Notes
-@c STARTOFRANGE gawii
 @cindex @command{gawk}, implementation issues
-@c STARTOFRANGE impis
 @cindex implementation issues, @command{gawk}
 
 This appendix contains information mainly of interest to implementers and
@@ -37779,7 +38103,7 @@ However, if you want to modify @command{gawk} and contribute back your
 changes, you will probably wish to work with the development version.
 To do so, you will need to access the @command{gawk} source code
 repository.  The code is maintained using the
-@uref{http://git-scm.com/, Git distributed version control system}.
+@uref{http://git-scm.com, Git distributed version control system}.
 You will need to install it if your system doesn't have it.
 Once you have done so, use the command:
 
@@ -37808,11 +38132,8 @@ that has a Git plug-in for working with Git repositories.
 @node Adding Code
 @appendixsubsec Adding New Features
 
-@c STARTOFRANGE adfgaw
 @cindex adding, features to @command{gawk}
-@c STARTOFRANGE fadgaw
 @cindex features, adding to @command{gawk}
-@c STARTOFRANGE gawadf
 @cindex @command{gawk}, features, adding
 You are free to add any new features you like to @command{gawk}.
 However, if you want your changes to be incorporated into the @command{gawk}
@@ -37847,7 +38168,7 @@ for information on getting the latest version of @command{gawk}.)
 
 @item
 @ifnotinfo
-Follow the @uref{http://www.gnu.org/prep/standards/, @cite{GNU Coding Standards}}.
+Follow the @cite{GNU Coding Standards}.
 @end ifnotinfo
 @ifinfo
 See @inforef{Top, , Version, standards, GNU Coding Standards}.
@@ -37856,7 +38177,7 @@ This document describes how GNU software should be written. If you haven't
 read it, please do so, preferably @emph{before} starting to modify @command{gawk}.
 (The @cite{GNU Coding Standards} are available from
 the GNU Project's
-@uref{http://www.gnu.org/prep/standards_toc.html, web site}.
+@uref{http://www.gnu.org/prep/standards/, website}.
 Texinfo, Info, and DVI versions are also available.)
 
 @cindex @command{gawk}, coding style in
@@ -37979,9 +38300,6 @@ Although this sounds like a lot of work, please remember that while you
 may write the new code, I have to maintain it and support it. If it
 isn't possible for me to do that with a minimum of extra work, then I
 probably will not.
-@c ENDOFRANGE adfgaw
-@c ENDOFRANGE gawadf
-@c ENDOFRANGE fadgaw
 
 @node New Ports
 @appendixsubsec Porting @command{gawk} to a New Operating System
@@ -38115,7 +38433,6 @@ coding style and brace layout that suits your taste.
 @node Derived Files
 @appendixsubsec Why Generated Files Are Kept In Git
 
-@c STARTOFRANGE gawkgit
 @cindex Git, use of for @command{gawk} source code
 @c From emails written March 22, 2012, to the gawk developers list.
 
@@ -38304,7 +38621,6 @@ wget http://git.savannah.gnu.org/cgit/gawk.git/snapshot/gawk-@var{branchname}.ta
 
 @noindent
 to retrieve a snapshot of the given branch.
-@c ENDOFRANGE gawkgit
 
 @node Future Extensions
 @appendixsec Probable Future Extensions
@@ -38685,13 +39001,10 @@ of @command{gawk}, but it @emph{will} be removed in the next major release.
 
 @end itemize
 
-@c ENDOFRANGE impis
-@c ENDOFRANGE gawii
 
 @node Basic Concepts
 @appendix Basic Programming Concepts
 @cindex programming, concepts
-@c STARTOFRANGE procon
 @cindex programming, concepts
 
 This @value{APPENDIX} attempts to define some of the basic concepts
@@ -38929,7 +39242,6 @@ standard for C.  This standard became an ISO standard in 1990.
 In 1999, a revised ISO C standard was approved and released.
 Where it makes sense, POSIX @command{awk} is compatible with 1999 ISO C.
 
-@c ENDOFRANGE procon
 
 @node Glossary
 @unnumbered Glossary
@@ -38941,6 +39253,13 @@ pattern matches an input record, @command{awk} executes the
 rule's action.  Actions are always enclosed in braces.
 (@xref{Action Overview}.)
 
+@cindex Ada programming language
+@cindex programming languages, Ada
+@item Ada
+A programming language originally defined by the U.S.@: Department of
+Defense for embedded programming. It was designed to enforce good
+Software Engineering practices.
+
 @cindex Spencer, Henry
 @cindex @command{sed} utility
 @cindex amazing @command{awk} assembler (@command{aaa})
@@ -38952,13 +39271,6 @@ microcomputers.  It is a good example of a program that would have been
 better written in another language.
 You can get it from @uref{http://awk.info/?awk100/aaa}.
 
-@cindex Ada programming language
-@cindex programming languages, Ada
-@item Ada
-A programming language originally defined by the U.S.@: Department of
-Defense for embedded programming. It was designed to enforce good
-Software Engineering practices.
-
 @cindex amazingly workable formatter (@command{awf})
 @cindex @command{awf} (amazingly workable formatter) program
 @item Amazingly Workable Formatter (@command{awf})
@@ -38980,6 +39292,21 @@ languages.
 These standards often become international standards as well. See also
 ``ISO.''
 
+@item Argument
+An argument can be two different things.  It can be an option or a
+@value{FN} passed to a command while invoking it from the command line, or
+it can be something passed to a @dfn{function} inside a program, e.g.
+inside @command{awk}.
+
+In the latter case, an argument can be passed to a function in two ways.
+Either it is given to the called function by value, i.e., a copy of the
+value of the variable is made available to the called function, but the
+original variable cannot be modified by the function itself; or it is
+given by reference, i.e., a pointer to the interested variable is passed to
+the function, which can then directly modify it. In @command{awk}
+scalars are passed by value, and arrays are passed by reference.
+See ``Pass By Value/Reference.''
+
 @item Array
 A grouping of multiple values under the same name.
 Most languages just provide sequential arrays.
@@ -39021,6 +39348,25 @@ The GNU version of the standard shell
 @end ifinfo
 See also ``Bourne Shell.''
 
+@item Binary
+Base-two notation, where the digits are @code{0}--@code{1}. Since
+electronic circuitry works ``naturally'' in base 2 (just think of Off/On),
+everything inside a computer is calculated using base 2. Each digit
+represents the presence (or absence) of a power of 2 and is called a
+@dfn{bit}. So, for example, the base-two number @code{10101} is
+the same as decimal 21, ((1 x 16) + (1 x 4) + (1 x 1)).
+
+Since base-two numbers quickly become
+very long to read and write, they are usually grouped by 3 (i.e., they are
+read as octal numbers), or by 4 (i.e., they are read as hexadecimal
+numbers). There is no direct way to insert base 2 numbers in a C program.
+If need arises, such numbers are usually inserted as octal or hexadecimal
+numbers. The number of base-two digits that fit into registers used for
+representing integer numbers in computers is a rough indication of the
+computing power of the computer itself.  Most computers nowadays use 64
+bits for representing integer numbers in their registers, but 32-bit,
+16-bit and 8-bit registers have been widely used in the past.
+@xref{Nondecimal-numbers}.
 @item Bit
 Short for ``Binary Digit.''
 All values in computer memory ultimately reduce to binary digits: values
@@ -39047,6 +39393,24 @@ originally written by Steven R.@: Bourne at Bell Laboratories.
 Many shells (Bash, @command{ksh}, @command{pdksh}, @command{zsh}) are
 generally upwardly compatible with the Bourne shell.
 
+@item Braces
+The characters @samp{@{} and @samp{@}}.  Braces are used in
+@command{awk} for delimiting actions, compound statements, and function
+bodies.
+
+@item Bracket Expression
+Inside a @dfn{regular expression}, an expression included in square
+brackets, meant to designate a single character as belonging to a
+specified character class. A bracket expression can contain a list of one
+or more characters, like @samp{[abc]}, a range of characters, like
+@samp{[A-Z]}, or a name, delimited by @samp{:}, that designates a known set
+of characters, like @samp{[:digit:]}. The form of bracket expression
+enclosed between @samp{:} is independent of the underlying representation
+of the character themselves, which could utilize the ASCII, ECBDIC, or
+Unicode codesets, depending on the architecture of the computer system, and on
+localization.
+See also ``Regular Expression.''
+
 @item Built-in Function
 The @command{awk} language provides built-in functions that perform various
 numerical, I/O-related, and string computations.  Examples are
@@ -39092,11 +39456,6 @@ are the variables that have special meaning to @command{gawk}.
 Changing some of them affects @command{awk}'s running environment.
 (@xref{Built-in Variables}.)
 
-@item Braces
-The characters @samp{@{} and @samp{@}}.  Braces are used in
-@command{awk} for delimiting actions, compound statements, and function
-bodies.
-
 @item C
 The system programming language that most GNU software is written in.  The
 @command{awk} programming language has C-like syntax, and this @value{DOCUMENT}
@@ -39105,9 +39464,25 @@ points out similarities between @command{awk} and C when appropriate.
 In general, @command{gawk} attempts to be as similar to the 1990 version
 of ISO C as makes sense.
 
+@item C Shell
+The C Shell (@command{csh} or its improved version, @command{tcsh}) is a Unix shell that was
+created by Bill Joy in the late 1970s. The C shell was differentiated from
+other shells by its interactive features and overall style, which
+looks more like C. The C Shell is not backward compatible with the Bourne
+Shell, so special attention is required when converting scripts
+written for other Unix shells to the C shell, especially with regard to the management of
+shell variables.
+See also ``Bourne Shell.''
+
 @item C++
 A popular object-oriented programming language derived from C.
 
+@item Character Class
+See ``Bracket Expression.''
+
+@item Character List
+See ``Bracket Expression.''
+
 @cindex ASCII
 @cindex ISO 8859-1
 @cindex ISO Latin-1
@@ -39131,7 +39506,59 @@ A preprocessor for @command{pic} that reads descriptions of molecules
 and produces @command{pic} input for drawing them.
 It was written in @command{awk}
 by Brian Kernighan and Jon Bentley, and is available from
-@uref{http://netlib.sandia.gov/netlib/typesetting/chem.gz}.
+@uref{http://netlib.org/typesetting/chem}.
+
+@item Comparison Expression
+A relation that is either true or false, such as @samp{a < b}.
+Comparison expressions are used in @code{if}, @code{while}, @code{do},
+and @code{for}
+statements, and in patterns to select which input records to process.
+(@xref{Typing and Comparison}.)
+
+@cindex compiled programs
+@item Compiler
+A program that translates human-readable source code into
+machine-executable object code.  The object code is then executed
+directly by the computer.
+See also ``Interpreter.''
+
+@item Complemented Bracket Expression
+The negation of a @dfn{bracket expression}.  All that is @emph{not}
+described by a given bracket expression. The symbol @samp{^} precedes
+the negated bracket expression.  E.g.: @samp{[[^:digit:]}
+designates whatever character is not a digit. @samp{[^bad]}
+designates whatever character is not one of the letters @samp{b}, @samp{a},
+or @samp{d}.
+See ``Bracket Expression.''
+
+@item Compound Statement
+A series of @command{awk} statements, enclosed in curly braces.  Compound
+statements may be nested.
+(@xref{Statements}.)
+
+@item Computed Regexps
+See ``Dynamic Regular Expressions.''
+
+@item Concatenation
+Concatenating two strings means sticking them together, one after another,
+producing a new string.  For example, the string @samp{foo} concatenated with
+the string @samp{bar} gives the string @samp{foobar}.
+(@xref{Concatenation}.)
+
+@item Conditional Expression
+An expression using the @samp{?:} ternary operator, such as
+@samp{@var{expr1} ? @var{expr2} : @var{expr3}}.  The expression
+@var{expr1} is evaluated; if the result is true, the value of the whole
+expression is the value of @var{expr2}; otherwise the value is
+@var{expr3}.  In either case, only one of @var{expr2} and @var{expr3}
+is evaluated. (@xref{Conditional Exp}.)
+
+@item Control Statement
+A control statement is an instruction to perform a given operation or a set
+of operations inside an @command{awk} program, if a given condition is
+true. Control statements are: @code{if}, @code{for}, @code{while}, and
+@code{do}
+(@pxref{Statements}).
 
 @cindex McIlroy, Doug
 @cindex cookie
@@ -39181,39 +39608,6 @@ Doug
 @item Coprocess
 A subordinate program with which two-way communications is possible.
 
-@cindex compiled programs
-@item Compiler
-A program that translates human-readable source code into
-machine-executable object code.  The object code is then executed
-directly by the computer.
-See also ``Interpreter.''
-
-@item Compound Statement
-A series of @command{awk} statements, enclosed in curly braces.  Compound
-statements may be nested.
-(@xref{Statements}.)
-
-@item Concatenation
-Concatenating two strings means sticking them together, one after another,
-producing a new string.  For example, the string @samp{foo} concatenated with
-the string @samp{bar} gives the string @samp{foobar}.
-(@xref{Concatenation}.)
-
-@item Conditional Expression
-An expression using the @samp{?:} ternary operator, such as
-@samp{@var{expr1} ? @var{expr2} : @var{expr3}}.  The expression
-@var{expr1} is evaluated; if the result is true, the value of the whole
-expression is the value of @var{expr2}; otherwise the value is
-@var{expr3}.  In either case, only one of @var{expr2} and @var{expr3}
-is evaluated. (@xref{Conditional Exp}.)
-
-@item Comparison Expression
-A relation that is either true or false, such as @samp{a < b}.
-Comparison expressions are used in @code{if}, @code{while}, @code{do},
-and @code{for}
-statements, and in patterns to select which input records to process.
-(@xref{Typing and Comparison}.)
-
 @item Curly Braces
 See ``Braces.''
 
@@ -39259,15 +39653,15 @@ ordinary expression.  It could be a string constant, such as
 @code{"foo"}, but it may also be an expression whose value can vary.
 (@xref{Computed Regexps}.)
 
+@item Empty String
+See ``Null String.''
+
 @item Environment
 A collection of strings, of the form @samp{@var{name}=@var{val}}, that each
 program has available to it. Users generally place values into the
 environment in order to provide information to various programs. Typical
 examples are the environment variables @env{HOME} and @env{PATH}.
 
-@item Empty String
-See ``Null String.''
-
 @cindex epoch, definition of
 @item Epoch
 The date used as the ``beginning of time'' for timestamps.
@@ -39320,19 +39714,15 @@ Format strings control the appearance of output in the
 are controlled by the format strings contained in the predefined variables
 @code{CONVFMT} and @code{OFMT}. (@xref{Control Letters}.)
 
+@item Fortran
+Shorthand for FORmula TRANslator, one of the first programming languages
+available for scientific calculations. It was created by John Backus,
+and has been available since 1957. It is still in use today.
+
 @item Free Documentation License
 This document describes the terms under which this @value{DOCUMENT}
 is published and may be copied. (@xref{GNU Free Documentation License}.)
 
-@item Function
-A specialized group of statements used to encapsulate general
-or program-specific tasks.  @command{awk} has a number of built-in
-functions, and also allows you to define your own.
-(@xref{Functions}.)
-
-@item FSF
-See ``Free Software Foundation.''
-
 @cindex FSF (Free Software Foundation)
 @cindex Free Software Foundation (FSF)
 @cindex Stallman, Richard
@@ -39342,6 +39732,26 @@ to the production and distribution of freely distributable software.
 It was founded by Richard M.@: Stallman, the author of the original
 Emacs editor.  GNU Emacs is the most widely used version of Emacs today.
 
+@item FSF
+See ``Free Software Foundation.''
+
+@item Function
+A part of an @command{awk} program that can be invoked from every point of
+the program, to perform a task.  @command{awk} has several built-in
+functions.
+Users can define their own functions in every part of the program.
+Function can be recursive, i.e., they may invoke themselves.
+@xref{Functions}.
+In @command{gawk} it is also possible to have functions shared
+among different programs, and included where required using the
+@code{@@include} directive
+(@pxref{Include Files}).
+In @command{gawk} the name of the function that should be invoked
+can be generated at run time, i.e., dynamically.
+The @command{gawk} extension API provides constructor functions
+(@pxref{Constructor Functions}).
+
+
 @item @command{gawk}
 The GNU implementation of @command{awk}.
 
@@ -39464,6 +39874,12 @@ meaning.  Keywords are reserved and may not be used as variable names.
 and
 @code{while}.
 
+@item Korn Shell
+The Korn Shell (@command{ksh}) is a Unix shell which was developed by David Korn at Bell
+Laboratories in the early 1980s. The Korn Shell is backward-compatible with the Bourne
+shell and includes many features of the C shell.
+See also ``Bourne Shell.''
+
 @cindex LGPL (Lesser General Public License)
 @cindex Lesser General Public License (LGPL)
 @cindex GNU Lesser General Public License
@@ -39472,12 +39888,12 @@ This document describes the terms under which binary library archives
 or shared objects,
 and their source code may be distributed.
 
-@item Linux
-See ``GNU/Linux.''
-
 @item LGPL
 See ``Lesser General Public License.''
 
+@item Linux
+See ``GNU/Linux.''
+
 @item Localization
 The process of providing the data necessary for an
 internationalized program to work in a particular language.
@@ -39503,6 +39919,14 @@ Characters used within a regexp that do not stand for themselves.
 Instead, they denote regular expression operations, such as repetition,
 grouping, or alternation.
 
+@item Nesting
+Nesting is where information is organized in layers, or where objects
+contain other similar objects.
+In @command{gawk} the @code{@@include}
+directive can be nested. The ``natural'' nesting of arithmetic and
+logical operations can be changed using parentheses
+(@pxref{Precedence}).
+
 @item No-op
 An operation that does nothing.
 
@@ -39523,6 +39947,11 @@ Octal numbers are written in C using a leading @samp{0},
 to indicate their base.  Thus, @code{013} is 11 ((1 x 8) + 3).
 @xref{Nondecimal-numbers}.
 
+@item Output Record
+A single chunk of data that is written out by @command{awk}.  Usually, an
+@command{awk} output record consists of one or more lines of text.
+@xref{Records}.
+
 @item Pattern
 Patterns tell @command{awk} which input records are interesting to which
 rules.
@@ -39537,6 +39966,9 @@ An acronym describing what is possibly the most frequent
 source of computer usage problems. (Problem Exists Between
 Keyboard And Chair.)
 
+@item Plug-in
+See ``Extensions.''
+
 @item POSIX
 The name for a series of standards
 that specify a Portable Operating System interface.  The ``IX'' denotes
@@ -39561,6 +39993,9 @@ A sequence of consecutive lines from the input file(s).  A pattern
 can specify ranges of input lines for @command{awk} to process or it can
 specify single lines. (@xref{Pattern Overview}.)
 
+@item Record
+See ``Input record'' and ``Output record.''
+
 @item Recursion
 When a function calls itself, either directly or indirectly.
 If this is clear, stop, and proceed to the next entry.
@@ -39578,6 +40013,15 @@ operators.
 (@xref{Getline},
 and @ref{Redirection}.)
 
+@item Reference Counts
+An internal mechanism in @command{gawk} to minimize the amount of memory
+needed to store the value of string variables. If the value assumed by
+a variable is used in more than one place, only one copy of the value
+itself is kept, and the associated reference count is increased when the
+same value is used by an additional variable, and decresed when the related
+variable is no longer in use. When the reference count goes to zero,
+the memory space used to store the value of the variable is freed.
+
 @item Regexp
 See ``Regular Expression.''
 
@@ -39595,6 +40039,15 @@ slashes, such as @code{/foo/}.  This regular expression is chosen
 when you write the @command{awk} program and cannot be changed during
 its execution. (@xref{Regexp Usage}.)
 
+@item Regular Expression Operators
+See ``Metacharacters.''
+
+@item Rounding
+Rounding the result of an arithmetic operation can be tricky.
+More than one way of rounding exists, and in @command{gawk}
+it is possible to choose which method should be used in a program.
+@xref{Setting the rounding mode}.
+
 @item Rule
 A segment of an @command{awk} program that specifies how to process single
 input records.  A rule consists of a @dfn{pattern} and an @dfn{action}.
@@ -39615,12 +40068,12 @@ Regular variables are scalars; arrays and functions are not.
 In @command{gawk}, a list of directories to search for @command{awk} program source files.
 In the shell, a list of directories to search for executable programs.
 
-@item Seed
-The initial value, or starting point, for a sequence of random numbers.
-
 @item @command{sed}
 See ``Stream Editor.''
 
+@item Seed
+The initial value, or starting point, for a sequence of random numbers.
+
 @item Shell
 The command interpreter for Unix and POSIX-compliant systems.
 The shell works both interactively, and as a programming language
@@ -39654,6 +40107,12 @@ A @value{FN} interpreted internally by @command{gawk}, instead of being handed
 directly to the underlying operating system---for example, @file{/dev/stderr}.
 (@xref{Special Files}.)
 
+@item Statement
+An expression inside an @command{awk} program in the action part
+of a pattern--action rule, or inside an
+@command{awk} function. A statement can be a variable assignment,
+an array operation, a loop, etc.
+
 @item Stream Editor
 A program that reads records from an input stream and processes them one
 or more at a time.  This is in contrast with batch programs, which may
@@ -39704,9 +40163,14 @@ This is standard time in Greenwich, England, which is used as a
 reference time for day and date calculations.
 See also ``Epoch'' and ``GMT.''
 
+@item Variable
+A name for a value. In @command{awk}, variables may be either scalars
+or arrays.
+
 @item Whitespace
 A sequence of space, TAB, or newline characters occurring inside an input
 record or a string.
+
 @end table
 
 @end ifclear
@@ -39722,7 +40186,7 @@ record or a string.
 @end docbook
 
 @c This file is intended to be included within another document,
-@c hence no sectioning command or @node.  
+@c hence no sectioning command or @node.
 
 @display
 Copyright @copyright{} 2007 Free Software Foundation, Inc. @url{http://fsf.org/}
@@ -39944,7 +40408,7 @@ terms of section 4, provided that you also meet all of these
 conditions:
 
 @enumerate a
-@item 
+@item
 The work must carry prominent notices stating that you modified it,
 and giving a relevant date.
 
@@ -40394,7 +40858,7 @@ state the exclusion of warranty; and each file should have at least
 the ``copyright'' line and a pointer to where the full notice is found.
 
 @smallexample
-@var{one line to give the program's name and a brief idea of what it does.}  
+@var{one line to give the program's name and a brief idea of what it does.}
 Copyright (C) @var{year} @var{name of author}
 
 This program is free software: you can redistribute it and/or modify
@@ -40417,7 +40881,7 @@ If the program does terminal interaction, make it output a short
 notice like this when it starts in an interactive mode:
 
 @smallexample
-@var{program} Copyright (C) @var{year} @var{name of author} 
+@var{program} Copyright (C) @var{year} @var{name of author}
 This program comes with ABSOLUTELY NO WARRANTY; for details type @samp{show w}.
 This is free software, and you are welcome to redistribute it
 under certain conditions; type @samp{show c} for details.
@@ -41101,3 +41565,4 @@ But to use it you have to say
 which sorta sucks.
 
 TODO:
+Check that all dark corners are indexed properly.