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diff --git a/doc/gawk.info b/doc/gawk.info index 468b5f72..da69dec9 100644 --- a/doc/gawk.info +++ b/doc/gawk.info @@ -29589,6 +29589,21 @@ ANSI C++ programming languages. These standards often become international standards as well. See also "ISO." +Argument + An argument can be two different things. It can be an option or a + file name passed to a command while invoking it from the command + line, or it can be something passed to a "function" inside a + program, e.g. inside `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 `awk' scalars are passed by value, and + arrays are passed by reference. See "Pass By Value/Reference." + Array A grouping of multiple values under the same name. Most languages just provide sequential arrays. `awk' provides associative arrays. @@ -29624,6 +29639,26 @@ Bash The GNU version of the standard shell (the Bourne-Again SHell). See also "Bourne Shell." +Binary + Base-two notation, where the digits are `0'-`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 "bit". So, for example, the base-two number `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. *Note Nondecimal-numbers::. + Bit Short for "Binary Digit." All values in computer memory ultimately reduce to binary digits: values that are either zero or @@ -29652,6 +29687,19 @@ Braces The characters `{' and `}'. Braces are used in `awk' for delimiting actions, compound statements, and function bodies. +Bracket Expression + Inside a "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 `[abc]', a range of characters, + like `[A-Z]', or a name, delimited by `:', that designates a known + set of characters, like `[:digit:]'. The form of bracket expression + enclosed between `:' 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." + Built-in Function The `awk' language provides built-in functions that perform various numerical, I/O-related, and string computations. Examples are @@ -29679,9 +29727,25 @@ C In general, `gawk' attempts to be as similar to the 1990 version of ISO C as makes sense. +C Shell + The C Shell (`csh' or its improved version, `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." + C++ A popular object-oriented programming language derived from C. +Character Class + See "Bracket Expression." + +Character List + See "Bracket Expression." + Character Set The set of numeric codes used by a computer system to represent the characters (letters, numbers, punctuation, etc.) of a particular @@ -29709,10 +29773,21 @@ Compiler machine-executable object code. The object code is then executed directly by the computer. See also "Interpreter." +Complemented Bracket Expression + The negation of a "bracket expression". All that is _not_ + described by a given bracket expression. The symbol `^' precedes + the negated bracket expression. E.g.: `[[^:digit:]' designates + whatever character is not a digit. `[^bad]' designates whatever + character is not one of the letters `b', `a', or `d'. See + "Bracket Expression." + Compound Statement A series of `awk' statements, enclosed in curly braces. Compound statements may be nested. (*Note Statements::.) +Computed Regexps + See "Dynamic Regular Expressions." + Concatenation Concatenating two strings means sticking them together, one after another, producing a new string. For example, the string `foo' @@ -29726,6 +29801,12 @@ Conditional Expression otherwise the value is EXPR3. In either case, only one of EXPR2 and EXPR3 is evaluated. (*Note Conditional Exp::.) +Control Statement + A control statement is an instruction to perform a given operation + or a set of operations inside an `awk' program, if a given + condition is true. Control statements are: `if', `for', `while', + and `do' (*note Statements::). + Cookie A peculiar goodie, token, saying or remembrance produced by or presented to a program. (With thanks to Professor Doug McIlroy.) @@ -29832,6 +29913,12 @@ Format are controlled by the format strings contained in the predefined variables `CONVFMT' and `OFMT'. (*Note Control Letters::.) +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. + Free Documentation License This document describes the terms under which this Info file is published and may be copied. (*Note GNU Free Documentation @@ -29847,9 +29934,16 @@ FSF See "Free Software Foundation." Function - A specialized group of statements used to encapsulate general or - program-specific tasks. `awk' has a number of built-in functions, - and also allows you to define your own. (*Note Functions::.) + A part of an `awk' program that can be invoked from every point of + the program, to perform a task. `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. *Note Functions::. In `gawk' it is also possible to + have functions shared among different programs, and included where + required using the `@include' directive (*note Include Files::). + In `gawk' the name of the function that should be invoked can be + generated at run time, i.e., dynamically. The `gawk' extension + API provides constructor functions (*note Constructor Functions::). `gawk' The GNU implementation of `awk'. @@ -29945,6 +30039,12 @@ Keyword `else', `exit', `for...in', `for', `function', `func', `if', `next', `nextfile', `switch', and `while'. +Korn Shell + The Korn Shell (`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." + Lesser General Public License This document describes the terms under which binary library archives or shared objects, and their source code may be @@ -29982,6 +30082,13 @@ Metacharacters Instead, they denote regular expression operations, such as repetition, grouping, or alternation. +Nesting + Nesting is where information is organized in layers, or where + objects contain other similar objects. In `gawk' the `@include' + directive can be nested. The "natural" nesting of arithmetic and + logical operations can be changed using parentheses (*note + Precedence::). + No-op An operation that does nothing. @@ -30001,6 +30108,11 @@ Octal are written in C using a leading `0', to indicate their base. Thus, `013' is 11 ((1 x 8) + 3). *Note Nondecimal-numbers::. +Output Record + A single chunk of data that is written out by `awk'. Usually, an + `awk' output record consists of one or more lines of text. *Note + Records::. + Pattern Patterns tell `awk' which input records are interesting to which rules. @@ -30016,6 +30128,9 @@ PEBKAC computer usage problems. (Problem Exists Between Keyboard And Chair.) +Plug-in + See "Extensions." + POSIX The name for a series of standards that specify a Portable Operating System interface. The "IX" denotes the Unix heritage of @@ -30039,6 +30154,9 @@ Range (of input lines) can specify ranges of input lines for `awk' to process or it can specify single lines. (*Note Pattern Overview::.) +Record + See "Input record" and "Output record." + Recursion When a function calls itself, either directly or indirectly. If this is clear, stop, and proceed to the next entry. Otherwise, @@ -30055,6 +30173,16 @@ Redirection using the `>', `>>', `|', and `|&' operators. (*Note Getline::, and *note Redirection::.) +Reference Counts + An internal mechanism in `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. + Regexp See "Regular Expression." @@ -30073,6 +30201,15 @@ Regular Expression Constant when you write the `awk' program and cannot be changed during its execution. (*Note Regexp Usage::.) +Regular Expression Operators + See "Metacharacters." + +Rounding + Rounding the result of an arithmetic operation can be tricky. + More than one way of rounding exists, and in `gawk' it is possible + to choose which method should be used in a program. *Note Setting + the rounding mode::. + Rule A segment of an `awk' program that specifies how to process single input records. A rule consists of a "pattern" and an "action". @@ -30134,6 +30271,11 @@ Special File handed directly to the underlying operating system--for example, `/dev/stderr'. (*Note Special Files::.) +Statement + An expression inside an `awk' program in the action part of a + pattern-action rule, or inside an `awk' function. A statement can + be a variable assignment, an array operation, a loop, etc. + 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 @@ -30176,10 +30318,15 @@ UTC reference time for day and date calculations. See also "Epoch" and "GMT." +Variable + A name for a value. In `awk', variables may be either scalars or + arrays. + Whitespace A sequence of space, TAB, or newline characters occurring inside an input record or a string. + File: gawk.info, Node: Copying, Next: GNU Free Documentation License, Prev: Glossary, Up: Top @@ -31775,7 +31922,7 @@ Index (line 18) * artificial intelligence, gawk and: Distribution contents. (line 52) -* ASCII <1>: Glossary. (line 133) +* ASCII <1>: Glossary. (line 197) * ASCII: Ordinal Functions. (line 45) * asort <1>: Array Sorting Functions. (line 6) @@ -31947,7 +32094,7 @@ Index * BEGINFILE pattern, Boolean patterns and: Expression Patterns. (line 69) * beginfile() user-defined function: Filetrans Function. (line 61) -* Bentley, Jon: Glossary. (line 143) +* Bentley, Jon: Glossary. (line 207) * Benzinger, Michael: Contributors. (line 97) * Berry, Karl <1>: Ranges and Locales. (line 74) * Berry, Karl: Acknowledgments. (line 33) @@ -32029,7 +32176,7 @@ Index * Brink, Jeroen: DOS Quoting. (line 10) * Broder, Alan J.: Contributors. (line 88) * Brown, Martin: Contributors. (line 82) -* BSD-based operating systems: Glossary. (line 611) +* BSD-based operating systems: Glossary. (line 753) * bt debugger command (alias for backtrace): Execution Stack. (line 13) * Buening, Andreas <1>: Bugs. (line 70) * Buening, Andreas <2>: Contributors. (line 92) @@ -32071,7 +32218,7 @@ Index (line 56) * character lists in regular expression: Bracket Expressions. (line 6) * character lists, See bracket expressions: Regexp Operators. (line 56) -* character sets (machine character encodings) <1>: Glossary. (line 133) +* character sets (machine character encodings) <1>: Glossary. (line 197) * character sets (machine character encodings): Ordinal Functions. (line 45) * character sets, See Also bracket expressions: Regexp Operators. @@ -32082,7 +32229,7 @@ Index * Chassell, Robert J.: Acknowledgments. (line 33) * chdir() extension function: Extension Sample File Functions. (line 12) -* chem utility: Glossary. (line 143) +* chem utility: Glossary. (line 207) * chr() extension function: Extension Sample Ord. (line 15) * chr() user-defined function: Ordinal Functions. (line 16) @@ -32159,7 +32306,7 @@ Index * compatibility mode (gawk), octal numbers: Nondecimal-numbers. (line 60) * compatibility mode (gawk), specifying: Options. (line 81) -* compiled programs <1>: Glossary. (line 155) +* compiled programs <1>: Glossary. (line 219) * compiled programs: Basic High Level. (line 15) * compiling gawk for Cygwin: Cygwin. (line 6) * compiling gawk for MS-DOS and MS-Windows: PC Compiling. (line 13) @@ -32205,7 +32352,7 @@ Index * CONVFMT variable: Strings And Numbers. (line 29) * CONVFMT variable, and array subscripts: Numeric Array Subscripts. (line 6) -* cookie: Glossary. (line 177) +* cookie: Glossary. (line 258) * coprocesses <1>: Two-way I/O. (line 25) * coprocesses: Redirection. (line 96) * coprocesses, closing: Close Files And Pipes. @@ -32229,7 +32376,7 @@ Index * cut.awk program: Cut Program. (line 45) * d debugger command (alias for delete): Breakpoint Control. (line 64) * d.c., See dark corner: Conventions. (line 42) -* dark corner <1>: Glossary. (line 188) +* dark corner <1>: Glossary. (line 269) * dark corner: Conventions. (line 42) * dark corner, "0" is actually true: Truth Values. (line 24) * dark corner, /= operator vs. /=.../ regexp constant: Assignment Ops. @@ -32576,7 +32723,7 @@ Index * environment variables used by gawk: Environment Variables. (line 6) * environment variables, in ENVIRON array: Auto-set. (line 60) -* epoch, definition of: Glossary. (line 234) +* epoch, definition of: Glossary. (line 315) * equals sign (=), = operator: Assignment Ops. (line 6) * equals sign (=), == operator <1>: Precedence. (line 65) * equals sign (=), == operator: Comparison Operators. @@ -32822,10 +32969,10 @@ Index * frame debugger command: Execution Stack. (line 27) * Free Documentation License (FDL): GNU Free Documentation License. (line 7) -* Free Software Foundation (FSF) <1>: Glossary. (line 288) +* Free Software Foundation (FSF) <1>: Glossary. (line 375) * Free Software Foundation (FSF) <2>: Getting. (line 10) * Free Software Foundation (FSF): Manual History. (line 6) -* FreeBSD: Glossary. (line 611) +* FreeBSD: Glossary. (line 753) * FS variable <1>: User-modified. (line 50) * FS variable: Field Separators. (line 15) * FS variable, --field-separator option and: Options. (line 21) @@ -32839,7 +32986,7 @@ Index * FS, containing ^: Regexp Field Splitting. (line 59) * FS, in multiline records: Multiple Line. (line 41) -* FSF (Free Software Foundation) <1>: Glossary. (line 288) +* FSF (Free Software Foundation) <1>: Glossary. (line 375) * FSF (Free Software Foundation) <2>: Getting. (line 10) * FSF (Free Software Foundation): Manual History. (line 6) * fts() extension function: Extension Sample File Functions. @@ -32992,7 +33139,7 @@ Index * gawkpath_append shell function: Shell Startup Files. (line 19) * gawkpath_default shell function: Shell Startup Files. (line 12) * gawkpath_prepend shell function: Shell Startup Files. (line 15) -* General Public License (GPL): Glossary. (line 305) +* General Public License (GPL): Glossary. (line 399) * General Public License, See GPL: Manual History. (line 11) * generate time values: Time Functions. (line 25) * gensub <1>: String Functions. (line 90) @@ -33050,18 +33197,18 @@ Index * GNU awk, See gawk: Preface. (line 51) * GNU Free Documentation License: GNU Free Documentation License. (line 7) -* GNU General Public License: Glossary. (line 305) -* GNU Lesser General Public License: Glossary. (line 396) +* GNU General Public License: Glossary. (line 399) +* GNU Lesser General Public License: Glossary. (line 496) * GNU long options <1>: Options. (line 6) * GNU long options: Command Line. (line 13) * GNU long options, printing list of: Options. (line 154) -* GNU Project <1>: Glossary. (line 314) +* GNU Project <1>: Glossary. (line 408) * GNU Project: Manual History. (line 11) -* GNU/Linux <1>: Glossary. (line 611) +* GNU/Linux <1>: Glossary. (line 753) * GNU/Linux <2>: I18N Example. (line 55) * GNU/Linux: Manual History. (line 28) * Gordon, Assaf: Contributors. (line 105) -* GPL (General Public License) <1>: Glossary. (line 305) +* GPL (General Public License) <1>: Glossary. (line 399) * GPL (General Public License): Manual History. (line 11) * GPL (General Public License), printing: Options. (line 88) * grcat program: Group Functions. (line 16) @@ -33193,20 +33340,20 @@ Index * internationalization, localization, portability and: I18N Portability. (line 6) * internationalizing a program: Explaining gettext. (line 6) -* interpreted programs <1>: Glossary. (line 356) +* interpreted programs <1>: Glossary. (line 450) * interpreted programs: Basic High Level. (line 15) * interval expressions, regexp operator: Regexp Operators. (line 116) * inventory-shipped file: Sample Data Files. (line 32) * invoke shell command: I/O Functions. (line 106) * isarray: Type Functions. (line 11) -* ISO: Glossary. (line 367) -* ISO 8859-1: Glossary. (line 133) -* ISO Latin-1: Glossary. (line 133) +* ISO: Glossary. (line 461) +* ISO 8859-1: Glossary. (line 197) +* ISO Latin-1: Glossary. (line 197) * Jacobs, Andrew: Passwd Functions. (line 90) * Jaegermann, Michal <1>: Contributors. (line 45) * Jaegermann, Michal: Acknowledgments. (line 60) * Java implementation of awk: Other Versions. (line 117) -* Java programming language: Glossary. (line 379) +* Java programming language: Glossary. (line 473) * jawk: Other Versions. (line 117) * Jedi knights: Undocumented. (line 6) * Johansen, Chris: Signature Program. (line 25) @@ -33215,7 +33362,7 @@ Index * Kahrs, Ju"rgen: Acknowledgments. (line 60) * Kasal, Stepan: Acknowledgments. (line 60) * Kenobi, Obi-Wan: Undocumented. (line 6) -* Kernighan, Brian <1>: Glossary. (line 143) +* Kernighan, Brian <1>: Glossary. (line 207) * Kernighan, Brian <2>: Basic Data Typing. (line 54) * Kernighan, Brian <3>: Other Versions. (line 13) * Kernighan, Brian <4>: Contributors. (line 11) @@ -33256,8 +33403,8 @@ Index * length: String Functions. (line 171) * length of input record: String Functions. (line 178) * length of string: String Functions. (line 171) -* Lesser General Public License (LGPL): Glossary. (line 396) -* LGPL (Lesser General Public License): Glossary. (line 396) +* Lesser General Public License (LGPL): Glossary. (line 496) +* LGPL (Lesser General Public License): Glossary. (line 496) * libmawk: Other Versions. (line 125) * libraries of awk functions: Library Functions. (line 6) * libraries of awk functions, assertions: Assert Function. (line 6) @@ -33302,7 +33449,7 @@ Index * lint checking, undefined functions: Pass By Value/Reference. (line 85) * LINT variable: User-modified. (line 88) -* Linux <1>: Glossary. (line 611) +* Linux <1>: Glossary. (line 753) * Linux <2>: I18N Example. (line 55) * Linux: Manual History. (line 28) * list all global variables, in debugger: Debugger Info. (line 48) @@ -33364,7 +33511,7 @@ Index * mawk utility <4>: Getline/Pipe. (line 62) * mawk utility: Escape Sequences. (line 120) * maximum precision supported by MPFR library: Auto-set. (line 235) -* McIlroy, Doug: Glossary. (line 177) +* McIlroy, Doug: Glossary. (line 258) * McPhee, Patrick: Contributors. (line 100) * message object files: Explaining gettext. (line 42) * message object files, converting from portable object files: I18N Example. @@ -33392,7 +33539,7 @@ Index * names, functions: Definition Syntax. (line 23) * namespace issues: Library Names. (line 6) * namespace issues, functions: Definition Syntax. (line 23) -* NetBSD: Glossary. (line 611) +* NetBSD: Glossary. (line 753) * networks, programming: TCP/IP Networking. (line 6) * networks, support for: Special Network. (line 6) * newlines <1>: Boolean Ops. (line 69) @@ -33480,7 +33627,7 @@ Index * OFS variable <1>: User-modified. (line 113) * OFS variable <2>: Output Separators. (line 6) * OFS variable: Changing Fields. (line 64) -* OpenBSD: Glossary. (line 611) +* OpenBSD: Glossary. (line 753) * OpenSolaris: Other Versions. (line 100) * operating systems, BSD-based: Manual History. (line 28) * operating systems, PC, gawk on: PC Using. (line 6) @@ -33753,7 +33900,7 @@ Index * programming languages, Ada: Glossary. (line 11) * programming languages, data-driven vs. procedural: Getting Started. (line 12) -* programming languages, Java: Glossary. (line 379) +* programming languages, Java: Glossary. (line 473) * programming, basic steps: Basic High Level. (line 20) * programming, concepts: Basic Concepts. (line 6) * pwcat program: Passwd Functions. (line 23) @@ -34115,7 +34262,7 @@ Index * square root: Numeric Functions. (line 92) * srand: Numeric Functions. (line 96) * stack frame: Debugging Terms. (line 10) -* Stallman, Richard <1>: Glossary. (line 288) +* Stallman, Richard <1>: Glossary. (line 375) * Stallman, Richard <2>: Contributors. (line 23) * Stallman, Richard <3>: Acknowledgments. (line 18) * Stallman, Richard: Manual History. (line 6) @@ -34300,14 +34447,14 @@ Index * undisplay debugger command: Viewing And Changing Data. (line 80) * undocumented features: Undocumented. (line 6) -* Unicode <1>: Glossary. (line 133) +* Unicode <1>: Glossary. (line 197) * Unicode <2>: Ranges and Locales. (line 61) * Unicode: Ordinal Functions. (line 45) * uninitialized variables, as array subscripts: Uninitialized Subscripts. (line 6) * uniq utility: Uniq Program. (line 6) * uniq.awk program: Uniq Program. (line 65) -* Unix: Glossary. (line 611) +* Unix: Glossary. (line 753) * Unix awk, backslashes in escape sequences: Escape Sequences. (line 120) * Unix awk, close() function and: Close Files And Pipes. @@ -35008,8 +35155,8 @@ Ref: figure-process-flow1183022 Ref: Basic High Level-Footnote-11186251 Node: Basic Data Typing1186436 Node: Glossary1189764 -Node: Copying1214922 -Node: GNU Free Documentation License1252478 -Node: Index1277614 +Node: Copying1221710 +Node: GNU Free Documentation License1259266 +Node: Index1284402 End Tag Table |