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diff --git a/srclib/pcre/doc/html/pcreprecompile.html b/srclib/pcre/doc/html/pcreprecompile.html deleted file mode 100644 index f1c109e7c3..0000000000 --- a/srclib/pcre/doc/html/pcreprecompile.html +++ /dev/null @@ -1,133 +0,0 @@ -<html> -<head> -<title>pcreprecompile specification</title> -</head> -<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> -<h1>pcreprecompile 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">SAVING AND RE-USING PRECOMPILED PCRE PATTERNS</a> -<li><a name="TOC2" href="#SEC2">SAVING A COMPILED PATTERN</a> -<li><a name="TOC3" href="#SEC3">RE-USING A PRECOMPILED PATTERN</a> -<li><a name="TOC4" href="#SEC4">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a> -</ul> -<br><a name="SEC1" href="#TOC1">SAVING AND RE-USING PRECOMPILED PCRE PATTERNS</a><br> -<P> -If you are running an application that uses a large number of regular -expression patterns, it may be useful to store them in a precompiled form -instead of having to compile them every time the application is run. -If you are not using any private character tables (see the -<a href="pcre_maketables.html"><b>pcre_maketables()</b></a> -documentation), this is relatively straightforward. If you are using private -tables, it is a little bit more complicated. -</P> -<P> -If you save compiled patterns to a file, you can copy them to a different host -and run them there. This works even if the new host has the opposite endianness -to the one on which the patterns were compiled. There may be a small -performance penalty, but it should be insignificant. -</P> -<br><a name="SEC2" href="#TOC1">SAVING A COMPILED PATTERN</a><br> -<P> -The value returned by <b>pcre_compile()</b> points to a single block of memory -that holds the compiled pattern and associated data. You can find the length of -this block in bytes by calling <b>pcre_fullinfo()</b> with an argument of -PCRE_INFO_SIZE. You can then save the data in any appropriate manner. Here is -sample code that compiles a pattern and writes it to a file. It assumes that -the variable <i>fd</i> refers to a file that is open for output: -<pre> - int erroroffset, rc, size; - char *error; - pcre *re; - - re = pcre_compile("my pattern", 0, &error, &erroroffset, NULL); - if (re == NULL) { ... handle errors ... } - rc = pcre_fullinfo(re, NULL, PCRE_INFO_SIZE, &size); - if (rc < 0) { ... handle errors ... } - rc = fwrite(re, 1, size, fd); - if (rc != size) { ... handle errors ... } -</pre> -In this example, the bytes that comprise the compiled pattern are copied -exactly. Note that this is binary data that may contain any of the 256 possible -byte values. On systems that make a distinction between binary and non-binary -data, be sure that the file is opened for binary output. -</P> -<P> -If you want to write more than one pattern to a file, you will have to devise a -way of separating them. For binary data, preceding each pattern with its length -is probably the most straightforward approach. Another possibility is to write -out the data in hexadecimal instead of binary, one pattern to a line. -</P> -<P> -Saving compiled patterns in a file is only one possible way of storing them for -later use. They could equally well be saved in a database, or in the memory of -some daemon process that passes them via sockets to the processes that want -them. -</P> -<P> -If the pattern has been studied, it is also possible to save the study data in -a similar way to the compiled pattern itself. When studying generates -additional information, <b>pcre_study()</b> returns a pointer to a -<b>pcre_extra</b> data block. Its format is defined in the -<a href="pcreapi.html#extradata">section on matching a pattern</a> -in the -<a href="pcreapi.html"><b>pcreapi</b></a> -documentation. The <i>study_data</i> field points to the binary study data, and -this is what you must save (not the <b>pcre_extra</b> block itself). The length -of the study data can be obtained by calling <b>pcre_fullinfo()</b> with an -argument of PCRE_INFO_STUDYSIZE. Remember to check that <b>pcre_study()</b> did -return a non-NULL value before trying to save the study data. -</P> -<br><a name="SEC3" href="#TOC1">RE-USING A PRECOMPILED PATTERN</a><br> -<P> -Re-using a precompiled pattern is straightforward. Having reloaded it into main -memory, you pass its pointer to <b>pcre_exec()</b> in the usual way. This should -work even on another host, and even if that host has the opposite endianness to -the one where the pattern was compiled. -</P> -<P> -However, if you passed a pointer to custom character tables when the pattern -was compiled (the <i>tableptr</i> argument of <b>pcre_compile()</b>), you must -now pass a similar pointer to <b>pcre_exec()</b>, because the value saved with -the compiled pattern will obviously be nonsense. A field in a -<b>pcre_extra()</b> block is used to pass this data, as described in the -<a href="pcreapi.html#extradata">section on matching a pattern</a> -in the -<a href="pcreapi.html"><b>pcreapi</b></a> -documentation. -</P> -<P> -If you did not provide custom character tables when the pattern was compiled, -the pointer in the compiled pattern is NULL, which causes <b>pcre_exec()</b> to -use PCRE's internal tables. Thus, you do not need to take any special action at -run time in this case. -</P> -<P> -If you saved study data with the compiled pattern, you need to create your own -<b>pcre_extra</b> data block and set the <i>study_data</i> field to point to the -reloaded study data. You must also set the PCRE_EXTRA_STUDY_DATA bit in the -<i>flags</i> field to indicate that study data is present. Then pass the -<b>pcre_extra</b> block to <b>pcre_exec()</b> in the usual way. -</P> -<br><a name="SEC4" href="#TOC1">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a><br> -<P> -The layout of the control block that is at the start of the data that makes up -a compiled pattern was changed for release 5.0. If you have any saved patterns -that were compiled with previous releases (not a facility that was previously -advertised), you will have to recompile them for release 5.0. However, from now -on, it should be possible to make changes in a compabible manner. -</P> -<P> -Last updated: 10 September 2004 -<br> -Copyright © 1997-2004 University of Cambridge. -<p> -Return to the <a href="index.html">PCRE index page</a>. -</p> |