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Diff for /embedaddon/pcre/doc/pcreperform.3 between versions 1.1.1.3 and 1.1.1.4

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version 1.1.1.3, 2012/10/09 09:19:17	version 1.1.1.4, 2013/07/22 08:25:56
Line 68 that PCRE cannot otherwise handle.	Line 68 that PCRE cannot otherwise handle.
.SH "STACK USAGE AT RUN TIME"	.SH "STACK USAGE AT RUN TIME"
.rs	.rs
.sp	.sp
When \fBpcre_exec()\fP or \fBpcre16_exec()\fP is used for matching, certain	When \fBpcre_exec()\fP or \fBpcre[16\|32]_exec()\fP is used for matching, certain
kinds of pattern can cause it to use large amounts of the process stack. In	kinds of pattern can cause it to use large amounts of the process stack. In
some environments the default process stack is quite small, and if it runs out	some environments the default process stack is quite small, and if it runs out
the result is often SIGSEGV. This issue is probably the most frequently raised	the result is often SIGSEGV. This issue is probably the most frequently raised
Line 91 about optimizing regular expressions for efficient per	Line 91 about optimizing regular expressions for efficient per
contains a few observations about PCRE.	contains a few observations about PCRE.
.P	.P
Using Unicode character properties (the \ep, \eP, and \eX escapes) is slow,	Using Unicode character properties (the \ep, \eP, and \eX escapes) is slow,
because PCRE has to scan a structure that contains data for over fifteen	because PCRE has to use a multi-stage table lookup whenever it needs a
thousand characters whenever it needs a character's property. If you can find	character's property. If you can find an alternative pattern that does not use
an alternative pattern that does not use character properties, it will probably	character properties, it will probably be faster.
be faster.
.P	.P
By default, the escape sequences \eb, \ed, \es, and \ew, and the POSIX	By default, the escape sequences \eb, \ed, \es, and \ew, and the POSIX
character classes such as [:alpha:] do not use Unicode properties, partly for	character classes such as [:alpha:] do not use Unicode properties, partly for
Line 173 Cambridge CB2 3QH, England.	Line 172 Cambridge CB2 3QH, England.
.rs	.rs
.sp	.sp
.nf	.nf
Last updated: 09 January 2012	Last updated: 25 August 2012
Copyright (c) 1997-2012 University of Cambridge.	Copyright (c) 1997-2012 University of Cambridge.
.fi	.fi

Removed from v.1.1.1.3
changed lines
	Added in v.1.1.1.4