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diff --git a/man3/regex.3 b/man3/regex.3 deleted file mode 100644 index fb641ef..0000000 --- a/man3/regex.3 +++ /dev/null @@ -1,411 +0,0 @@ -'\" t -.\" Copyright (C), 1995, Graeme W. Wilford. (Wilf.) -.\" Copyright 2023, Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz> -.\" Copyright 2023, Alejandro Colomar <alx@kernel.org> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Wed Jun 14 16:10:28 BST 1995 Wilf. (G.Wilford@ee.surrey.ac.uk) -.\" Tiny change in formatting - aeb, 950812 -.\" Modified 8 May 1998 by Joseph S. Myers (jsm28@cam.ac.uk) -.\" -.\" show the synopsis section nicely -.TH regex 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -regcomp, regexec, regerror, regfree \- POSIX regex functions -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <regex.h> -.P -.BI "int regcomp(regex_t *restrict " preg ", const char *restrict " regex , -.BI " int " cflags ); -.BI "int regexec(const regex_t *restrict " preg \ -", const char *restrict " string , -.BI " size_t " nmatch ", \ -regmatch_t " pmatch "[_Nullable restrict ." nmatch ], -.BI " int " eflags ); -.P -.BI "size_t regerror(int " errcode ", const regex_t *_Nullable restrict " preg , -.BI " char " errbuf "[_Nullable restrict ." errbuf_size ], -.BI " size_t " errbuf_size ); -.BI "void regfree(regex_t *" preg ); -.P -.B typedef struct { -.B " size_t re_nsub;" -.B } regex_t; -.P -.B typedef struct { -.B " regoff_t rm_so;" -.B " regoff_t rm_eo;" -.B } regmatch_t; -.P -.BR typedef " /* ... */ " regoff_t; -.fi -.SH DESCRIPTION -.SS Compilation -.BR regcomp () -is used to compile a regular expression into a form that is suitable -for subsequent -.BR regexec () -searches. -.P -On success, the pattern buffer at -.I *preg -is initialized. -.I regex -is a null-terminated string. -The locale must be the same when running -.BR regexec (). -.P -After -.BR regcomp () -succeeds, -.I preg->re_nsub -holds the number of subexpressions in -.IR regex . -Thus, a value of -.I preg->re_nsub -+ 1 -passed as -.I nmatch -to -.BR regexec () -is sufficient to capture all matches. -.P -.I cflags -is the -bitwise OR -of zero or more of the following: -.TP -.B REG_EXTENDED -Use -POSIX -Extended Regular Expression syntax when interpreting -.IR regex . -If not set, -POSIX -Basic Regular Expression syntax is used. -.TP -.B REG_ICASE -Do not differentiate case. -Subsequent -.BR regexec () -searches using this pattern buffer will be case insensitive. -.TP -.B REG_NOSUB -Report only overall success. -.BR regexec () -will use only -.I pmatch -for -.BR REG_STARTEND , -ignoring -.IR nmatch . -.TP -.B REG_NEWLINE -Match-any-character operators don't match a newline. -.IP -A nonmatching list -.RB ( [\[ha]...\&] ) -not containing a newline does not match a newline. -.IP -Match-beginning-of-line operator -.RB ( \[ha] ) -matches the empty string immediately after a newline, regardless of -whether -.IR eflags , -the execution flags of -.BR regexec (), -contains -.BR REG_NOTBOL . -.IP -Match-end-of-line operator -.RB ( $ ) -matches the empty string immediately before a newline, regardless of -whether -.I eflags -contains -.BR REG_NOTEOL . -.SS Matching -.BR regexec () -is used to match a null-terminated string -against the compiled pattern buffer in -.IR *preg , -which must have been initialised with -.BR regexec (). -.I eflags -is the -bitwise OR -of zero or more of the following flags: -.TP -.B REG_NOTBOL -The match-beginning-of-line operator always fails to match (but see the -compilation flag -.B REG_NEWLINE -above). -This flag may be used when different portions of a string are passed to -.BR regexec () -and the beginning of the string should not be interpreted as the -beginning of the line. -.TP -.B REG_NOTEOL -The match-end-of-line operator always fails to match (but see the -compilation flag -.B REG_NEWLINE -above). -.TP -.B REG_STARTEND -Match -.RI [ "string + pmatch[0].rm_so" , " string + pmatch[0].rm_eo" ) -instead of -.RI [ string , " string + strlen(string)" ). -This allows matching embedded NUL bytes -and avoids a -.BR strlen (3) -on known-length strings. -If any matches are returned -.RB ( REG_NOSUB -wasn't passed to -.BR regcomp (), -the match succeeded, and -.I nmatch -> 0), they overwrite -.I pmatch -as usual, and the match offsets remain relative to -.I string -(not -.IR "string + pmatch[0].rm_so" ). -This flag is a BSD extension, not present in POSIX. -.SS Match offsets -Unless -.B REG_NOSUB -was passed to -.BR regcomp (), -it is possible to -obtain the locations of matches within -.IR string : -.BR regexec () -fills -.I nmatch -elements of -.I pmatch -with results: -.I pmatch[0] -corresponds to the entire match, -.I pmatch[1] -to the first subexpression, etc. -If there were more matches than -.IR nmatch , -they are discarded; -if fewer, -unused elements of -.I pmatch -are filled with -.BR \-1 s. -.P -Each returned valid -.RB (non- \-1 ) -match corresponds to the range -.RI [ "string + rm_so" , " string + rm_eo" ). -.P -.I regoff_t -is a signed integer type -capable of storing the largest value that can be stored in either an -.I ptrdiff_t -type or a -.I ssize_t -type. -.SS Error reporting -.BR regerror () -is used to turn the error codes that can be returned by both -.BR regcomp () -and -.BR regexec () -into error message strings. -.P -If -.I preg -isn't a null pointer, -.I errcode -must be the latest error returned from an operation on -.IR preg . -.P -If -.I errbuf_size -isn't 0, up to -.I errbuf_size -bytes are copied to -.IR errbuf ; -the error string is always null-terminated, and truncated to fit. -.SS Freeing -.BR regfree () -deinitializes the pattern buffer at -.IR *preg , -freeing any associated memory; -.I *preg -must have been initialized via -.BR regcomp (). -.SH RETURN VALUE -.BR regcomp () -returns zero for a successful compilation or an error code for failure. -.P -.BR regexec () -returns zero for a successful match or -.B REG_NOMATCH -for failure. -.P -.BR regerror () -returns the size of the buffer required to hold the string. -.SH ERRORS -The following errors can be returned by -.BR regcomp (): -.TP -.B REG_BADBR -Invalid use of back reference operator. -.TP -.B REG_BADPAT -Invalid use of pattern operators such as group or list. -.TP -.B REG_BADRPT -Invalid use of repetition operators such as using \[aq]*\[aq] -as the first character. -.TP -.B REG_EBRACE -Un-matched brace interval operators. -.TP -.B REG_EBRACK -Un-matched bracket list operators. -.TP -.B REG_ECOLLATE -Invalid collating element. -.TP -.B REG_ECTYPE -Unknown character class name. -.TP -.B REG_EEND -Nonspecific error. -This is not defined by POSIX. -.TP -.B REG_EESCAPE -Trailing backslash. -.TP -.B REG_EPAREN -Un-matched parenthesis group operators. -.TP -.B REG_ERANGE -Invalid use of the range operator; for example, the ending point of the range -occurs prior to the starting point. -.TP -.B REG_ESIZE -Compiled regular expression requires a pattern buffer larger than 64\ kB. -This is not defined by POSIX. -.TP -.B REG_ESPACE -The regex routines ran out of memory. -.TP -.B REG_ESUBREG -Invalid back reference to a subexpression. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR regcomp (), -.BR regexec () -T} Thread safety MT-Safe locale -T{ -.na -.nh -.BR regerror () -T} Thread safety MT-Safe env -T{ -.na -.nh -.BR regfree () -T} Thread safety MT-Safe -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001. -.P -Prior to POSIX.1-2008, -.I regoff_t -was required to be -capable of storing the largest value that can be stored in either an -.I off_t -type or a -.I ssize_t -type. -.SH CAVEATS -.I re_nsub -is only required to be initialized if -.B REG_NOSUB -wasn't specified, but all known implementations initialize it regardless. -.\" glibc, musl, 4.4BSD, illumos -.P -Both -.I regex_t -and -.I regmatch_t -may (and do) have more members, in any order. -Always reference them by name. -.\" illumos has two more start/end pairs and the first one is of pointers -.SH EXAMPLES -.EX -#include <stdint.h> -#include <stdio.h> -#include <stdlib.h> -#include <regex.h> -\& -#define ARRAY_SIZE(arr) (sizeof((arr)) / sizeof((arr)[0])) -\& -static const char *const str = - "1) John Driverhacker;\en2) John Doe;\en3) John Foo;\en"; -static const char *const re = "John.*o"; -\& -int main(void) -{ - static const char *s = str; - regex_t regex; - regmatch_t pmatch[1]; - regoff_t off, len; -\& - if (regcomp(®ex, re, REG_NEWLINE)) - exit(EXIT_FAILURE); -\& - printf("String = \e"%s\e"\en", str); - printf("Matches:\en"); -\& - for (unsigned int i = 0; ; i++) { - if (regexec(®ex, s, ARRAY_SIZE(pmatch), pmatch, 0)) - break; -\& - off = pmatch[0].rm_so + (s \- str); - len = pmatch[0].rm_eo \- pmatch[0].rm_so; - printf("#%zu:\en", i); - printf("offset = %jd; length = %jd\en", (intmax_t) off, - (intmax_t) len); - printf("substring = \e"%.*s\e"\en", len, s + pmatch[0].rm_so); -\& - s += pmatch[0].rm_eo; - } -\& - exit(EXIT_SUCCESS); -} -.EE -.SH SEE ALSO -.BR grep (1), -.BR regex (7) -.P -The glibc manual section, -.I "Regular Expressions" |