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diff --git a/external-libs/pcre/doc/html/pcreposix.html b/external-libs/pcre/doc/html/pcreposix.html new file mode 100644 index 00000000..d0a5e127 --- /dev/null +++ b/external-libs/pcre/doc/html/pcreposix.html @@ -0,0 +1,237 @@ +<html> +<head> +<title>pcreposix specification</title> +</head> +<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> +This HTML document has been generated automatically from the original man page. +If there is any nonsense in it, please consult the man page, in case the +conversion went wrong.<br> +<ul> +<li><a name="TOC1" href="#SEC1">SYNOPSIS OF POSIX API</a> +<li><a name="TOC2" href="#SEC2">DESCRIPTION</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">STORAGE</a> +<li><a name="TOC8" href="#SEC8">AUTHOR</a> +</ul> +<br><a name="SEC1" href="#TOC1">SYNOPSIS OF POSIX API</a><br> +<P> +<b>#include <pcreposix.h></b> +</P> +<P> +<b>int regcomp(regex_t *<i>preg</i>, const char *<i>pattern</i>,</b> +<b>int <i>cflags</i>);</b> +</P> +<P> +<b>int regexec(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> +</P> +<P> +<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> +</P> +<P> +<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 to the PCRE regular expression +package. See the +<a href="pcreapi.html"><b>pcreapi</b></a> +documentation for a description of the native API, which contains additional +functionality. +</P> +<P> +The functions described here are just wrapper functions that ultimately call +the PCRE native API. Their prototypes are defined in the <b>pcreposix.h</b> +header file, and on Unix systems the library itself is called +<b>pcreposix.a</b>, so can be accessed by adding <b>-lpcreposix</b> to the +command for linking an application which uses them. Because the POSIX functions +call the native ones, it is also necessary to add \fR-lpcre\fR. +</P> +<P> +I have implemented only those option bits that can be reasonably mapped to PCRE +native options. In addition, the options REG_EXTENDED and REG_NOSUB are defined +with the value zero. They have no effect, but since programs that are written +to the POSIX interface often use them, this makes it easier to slot in PCRE as +a replacement library. Other POSIX options are not even defined. +</P> +<P> +When PCRE is called via these functions, it is only the API that is POSIX-like +in style. The syntax and semantics of the regular expressions themselves are +still those of Perl, subject to the setting of various PCRE options, as +described below. "POSIX-like in style" means that the API approximates to the +POSIX definition; it is not fully POSIX-compatible, and in multi-byte encoding +domains it is probably even less compatible. +</P> +<P> +The header for these functions is supplied as <b>pcreposix.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="SEC3" href="#TOC1">COMPILING A PATTERN</a><br> +<P> +The function <b>regcomp()</b> is called to compile a pattern into an +internal form. The pattern is a C string terminated by a binary zero, and +is passed in the argument <i>pattern</i>. The <i>preg</i> argument is a pointer +to a regex_t structure which is used as a base for storing information about +the compiled expression. +</P> +<P> +The argument <i>cflags</i> is either zero, or contains one or more of the bits +defined by the following macros: +</P> +<P> +<pre> + REG_ICASE +</PRE> +</P> +<P> +The PCRE_CASELESS option is set when the expression is passed for compilation +to the native function. +</P> +<P> +<pre> + REG_NEWLINE +</PRE> +</P> +<P> +The PCRE_MULTILINE option is set when the expression is passed for compilation +to the native function. Note that this does <i>not</i> mimic the defined POSIX +behaviour for REG_NEWLINE (see the following section). +</P> +<P> +In the absence of these flags, no options are passed to the native function. +This means the the regex is compiled with PCRE default semantics. In +particular, the way it handles newline characters in the subject string is the +Perl way, not the POSIX way. Note that setting PCRE_MULTILINE has only +<i>some</i> of the effects specified for REG_NEWLINE. It does not affect the way +newlines are matched by . (they aren't) or by a negative class such as [^a] +(they are). +</P> +<P> +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 member of the structure +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> +<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 PCRE to obey POSIX semantics, but then PCRE was never +intended to be a POSIX engine. The following table lists the different +possibilities for matching newline characters in PCRE: +</P> +<P> +<pre> + Default Change with +</PRE> +</P> +<P> +<pre> + . matches newline no PCRE_DOTALL + newline matches [^a] yes not changeable + $ matches \n at end yes PCRE_DOLLARENDONLY + $ matches \n in middle no PCRE_MULTILINE + ^ matches \n in middle no PCRE_MULTILINE +</PRE> +</P> +<P> +This is the equivalent table for POSIX: +</P> +<P> +<pre> + Default Change with +</PRE> +</P> +<P> +<pre> + . matches newline yes REG_NEWLINE + newline matches [^a] yes REG_NEWLINE + $ matches \n at end no REG_NEWLINE + $ matches \n in middle no REG_NEWLINE + ^ matches \n in middle no REG_NEWLINE +</PRE> +</P> +<P> +PCRE's behaviour is the same as Perl's, except that there is no equivalent for +PCRE_DOLLARENDONLY in Perl. In both PCRE and Perl, there is no way to stop +newline from matching [^a]. +</P> +<P> +The default POSIX newline handling can be obtained by setting PCRE_DOTALL and +PCRE_DOLLARENDONLY, but there is no way to make PCRE behave exactly as for the +REG_NEWLINE action. +</P> +<br><a name="SEC5" href="#TOC1">MATCHING A PATTERN</a><br> +<P> +The function <b>regexec()</b> is called to match a pre-compiled pattern +<i>preg</i> against a given <i>string</i>, which is terminated by a zero byte, +subject to the options in <i>eflags</i>. These can be: +</P> +<P> +<pre> + REG_NOTBOL +</PRE> +</P> +<P> +The PCRE_NOTBOL option is set when calling the underlying PCRE matching +function. +</P> +<P> +<pre> + REG_NOTEOL +</PRE> +</P> +<P> +The PCRE_NOTEOL option is set when calling the underlying PCRE matching +function. +</P> +<P> +The portion of the string that was matched, and also any captured substrings, +are returned via the <i>pmatch</i> argument, which points to an array of +<i>nmatch</i> structures of type <i>regmatch_t</i>, containing the members +<i>rm_so</i> and <i>rm_eo</i>. These contain the offset to the first character of +each substring and the offset to the first character after the end of each +substring, respectively. The 0th element of the vector relates to the entire +portion of <i>string</i> that was matched; subsequent elements relate to the +capturing subpatterns of the regular expression. Unused entries in the array +have both structure members set to -1. +</P> +<P> +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="SEC6" href="#TOC1">ERROR MESSAGES</a><br> +<P> +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>. The length of the +message, including the zero, is limited to <i>errbuf_size</i>. The yield of the +function is the size of buffer needed to hold the whole message. +</P> +<br><a name="SEC7" href="#TOC1">STORAGE</a><br> +<P> +Compiling a regular expression causes memory to be allocated and associated +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="SEC8" href="#TOC1">AUTHOR</a><br> +<P> +Philip Hazel <ph10@cam.ac.uk> +<br> +University Computing Service, +<br> +Cambridge CB2 3QG, England. +</P> +<P> +Last updated: 03 February 2003 +<br> +Copyright © 1997-2003 University of Cambridge. |