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revision 683 by ph10, Tue Sep 6 10:37:15 2011 UTC revision 686 by ph10, Tue Sep 6 16:06:36 2011 UTC
# Line 111  PCRE - Perl-compatible regular expressio Line 111  PCRE - Perl-compatible regular expressio
111  .B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);  .B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);
112  .PP  .PP
113  .B char *pcre_version(void);  .B char *pcre_version(void);
114  .PP  .
115    .
116    .SH "PCRE NATIVE API INDIRECTED FUNCTIONS"
117    .rs
118    .sp
119  .B void *(*pcre_malloc)(size_t);  .B void *(*pcre_malloc)(size_t);
120  .PP  .PP
121  .B void (*pcre_free)(void *);  .B void (*pcre_free)(void *);
# Line 168  documentation, and the Line 172  documentation, and the
172  documentation describes how to compile and run it.  documentation describes how to compile and run it.
173  .P  .P
174  Just-in-time compiler support is an optional feature of PCRE that can be built  Just-in-time compiler support is an optional feature of PCRE that can be built
175  in appropriate hardware environments. It greatly speeds up the matching  in appropriate hardware environments. It greatly speeds up the matching
176  performance of many patterns. Simple programs can request its use if available.  performance of many patterns. Simple programs can easily request that it be
177  More complicated programs might need to make use of the  used if available, by setting an option that is ignored when it is not
178  \fBpcre_jit_stack_alloc()\fP, \fBpcre_jit_stack_free()\fP, and  relevant. More complicated programs might need to make use of the functions
179  \fBpcre_assign_jit_stack()\fP functions in order to control its memory usage.  \fBpcre_jit_stack_alloc()\fP, \fBpcre_jit_stack_free()\fP, and
180    \fBpcre_assign_jit_stack()\fP in order to control the JIT code's memory usage.
181  These functions are discussed in the  These functions are discussed in the
182  .\" HREF  .\" HREF
183  \fBpcrejit\fP  \fBpcrejit\fP
# Line 1430  This limit is of use only if it is set s Line 1435  This limit is of use only if it is set s
1435  .P  .P
1436  Limiting the recursion depth limits the amount of machine stack that can be  Limiting the recursion depth limits the amount of machine stack that can be
1437  used, or, when PCRE has been compiled to use memory on the heap instead of the  used, or, when PCRE has been compiled to use memory on the heap instead of the
1438  stack, the amount of heap memory that can be used. This limit is relevant, and  stack, the amount of heap memory that can be used. This limit is not relevant,
1439  is ignored, when the pattern was successfully studied with  and is ignored, if the pattern was successfully studied with
1440  PCRE_STUDY_JIT_COMPILE.  PCRE_STUDY_JIT_COMPILE.
1441  .P  .P
1442  The default value for \fImatch_limit_recursion\fP can be set when PCRE is  The default value for \fImatch_limit_recursion\fP can be set when PCRE is
# Line 1491  zero. The only bits that may be set are Line 1496  zero. The only bits that may be set are
1496  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
1497  PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and  PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and
1498  PCRE_PARTIAL_HARD.  PCRE_PARTIAL_HARD.
1499    .P
1500    If the pattern was successfully studied with the PCRE_STUDY_JIT_COMPILE option,
1501    the only supported options for JIT execution are PCRE_NO_UTF8_CHECK,
1502    PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, and PCRE_NOTEMPTY_ATSTART. Note in
1503    particular that partial matching is not supported. If an unsupported option is
1504    used, JIT execution is disabled and the normal interpretive code in
1505    \fBpcre_exec()\fP is run.
1506  .sp  .sp
1507    PCRE_ANCHORED    PCRE_ANCHORED
1508  .sp  .sp
# Line 1797  string that it matched that is returned. Line 1809  string that it matched that is returned.
1809  .P  .P
1810  If the vector is too small to hold all the captured substring offsets, it is  If the vector is too small to hold all the captured substring offsets, it is
1811  used as far as possible (up to two-thirds of its length), and the function  used as far as possible (up to two-thirds of its length), and the function
1812  returns a value of zero. If the substring offsets are not of interest,  returns a value of zero. If neither the actual string matched not any captured
1813  \fBpcre_exec()\fP may be called with \fIovector\fP passed as NULL and  substrings are of interest, \fBpcre_exec()\fP may be called with \fIovector\fP
1814  \fIovecsize\fP as zero. However, if the pattern contains back references and  passed as NULL and \fIovecsize\fP as zero. However, if the pattern contains
1815  the \fIovector\fP is not big enough to remember the related substrings, PCRE  back references and the \fIovector\fP is not big enough to remember the related
1816  has to get additional memory for use during matching. Thus it is usually  substrings, PCRE has to get additional memory for use during matching. Thus it
1817  advisable to supply an \fIovector\fP.  is usually advisable to supply an \fIovector\fP of reasonable size.
1818    .P
1819    There are some cases where zero is returned (indicating vector overflow) when
1820    in fact the vector is exactly the right size for the final match. For example,
1821    consider the pattern
1822    .sp
1823      (a)(?:(b)c|bd)
1824    .sp
1825    If a vector of 6 elements (allowing for only 1 captured substring) is given
1826    with subject string "abd", \fBpcre_exec()\fP will try to set the second
1827    captured string, thereby recording a vector overflow, before failing to match
1828    "c" and backing up to try the second alternative. The zero return, however,
1829    does correctly indicate that the maximum number of slots (namely 2) have been
1830    filled. In similar cases where there is temporary overflow, but the final
1831    number of used slots is actually less than the maximum, a non-zero value is
1832    returned.
1833  .P  .P
1834  The \fBpcre_fullinfo()\fP function can be used to find out how many capturing  The \fBpcre_fullinfo()\fP function can be used to find out how many capturing
1835  subpatterns there are in a compiled pattern. The smallest size for  subpatterns there are in a compiled pattern. The smallest size for
# Line 1823  return from the function is 2, because t Line 1850  return from the function is 2, because t
1850  number is 1, and the offsets for for the second and third capturing subpatterns  number is 1, and the offsets for for the second and third capturing subpatterns
1851  (assuming the vector is large enough, of course) are set to -1.  (assuming the vector is large enough, of course) are set to -1.
1852  .P  .P
1853  \fBNote\fP: Elements in the first two-thids of \fIovector\fP that do not  \fBNote\fP: Elements in the first two-thirds of \fIovector\fP that do not
1854  correspond to capturing parentheses in the pattern are never changed. That is,  correspond to capturing parentheses in the pattern are never changed. That is,
1855  if a pattern contains \fIn\fP capturing parentheses, no more than  if a pattern contains \fIn\fP capturing parentheses, no more than
1856  \fIovector[0]\fP to \fIovector[2n+1]\fP are set by \fBpcre_exec()\fP. The other  \fIovector[0]\fP to \fIovector[2n+1]\fP are set by \fBpcre_exec()\fP. The other
# Line 1983  time. Line 2010  time.
2010    PCRE_ERROR_JIT_STACKLIMIT (-27)    PCRE_ERROR_JIT_STACKLIMIT (-27)
2011  .sp  .sp
2012  This error is returned when a pattern that was successfully studied using the  This error is returned when a pattern that was successfully studied using the
2013  PCRE_STUDY_JIT_COMPILE option is matched, but the memory available for the  PCRE_STUDY_JIT_COMPILE option is being matched, but the memory available for
2014  just-in-time processing stack is not large enough. See the  the just-in-time processing stack is not large enough. See the
2015  .\" HREF  .\" HREF
2016  \fBpcrejit\fP  \fBpcrejit\fP
2017  .\"  .\"
# Line 2229  names are not included in the compiled c Line 2256  names are not included in the compiled c
2256  numbers. For this reason, the use of different names for subpatterns of the  numbers. For this reason, the use of different names for subpatterns of the
2257  same number causes an error at compile time.  same number causes an error at compile time.
2258  .  .
2259    .
2260  .SH "DUPLICATE SUBPATTERN NAMES"  .SH "DUPLICATE SUBPATTERN NAMES"
2261  .rs  .rs
2262  .sp  .sp
# Line 2498  Cambridge CB2 3QH, England. Line 2526  Cambridge CB2 3QH, England.
2526  .rs  .rs
2527  .sp  .sp
2528  .nf  .nf
2529  Last updated: 29 August 2011  Last updated: 06 September 2011
2530  Copyright (c) 1997-2011 University of Cambridge.  Copyright (c) 1997-2011 University of Cambridge.
2531  .fi  .fi

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