Update bundled PCRE2-library to version 10.23
Some manual changes done to the library were lost with this update. They will be added in the next commit.
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@ -12,17 +12,21 @@ This page is part of the PCRE2 HTML documentation. It was generated
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automatically from the original man page. If there is any nonsense in it,
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please consult the man page, in case the conversion went wrong.
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<br>
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<br><b>
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PCRE2 PERFORMANCE
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</b><br>
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<ul>
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<li><a name="TOC1" href="#SEC1">PCRE2 PERFORMANCE</a>
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<li><a name="TOC2" href="#SEC2">COMPILED PATTERN MEMORY USAGE</a>
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<li><a name="TOC3" href="#SEC3">STACK USAGE AT RUN TIME</a>
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<li><a name="TOC4" href="#SEC4">PROCESSING TIME</a>
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<li><a name="TOC5" href="#SEC5">AUTHOR</a>
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<li><a name="TOC6" href="#SEC6">REVISION</a>
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</ul>
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<br><a name="SEC1" href="#TOC1">PCRE2 PERFORMANCE</a><br>
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<P>
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Two aspects of performance are discussed below: memory usage and processing
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time. The way you express your pattern as a regular expression can affect both
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of them.
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</P>
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<br><b>
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COMPILED PATTERN MEMORY USAGE
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</b><br>
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<br><a name="SEC2" href="#TOC1">COMPILED PATTERN MEMORY USAGE</a><br>
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<P>
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Patterns are compiled by PCRE2 into a reasonably efficient interpretive code,
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so that most simple patterns do not use much memory. However, there is one case
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@ -75,9 +79,7 @@ pattern. Nevertheless, if the atomic grouping is not a problem and the loss of
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speed is acceptable, this kind of rewriting will allow you to process patterns
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that PCRE2 cannot otherwise handle.
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</P>
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<br><b>
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STACK USAGE AT RUN TIME
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</b><br>
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<br><a name="SEC3" href="#TOC1">STACK USAGE AT RUN TIME</a><br>
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<P>
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When <b>pcre2_match()</b> is used for matching, certain kinds of pattern can
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cause it to use large amounts of the process stack. In some environments the
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@ -86,9 +88,7 @@ SIGSEGV. Rewriting your pattern can often help. The
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<a href="pcre2stack.html"><b>pcre2stack</b></a>
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documentation discusses this issue in detail.
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</P>
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<br><b>
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PROCESSING TIME
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</b><br>
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<br><a name="SEC4" href="#TOC1">PROCESSING TIME</a><br>
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<P>
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Certain items in regular expression patterns are processed more efficiently
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than others. It is more efficient to use a character class like [aeiou] than a
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@ -177,9 +177,7 @@ appreciable time with strings longer than about 20 characters.
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In many cases, the solution to this kind of performance issue is to use an
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atomic group or a possessive quantifier.
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</P>
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<br><b>
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AUTHOR
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</b><br>
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<br><a name="SEC5" href="#TOC1">AUTHOR</a><br>
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<P>
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Philip Hazel
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<br>
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@ -188,9 +186,7 @@ University Computing Service
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Cambridge, England.
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<br>
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</P>
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<br><b>
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REVISION
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</b><br>
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<br><a name="SEC6" href="#TOC1">REVISION</a><br>
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<P>
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Last updated: 02 January 2015
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<br>
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