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diff --git a/srclib/pcre/doc/html/pcreposix.html b/srclib/pcre/doc/html/pcreposix.html deleted file mode 100644 index 2f7aaa9d9c..0000000000 --- a/srclib/pcre/doc/html/pcreposix.html +++ /dev/null @@ -1,218 +0,0 @@ -<html> -<head> -<title>pcreposix specification</title> -</head> -<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> -<h1>pcreposix man page</h1> -<p> -Return to the <a href="index.html">PCRE index page</a>. -</p> -<p> -This page is part of the PCRE HTML documentation. It was 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">MEMORY USAGE</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 PCRE's 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 that uses them. Because the POSIX functions -call the native ones, it is also necessary to add <b>-lpcre</b>. -</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> -<P> -</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 <b>regex_t</b> structure that 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: -<pre> - REG_ICASE -</pre> -The PCRE_CASELESS option is set when the expression is passed for compilation -to the native function. -<pre> - REG_NEWLINE -</pre> -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: -<pre> - Default Change with - - . 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> -This is the equivalent table for POSIX: -<pre> - Default Change with - - . 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> -PCRE's behaviour is the same as Perl's, except that there is no equivalent for -PCRE_DOLLAR_ENDONLY 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_DOLLAR_ENDONLY, 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 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: -<pre> - REG_NOTBOL -</pre> -The PCRE_NOTBOL option is set when calling the underlying PCRE matching -function. -<pre> - REG_NOTEOL -</pre> -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">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>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: 07 September 2004 -<br> -Copyright © 1997-2004 University of Cambridge. -<p> -Return to the <a href="index.html">PCRE index page</a>. -</p> |