diff options
Diffstat (limited to 'dist2/doc/html/pcre2posix.html')
| -rw-r--r-- | dist2/doc/html/pcre2posix.html | 152 |
1 files changed, 65 insertions, 87 deletions
diff --git a/dist2/doc/html/pcre2posix.html b/dist2/doc/html/pcre2posix.html index 20a2009b..1da24601 100644 --- a/dist2/doc/html/pcre2posix.html +++ b/dist2/doc/html/pcre2posix.html @@ -15,75 +15,51 @@ please consult the man page, in case the conversion went wrong. <ul> <li><a name="TOC1" href="#SEC1">SYNOPSIS</a> <li><a name="TOC2" href="#SEC2">DESCRIPTION</a> -<li><a name="TOC3" href="#SEC3">USING THE POSIX FUNCTIONS</a> -<li><a name="TOC4" href="#SEC4">COMPILING A PATTERN</a> -<li><a name="TOC5" href="#SEC5">MATCHING NEWLINE CHARACTERS</a> -<li><a name="TOC6" href="#SEC6">MATCHING A PATTERN</a> -<li><a name="TOC7" href="#SEC7">ERROR MESSAGES</a> -<li><a name="TOC8" href="#SEC8">MEMORY USAGE</a> -<li><a name="TOC9" href="#SEC9">AUTHOR</a> -<li><a name="TOC10" href="#SEC10">REVISION</a> +<li><a name="TOC3" href="#SEC3">COMPILING A PATTERN</a> +<li><a name="TOC4" href="#SEC4">MATCHING NEWLINE CHARACTERS</a> +<li><a name="TOC5" href="#SEC5">MATCHING A PATTERN</a> +<li><a name="TOC6" href="#SEC6">ERROR MESSAGES</a> +<li><a name="TOC7" href="#SEC7">MEMORY USAGE</a> +<li><a name="TOC8" href="#SEC8">AUTHOR</a> +<li><a name="TOC9" href="#SEC9">REVISION</a> </ul> <br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br> <P> <b>#include <pcre2posix.h></b> </P> <P> -<b>int pcre2_regcomp(regex_t *<i>preg</i>, const char *<i>pattern</i>,</b> +<b>int regcomp(regex_t *<i>preg</i>, const char *<i>pattern</i>,</b> <b> int <i>cflags</i>);</b> <br> <br> -<b>int pcre2_regexec(const regex_t *<i>preg</i>, const char *<i>string</i>,</b> +<b>int regexec(const regex_t *<i>preg</i>, const char *<i>string</i>,</b> <b> size_t <i>nmatch</i>, regmatch_t <i>pmatch</i>[], int <i>eflags</i>);</b> <br> <br> -<b>size_t pcre2_regerror(int <i>errcode</i>, const regex_t *<i>preg</i>,</b> +<b>size_t regerror(int <i>errcode</i>, const regex_t *<i>preg</i>,</b> <b> char *<i>errbuf</i>, size_t <i>errbuf_size</i>);</b> <br> <br> -<b>void pcre2_regfree(regex_t *<i>preg</i>);</b> +<b>void regfree(regex_t *<i>preg</i>);</b> </P> <br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br> <P> This set of functions provides a POSIX-style API for the PCRE2 regular -expression 8-bit library. There are no POSIX-style wrappers for PCRE2's 16-bit -and 32-bit libraries. See the +expression 8-bit library. See the <a href="pcre2api.html"><b>pcre2api</b></a> documentation for a description of PCRE2's native API, which contains much -additional functionality. +additional functionality. There are no POSIX-style wrappers for PCRE2's 16-bit +and 32-bit libraries. </P> <P> -The functions described here are wrapper functions that ultimately call the -PCRE2 native API. Their prototypes are defined in the <b>pcre2posix.h</b> header -file, and they all have unique names starting with <b>pcre2_</b>. However, the -<b>pcre2posix.h</b> header also contains macro definitions that convert the -standard POSIX names such <b>regcomp()</b> into <b>pcre2_regcomp()</b> etc. This -means that a program can use the usual POSIX names without running the risk of -accidentally linking with POSIX functions from a different library. +The functions described here are just wrapper functions that ultimately call +the PCRE2 native API. Their prototypes are defined in the <b>pcre2posix.h</b> +header file, and on Unix systems the library itself is called +<b>libpcre2-posix.a</b>, so can be accessed by adding <b>-lpcre2-posix</b> to the +command for linking an application that uses them. Because the POSIX functions +call the native ones, it is also necessary to add <b>-lpcre2-8</b>. </P> <P> -On Unix-like systems the PCRE2 POSIX library is called <b>libpcre2-posix</b>, so -can be accessed by adding <b>-lpcre2-posix</b> to the command for linking an -application. Because the POSIX functions call the native ones, it is also -necessary to add <b>-lpcre2-8</b>. -</P> -<P> -Although they are not defined as protypes in <b>pcre2posix.h</b>, the library -does contain functions with the POSIX names <b>regcomp()</b> etc. These simply -pass their arguments to the PCRE2 functions. These functions are provided for -backwards compatibility with earlier versions of PCRE2, so that existing -programs do not have to be recompiled. -</P> -<P> -Calling the header file <b>pcre2posix.h</b> avoids any conflict with other POSIX -libraries. It can, of course, be renamed or aliased as <b>regex.h</b>, which is -the "correct" name, if there is no clash. It provides two structure types, -<i>regex_t</i> for compiled internal forms, and <i>regmatch_t</i> for returning -captured substrings. It also defines some constants whose names start with -"REG_"; these are used for setting options and identifying error codes. -</P> -<br><a name="SEC3" href="#TOC1">USING THE POSIX FUNCTIONS</a><br> -<P> Those POSIX option bits that can reasonably be mapped to PCRE2 native options have been implemented. In addition, the option REG_EXTENDED is defined with the value zero. This has no effect, but since programs that are written to the @@ -104,13 +80,17 @@ POSIX definition; it is not fully POSIX-compatible, and in multi-unit encoding domains it is probably even less compatible. </P> <P> -The descriptions below use the actual names of the functions, but, as described -above, the standard POSIX names (without the <b>pcre2_</b> prefix) may also be -used. +The header for these functions is supplied as <b>pcre2posix.h</b> to avoid any +potential clash with other POSIX libraries. It can, of course, be renamed or +aliased as <b>regex.h</b>, which is the "correct" name. It provides two +structure types, <i>regex_t</i> for compiled internal forms, and +<i>regmatch_t</i> for returning captured substrings. It also defines some +constants whose names start with "REG_"; these are used for setting options and +identifying error codes. </P> -<br><a name="SEC4" href="#TOC1">COMPILING A PATTERN</a><br> +<br><a name="SEC3" href="#TOC1">COMPILING A PATTERN</a><br> <P> -The function <b>pcre2_regcomp()</b> is called to compile a pattern into an +The function <b>regcomp()</b> is called to compile a pattern into an internal form. By default, the pattern is a C string terminated by a binary zero (but see REG_PEND below). The <i>preg</i> argument is a pointer to a <b>regex_t</b> structure that is used as a base for storing information about @@ -148,18 +128,18 @@ REG_UTF. Note that REG_NOSPEC is not part of the POSIX standard. <pre> REG_NOSUB </pre> -When a pattern that is compiled with this flag is passed to -<b>pcre2_regexec()</b> for matching, the <i>nmatch</i> and <i>pmatch</i> arguments -are ignored, and no captured strings are returned. Versions of the PCRE library -prior to 10.22 used to set the PCRE2_NO_AUTO_CAPTURE compile option, but this -no longer happens because it disables the use of backreferences. +When a pattern that is compiled with this flag is passed to <b>regexec()</b> for +matching, the <i>nmatch</i> and <i>pmatch</i> arguments are ignored, and no +captured strings are returned. Versions of the PCRE library prior to 10.22 used +to set the PCRE2_NO_AUTO_CAPTURE compile option, but this no longer happens +because it disables the use of backreferences. <pre> REG_PEND </pre> If this option is set, the <b>reg_endp</b> field in the <i>preg</i> structure (which has the type const char *) must be set to point to the character beyond -the end of the pattern before calling <b>pcre2_regcomp()</b>. The pattern itself -may now contain binary zeros, which are treated as data characters. Without +the end of the pattern before calling <b>regcomp()</b>. The pattern itself may +now contain binary zeros, which are treated as data characters. Without REG_PEND, a binary zero terminates the pattern and the <b>re_endp</b> field is ignored. This is a GNU extension to the POSIX standard and should be used with caution in software intended to be portable to other systems. @@ -194,19 +174,18 @@ newlines are matched by the dot metacharacter (they are not) or by a negative class such as [^a] (they are). </P> <P> -The yield of <b>pcre2_regcomp()</b> is zero on success, and non-zero otherwise. -The <i>preg</i> structure is filled in on success, and one other member of the +The yield of <b>regcomp()</b> is zero on success, and non-zero otherwise. The +<i>preg</i> structure is filled in on success, and one other member of the structure (as well as <i>re_endp</i>) is public: <i>re_nsub</i> contains the number of capturing subpatterns in the regular expression. Various error codes are defined in the header file. </P> <P> -NOTE: If the yield of <b>pcre2_regcomp()</b> is non-zero, you must not attempt -to use the contents of the <i>preg</i> structure. If, for example, you pass it -to <b>pcre2_regexec()</b>, the result is undefined and your program is likely to -crash. +NOTE: If the yield of <b>regcomp()</b> is non-zero, you must not attempt to +use the contents of the <i>preg</i> structure. If, for example, you pass it to +<b>regexec()</b>, the result is undefined and your program is likely to crash. </P> -<br><a name="SEC5" href="#TOC1">MATCHING NEWLINE CHARACTERS</a><br> +<br><a name="SEC4" href="#TOC1">MATCHING NEWLINE CHARACTERS</a><br> <P> This area is not simple, because POSIX and Perl take different views of things. It is not possible to get PCRE2 to obey POSIX semantics, but then PCRE2 was @@ -240,16 +219,16 @@ is no way to stop newline from matching [^a]. Default POSIX newline handling can be obtained by setting PCRE2_DOTALL and PCRE2_DOLLAR_ENDONLY when calling <b>pcre2_compile()</b> directly, but there is no way to make PCRE2 behave exactly as for the REG_NEWLINE action. When using -the POSIX API, passing REG_NEWLINE to PCRE2's <b>pcre2_regcomp()</b> function +the POSIX API, passing REG_NEWLINE to PCRE2's <b>regcomp()</b> function causes PCRE2_MULTILINE to be passed to <b>pcre2_compile()</b>, and REG_DOTALL passes PCRE2_DOTALL. There is no way to pass PCRE2_DOLLAR_ENDONLY. </P> -<br><a name="SEC6" href="#TOC1">MATCHING A PATTERN</a><br> +<br><a name="SEC5" href="#TOC1">MATCHING A PATTERN</a><br> <P> -The function <b>pcre2_regexec()</b> is called to match a compiled pattern -<i>preg</i> against a given <i>string</i>, which is by default terminated by a -zero byte (but see REG_STARTEND below), subject to the options in <i>eflags</i>. -These can be: +The function <b>regexec()</b> is called to match a compiled pattern <i>preg</i> +against a given <i>string</i>, which is by default terminated by a zero byte +(but see REG_STARTEND below), subject to the options in <i>eflags</i>. These can +be: <pre> REG_NOTBOL </pre> @@ -293,7 +272,7 @@ are mutually exclusive; the error REG_INVARG is returned. <P> If the pattern was compiled with the REG_NOSUB flag, no data about any matched strings is returned. The <i>nmatch</i> and <i>pmatch</i> arguments of -<b>pcre2_regexec()</b> are ignored (except possibly as input for REG_STARTEND). +<b>regexec()</b> are ignored (except possibly as input for REG_STARTEND). </P> <P> The value of <i>nmatch</i> may be zero, and the value <i>pmatch</i> may be NULL @@ -315,25 +294,24 @@ array have both structure members set to -1. A successful match yields a zero return; various error codes are defined in the header file, of which REG_NOMATCH is the "expected" failure code. </P> -<br><a name="SEC7" href="#TOC1">ERROR MESSAGES</a><br> +<br><a name="SEC6" href="#TOC1">ERROR MESSAGES</a><br> <P> -The <b>pcre2_regerror()</b> function maps a non-zero errorcode from either -<b>pcre2_regcomp()</b> or <b>pcre2_regexec()</b> to a printable message. If -<i>preg</i> is not NULL, the error should have arisen from the use of that -structure. A message terminated by a binary zero is placed in <i>errbuf</i>. If -the buffer is too short, only the first <i>errbuf_size</i> - 1 characters of the -error message are used. The yield of the function is the size of buffer needed -to hold the whole message, including the terminating zero. This value is -greater than <i>errbuf_size</i> if the message was truncated. +The <b>regerror()</b> function maps a non-zero errorcode from either +<b>regcomp()</b> or <b>regexec()</b> to a printable message. If <i>preg</i> is not +NULL, the error should have arisen from the use of that structure. A message +terminated by a binary zero is placed in <i>errbuf</i>. If the buffer is too +short, only the first <i>errbuf_size</i> - 1 characters of the error message are +used. The yield of the function is the size of buffer needed to hold the whole +message, including the terminating zero. This value is greater than +<i>errbuf_size</i> if the message was truncated. </P> -<br><a name="SEC8" href="#TOC1">MEMORY USAGE</a><br> +<br><a name="SEC7" href="#TOC1">MEMORY USAGE</a><br> <P> Compiling a regular expression causes memory to be allocated and associated -with the <i>preg</i> structure. The function <b>pcre2_regfree()</b> frees all -such memory, after which <i>preg</i> may no longer be used as a compiled -expression. +with the <i>preg</i> structure. The function <b>regfree()</b> frees all such +memory, after which <i>preg</i> may no longer be used as a compiled expression. </P> -<br><a name="SEC9" href="#TOC1">AUTHOR</a><br> +<br><a name="SEC8" href="#TOC1">AUTHOR</a><br> <P> Philip Hazel <br> @@ -342,11 +320,11 @@ University Computing Service Cambridge, England. <br> </P> -<br><a name="SEC10" href="#TOC1">REVISION</a><br> +<br><a name="SEC9" href="#TOC1">REVISION</a><br> <P> -Last updated: 30 January 2019 +Last updated: 15 June 2017 <br> -Copyright © 1997-2019 University of Cambridge. +Copyright © 1997-2017 University of Cambridge. <br> <p> Return to the <a href="index.html">PCRE2 index page</a>. |