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diff --git a/external-libs/pcre/doc/html/pcrecallout.html b/external-libs/pcre/doc/html/pcrecallout.html deleted file mode 100644 index f4b7104e..00000000 --- a/external-libs/pcre/doc/html/pcrecallout.html +++ /dev/null @@ -1,117 +0,0 @@ -<html> -<head> -<title>pcrecallout 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">PCRE CALLOUTS</a> -<li><a name="TOC2" href="#SEC2">RETURN VALUES</a> -</ul> -<br><a name="SEC1" href="#TOC1">PCRE CALLOUTS</a><br> -<P> -<b>int (*pcre_callout)(pcre_callout_block *);</b> -</P> -<P> -PCRE provides a feature called "callout", which is a means of temporarily -passing control to the caller of PCRE in the middle of pattern matching. The -caller of PCRE provides an external function by putting its entry point in the -global variable <i>pcre_callout</i>. By default, this variable contains NULL, -which disables all calling out. -</P> -<P> -Within a regular expression, (?C) indicates the points at which the external -function is to be called. Different callout points can be identified by putting -a number less than 256 after the letter C. The default value is zero. -For example, this pattern has two callout points: -</P> -<P> -<pre> - (?C1)\dabc(?C2)def -</PRE> -</P> -<P> -During matching, when PCRE reaches a callout point (and <i>pcre_callout</i> is -set), the external function is called. Its only argument is a pointer to a -<b>pcre_callout</b> block. This contains the following variables: -</P> -<P> -<pre> - int <i>version</i>; - int <i>callout_number</i>; - int *<i>offset_vector</i>; - const char *<i>subject</i>; - int <i>subject_length</i>; - int <i>start_match</i>; - int <i>current_position</i>; - int <i>capture_top</i>; - int <i>capture_last</i>; - void *<i>callout_data</i>; -</PRE> -</P> -<P> -The <i>version</i> field is an integer containing the version number of the -block format. The current version is zero. The version number may change in -future if additional fields are added, but the intention is never to remove any -of the existing fields. -</P> -<P> -The <i>callout_number</i> field contains the number of the callout, as compiled -into the pattern (that is, the number after ?C). -</P> -<P> -The <i>offset_vector</i> field is a pointer to the vector of offsets that was -passed by the caller to <b>pcre_exec()</b>. The contents can be inspected in -order to extract substrings that have been matched so far, in the same way as -for extracting substrings after a match has completed. -</P> -<P> -The <i>subject</i> and <i>subject_length</i> fields contain copies the values -that were passed to <b>pcre_exec()</b>. -</P> -<P> -The <i>start_match</i> field contains the offset within the subject at which the -current match attempt started. If the pattern is not anchored, the callout -function may be called several times for different starting points. -</P> -<P> -The <i>current_position</i> field contains the offset within the subject of the -current match pointer. -</P> -<P> -The <i>capture_top</i> field contains one more than the number of the highest -numbered captured substring so far. If no substrings have been captured, -the value of <i>capture_top</i> is one. -</P> -<P> -The <i>capture_last</i> field contains the number of the most recently captured -substring. -</P> -<P> -The <i>callout_data</i> field contains a value that is passed to -<b>pcre_exec()</b> by the caller specifically so that it can be passed back in -callouts. It is passed in the <i>pcre_callout</i> field of the <b>pcre_extra</b> -data structure. If no such data was passed, the value of <i>callout_data</i> in -a <b>pcre_callout</b> block is NULL. There is a description of the -<b>pcre_extra</b> structure in the <b>pcreapi</b> documentation. -</P> -<br><a name="SEC2" href="#TOC1">RETURN VALUES</a><br> -<P> -The callout function returns an integer. If the value is zero, matching -proceeds as normal. If the value is greater than zero, matching fails at the -current point, but backtracking to test other possibilities goes ahead, just as -if a lookahead assertion had failed. If the value is less than zero, the match -is abandoned, and <b>pcre_exec()</b> returns the value. -</P> -<P> -Negative values should normally be chosen from the set of PCRE_ERROR_xxx -values. In particular, PCRE_ERROR_NOMATCH forces a standard "no match" failure. -The error number PCRE_ERROR_CALLOUT is reserved for use by callout functions; -it will never be used by PCRE itself. -</P> -<P> -Last updated: 21 January 2003 -<br> -Copyright © 1997-2003 University of Cambridge. |