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diff --git a/doc/gawk.texi b/doc/gawk.texi index ad2e6558..ca74e8ba 100644 --- a/doc/gawk.texi +++ b/doc/gawk.texi @@ -303,15 +303,15 @@ ISBN 1-882114-28-0 @* @page @w{ } @sp 9 -@center @i{To Miriam, for making me complete.} +@center @i{To my parents, for their love, and for the wonderful +example they set for me.} @sp 1 -@center @i{To Chana, for the joy you bring us.} +@center @i{To my wife Miriam, for making me complete. +Thank you for building your life together with me.} @sp 1 -@center @i{To Rivka, for the exponential increase.} +@center @i{To our children Chana, Rivka, Nachum and Malka, +for enrichening our lives in innumerable ways.} @sp 1 -@center @i{To Nachum, for the added dimension.} -@sp 1 -@center @i{To Malka, for the new beginning.} @w{ } @page @w{ } @@ -321,13 +321,12 @@ ISBN 1-882114-28-0 @* @docbook <dedication> -<simplelist> -<member>To Miriam, for making me complete.</member> -<member>To Chana, for the joy you bring us.</member> -<member>To Rivka, for the exponential increase.</member> -<member>To Nachum, for the added dimension.</member> -<member>To Malka, for the new beginning.</member> -</simplelist> +<para>To my parents, for their love, and for the wonderful +example they set for me.</para> +<para>To my wife Miriam, for making me complete. +Thank you for building your life together with me.</para> +<para>To our children Chana, Rivka, Nachum and Malka, +for enrichening our lives in innumerable ways.</para> </dedication> @end docbook @@ -420,7 +419,7 @@ particular records in a file and perform operations upon them. * One-shot:: Running a short throwaway @command{awk} program. * Read Terminal:: Using no input files (input from - terminal instead). + the keyboard instead). * Long:: Putting permanent @command{awk} programs in files. * Executable Scripts:: Making self-contained @command{awk} @@ -1119,7 +1118,7 @@ The GNU implementation of @command{awk} is called @command{gawk}; if you invoke it with the proper options or environment variables (@pxref{Options}), it is fully compatible with -the POSIX@footnote{The 2008 POSIX standard is online at +the POSIX@footnote{The 2008 POSIX standard is accessable online at @url{http://www.opengroup.org/onlinepubs/9699919799/}.} specification of the @command{awk} language and with the Unix version of @command{awk} maintained @@ -1171,6 +1170,12 @@ Sort data @item Perform simple network communications + +@item +Profile and debug @command{awk} programs. + +@item +Extend the language with functions written in C or C++. @end itemize This @value{DOCUMENT} teaches you about the @command{awk} language and @@ -1186,12 +1191,18 @@ Implementations of the @command{awk} language are available for many different computing environments. This @value{DOCUMENT}, while describing the @command{awk} language in general, also describes the particular implementation of @command{awk} called @command{gawk} (which stands for -``GNU awk''). @command{gawk} runs on a broad range of Unix systems, +``GNU @command{awk}''). @command{gawk} runs on a broad range of Unix systems, ranging from Intel@registeredsymbol{}-architecture PC-based computers -up through large-scale systems, -such as Crays. @command{gawk} has also been ported to Mac OS X, -Microsoft Windows (all versions) and OS/2 PCs, -and VMS. +up through large-scale systems. +@command{gawk} has also been ported to Mac OS X, +Microsoft Windows +@ifset FOR_PRINT +(all versions) and OS/2 PCs, +@end ifset +@ifclear FOR_PRINT +(all versions), +@end ifclear +and OpenVMS. (Some other, obsolete systems to which @command{gawk} was once ported are no longer supported and the code for those systems has been removed.) @@ -1312,26 +1323,26 @@ The language described in this @value{DOCUMENT} is often referred to as ``new @command{awk}'' (@command{nawk}). @cindex @command{awk}, versions of -Because of this, there are systems with multiple -versions of @command{awk}. -Some systems have an @command{awk} utility that implements the -original version of the @command{awk} language and a @command{nawk} utility -for the new version. -Others have an @command{oawk} version for the ``old @command{awk}'' -language and plain @command{awk} for the new one. Still others only -have one version, which is usually the new one.@footnote{Often, these systems -use @command{gawk} for their @command{awk} implementation!} - @cindex @command{nawk} utility @cindex @command{oawk} utility -All in all, this makes it difficult for you to know which version of -@command{awk} you should run when writing your programs. The best advice -we can give here is to check your local documentation. Look for @command{awk}, -@command{oawk}, and @command{nawk}, as well as for @command{gawk}. -It is likely that you already -have some version of new @command{awk} on your system, which is what -you should use when running your programs. (Of course, if you're reading -this @value{DOCUMENT}, chances are good that you have @command{gawk}!) +For some time after new @command{awk} was introduced, there were +systems with multiple versions of @command{awk}. Some systems had +an @command{awk} utility that implemented the original version of the +@command{awk} language and a @command{nawk} utility for the new version. +Others had an @command{oawk} version for the ``old @command{awk}'' +language and plain @command{awk} for the new one. Still others only +had one version, which is usually the new one. + +Today, only Solaris systems still use an old @command{awk} for the +default @command{awk} utility. (A more modern @command{awk} lives in +@file{/usr/xpg6/bin} on these systems.) All other modern systems use +some version of new @command{awk}.@footnote{Many of these systems use +@command{gawk} for their @command{awk} implementation!} + +It is likely that you already have some version of new @command{awk} on +your system, which is what you should use when running your programs. +(Of course, if you're reading this @value{DOCUMENT}, chances are good +that you have @command{gawk}!) Throughout this @value{DOCUMENT}, whenever we refer to a language feature that should be available in any complete implementation of POSIX @command{awk}, @@ -1493,6 +1504,32 @@ non-POSIX systems. It also describes how to report bugs in @command{gawk} and where to get other freely available @command{awk} implementations. +@ifset FOR_PRINT +To save space, we have omitted some of the appendices from this +printed edition. You may find them online, as follows: + +@uref{http://www.gnu.org/software/gawk/manual/html_node/Notes.html} +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. + +@uref{http://www.gnu.org/software/gawk/manual/html_node/Basic-Concepts.html} +provides some very cursory background material for those who +are completely unfamiliar with computer programming. + +@uref{http://www.gnu.org/software/gawk/manual/html_node/Glossary.html, +The Glossary} +defines most, if not all, the significant terms used +throughout the book. If you find terms that you aren't familiar with, +try looking them up here. + +@uref{http://www.gnu.org/software/gawk/manual/html_node/Copying.html} and +@uref{http://www.gnu.org/software/gawk/manual/html_node/GNU-Free-Documentation-License.html} +present the licenses that cover the @command{gawk} source code +and this @value{DOCUMENT}, respectively. +@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}, @@ -1510,6 +1547,7 @@ try looking them up here. @ref{GNU Free Documentation License}, present the licenses that cover the @command{gawk} source code and this @value{DOCUMENT}, respectively. +@end ifclear @node Conventions @unnumberedsec Typographical Conventions @@ -1585,9 +1623,8 @@ the picture of a flashlight in the margin, as shown here. @end ifnottex They also appear in the index under the heading ``dark corner.'' -As noted by the opening quote, though, any -coverage of dark corners -is, by definition, incomplete. +As noted by the opening quote, though, any coverage of dark corners is, +by definition, incomplete. Extensions to the standard @command{awk} language that are supported by more than one @command{awk} implementation are marked @@ -1727,6 +1764,11 @@ the FSF published several preliminary versions (numbered 0.@var{x}). 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 +SSC published two editions of the @value{DOCUMENT} under the +title @cite{Effective awk Programming}, and in O'Reilly published +the edition in 2001. +@end ifset This edition maintains the basic structure of the previous editions. For Edition 4.0, the content has been thoroughly reviewed @@ -1738,13 +1780,12 @@ For edition @value{EDITION}, the content has been reorganized into parts, and the major new additions are @ref{Arbitrary Precision Arithmetic}, and @ref{Dynamic Extensions}. -@cite{@value{TITLE}} will undoubtedly continue to evolve. -An electronic version -comes with the @command{gawk} distribution from the FSF. -If you find an error in this @value{DOCUMENT}, please report it! -@xref{Bugs}, for information on submitting -problem reports electronically. +This @value{DOCUMENT} will undoubtedly continue to evolve. An electronic +version comes with the @command{gawk} distribution from the FSF. If you +find an error in this @value{DOCUMENT}, please report it! @xref{Bugs}, +for information on submitting problem reports electronically. +@ifclear FOR_PRINT @node How To Contribute @unnumberedsec How to Contribute @@ -1761,7 +1802,7 @@ However, I found that I could not dedicate enough time to managing contributed code: the archive did not grow and the domain went unused for several years. -Fortunately, late in 2008, a volunteer took on the task of setting up +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 nice job. @@ -1770,11 +1811,15 @@ 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. +As of this writing, this website is in search of a maintainer; please +contact me if you are interested. + @ignore Other links: http://www.reddit.com/r/linux/comments/dtect/composing_music_in_awk/ @end ignore +@end ifclear @node Acknowledgments @unnumberedsec Acknowledgments @@ -1936,7 +1981,7 @@ take advantage of those opportunities. Arnold Robbins @* Nof Ayalon @* ISRAEL @* -May, 2013 +May, 2014 @iftex @part Part I:@* The @command{awk} Language @@ -1944,11 +1989,11 @@ May, 2013 @ignore @ifdocbook -@part Part I:@* The @command{awk} Language - -Part I describes the @command{awk} language and @command{gawk} program in detail. -It starts with the basics, and continues through all of the features of @command{awk} -and @command{gawk}. It contains the following chapters: +Part I describes the @command{awk} language and @command{gawk} program +in detail. It starts with the basics, and continues through all of +the features of @command{awk}. Included also are many, but not all, +of the features of @command{gawk}. This part contains the +following chapters: @itemize @bullet @item @@ -2071,7 +2116,7 @@ variations of each. @menu * One-shot:: Running a short throwaway @command{awk} program. -* Read Terminal:: Using no input files (input from terminal +* Read Terminal:: Using no input files (input from the keyboard instead). * Long:: Putting permanent @command{awk} programs in files. @@ -2135,10 +2180,15 @@ awk '@var{program}' @noindent @command{awk} applies the @var{program} to the @dfn{standard input}, -which usually means whatever you type on the terminal. This continues +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.) +@end ifset +@ifclear FOR_PRINT (On other operating systems, the end-of-file character may be different. For example, on OS/2, it is @kbd{Ctrl-z}.) +@end ifclear @cindex files, input, See input files @cindex input files, running @command{awk} without @@ -3444,7 +3494,7 @@ 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 terminal. +By default, the debugger reads commands interactively from the keyboard. The optional @var{file} argument allows you to specify a file with a list of commands for the debugger to execute non-interactively. No space is allowed between the @option{-D} and @var{file}, if @@ -3751,7 +3801,7 @@ of having to be included into each individual program. function names must be unique.) With standard @command{awk}, library functions can still be used, even -if the program is entered at the terminal, +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 @@ -7455,7 +7505,7 @@ then @command{gawk} sets @code{RT} to the null string. @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 terminal, sometimes +input stream---either the standard input (usually your keyboard, sometimes the output from another program) or from the files specified on the command line. The @command{awk} language has a special built-in command called @code{getline} that @@ -8017,7 +8067,7 @@ Note: for each variant, @command{gawk} sets the @code{RT} built-in variable. @section Reading Input With A Timeout @cindex timeout, reading input -You may specify a timeout in milliseconds for reading input from a terminal, +You may specify a timeout in milliseconds for reading input from the keyboard, 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: @@ -8040,8 +8090,8 @@ else if (ERRNO != "") print ERRNO @end example -Here is how to read interactively from the terminal@footnote{This assumes -that standard input is the keyboard} without waiting +Here is how to read interactively from the user@footnote{This assumes +that standard input is the keyboard.} without waiting for more than five seconds: @example @@ -8056,7 +8106,7 @@ and set the @code{ERRNO} variable to an appropriate string value. A negative or zero value for the timeout is the same as specifying no timeout at all. -A timeout can also be set for reading from the terminal in the implicit +A timeout can also be set for reading from the keyboard in the implicit loop that reads input records and matches them against patterns, like so: @@ -29251,7 +29301,7 @@ The easiest way to find out is to look at the output of the following command: @example -$ @kbd{./gawk --version} +$ @kbd{gawk --version} @print{} GNU Awk 4.1.1, API: 1.1 (GNU MPFR 3.1.0-p3, GNU MP 5.0.2) @print{} Copyright (C) 1989, 1991-2014 Free Software Foundation. @dots{} @@ -35540,7 +35590,7 @@ Files needed for building @command{gawk} under MS-Windows and OS/2 (@pxref{PC Installation}, for details). @item vms/* -Files needed for building @command{gawk} under VMS +Files needed for building @command{gawk} under Vax/VMS and OpenVMS (@pxref{VMS Installation}, for details). @item test/* @@ -36122,7 +36172,7 @@ been ported to MS-Windows that expect @command{gawk} to do automatic translation of @code{"\r\n"}, since it won't. Caveat Emptor! @node VMS Installation -@appendixsubsec How to Compile and Install @command{gawk} on VMS +@appendixsubsec How to Compile and Install @command{gawk} on Vax/VMS and OpenVMS @c based on material from Pat Rankin <rankin@eql.caltech.edu> @c now rankin@pactechdata.com |