Revision: 416
http://vcs.pcre.org/viewvc?view=rev&revision=416
Author: ph10
Date: 2009-04-11 15:34:02 +0100 (Sat, 11 Apr 2009)
Log Message:
-----------
File tidies for 7.9 release.
Modified Paths:
--------------
code/trunk/AUTHORS
code/trunk/CMakeLists.txt
code/trunk/ChangeLog
code/trunk/LICENCE
code/trunk/doc/html/pcre.html
code/trunk/doc/html/pcreapi.html
code/trunk/doc/html/pcrepattern.html
code/trunk/doc/html/pcresyntax.html
code/trunk/doc/pcre.txt
code/trunk/doc/pcrepattern.3
code/trunk/doc/pcresyntax.3
code/trunk/pcretest.c
Modified: code/trunk/AUTHORS
===================================================================
--- code/trunk/AUTHORS 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/AUTHORS 2009-04-11 14:34:02 UTC (rev 416)
@@ -8,7 +8,7 @@
University of Cambridge Computing Service,
Cambridge, England.
-Copyright (c) 1997-2008 University of Cambridge
+Copyright (c) 1997-2009 University of Cambridge
All rights reserved
Modified: code/trunk/CMakeLists.txt
===================================================================
--- code/trunk/CMakeLists.txt 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/CMakeLists.txt 2009-04-11 14:34:02 UTC (rev 416)
@@ -523,10 +523,10 @@
STRING(TOUPPER "${CMAKE_BUILD_TYPE}" buildtype)
IF (CMAKE_C_FLAGS)
SET(cfsp " ")
- ENDIF(CMAKE_C_FLAGS)
+ ENDIF(CMAKE_C_FLAGS)
IF (CMAKE_CXX_FLAGS)
SET(cxxfsp " ")
- ENDIF(CMAKE_CXX_FLAGS)
+ ENDIF(CMAKE_CXX_FLAGS)
MESSAGE(STATUS "")
MESSAGE(STATUS "")
MESSAGE(STATUS "PCRE configuration summary:")
Modified: code/trunk/ChangeLog
===================================================================
--- code/trunk/ChangeLog 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/ChangeLog 2009-04-11 14:34:02 UTC (rev 416)
@@ -112,13 +112,13 @@
26. Changed a few more instances of "const unsigned char *" to USPTR, making
the feature of a custom pointer more persuasive (as requested by a user).
-
+
27. Wrapped the definitions of fileno and isatty for Windows, which appear in
- pcretest.c, inside #ifndefs, because it seems they are sometimes already
- pre-defined.
-
-28. Added support for (*UTF8) at the start of a pattern.
+ pcretest.c, inside #ifndefs, because it seems they are sometimes already
+ pre-defined.
+28. Added support for (*UTF8) at the start of a pattern.
+
29. Arrange for flags added by the "release type" setting in CMake to be shown
in the configuration summary.
Modified: code/trunk/LICENCE
===================================================================
--- code/trunk/LICENCE 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/LICENCE 2009-04-11 14:34:02 UTC (rev 416)
@@ -22,7 +22,7 @@
University of Cambridge Computing Service,
Cambridge, England.
-Copyright (c) 1997-2008 University of Cambridge
+Copyright (c) 1997-2009 University of Cambridge
All rights reserved.
Modified: code/trunk/doc/html/pcre.html
===================================================================
--- code/trunk/doc/html/pcre.html 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/html/pcre.html 2009-04-11 14:34:02 UTC (rev 416)
@@ -34,7 +34,7 @@
Perl 5.10, including support for UTF-8 encoded strings and Unicode general
category properties. However, UTF-8 and Unicode support has to be explicitly
enabled; it is not the default. The Unicode tables correspond to Unicode
-release 5.0.0.
+release 5.1.
</P>
<P>
In addition to the Perl-compatible matching function, PCRE contains an
@@ -160,9 +160,10 @@
In order process UTF-8 strings, you must build PCRE to include UTF-8 support in
the code, and, in addition, you must call
<a href="pcre_compile.html"><b>pcre_compile()</b></a>
-with the PCRE_UTF8 option flag. When you do this, both the pattern and any
-subject strings that are matched against it are treated as UTF-8 strings
-instead of just strings of bytes.
+with the PCRE_UTF8 option flag, or the pattern must start with the sequence
+(*UTF8). When either of these is the case, both the pattern and any subject
+strings that are matched against it are treated as UTF-8 strings instead of
+just strings of bytes.
</P>
<P>
If you compile PCRE with UTF-8 support, but do not use it at run time, the
@@ -296,7 +297,7 @@
</P>
<br><a name="SEC6" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 18 March 2009
+Last updated: 11 April 2009
<br>
Copyright © 1997-2009 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcreapi.html
===================================================================
--- code/trunk/doc/html/pcreapi.html 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/html/pcreapi.html 2009-04-11 14:34:02 UTC (rev 416)
@@ -416,14 +416,15 @@
<P>
The <i>options</i> argument contains various bit settings that affect the
compilation. It should be zero if no options are required. The available
-options are described below. Some of them, in particular, those that are
-compatible with Perl, can also be set and unset from within the pattern (see
-the detailed description in the
+options are described below. Some of them (in particular, those that are
+compatible with Perl, but also some others) can also be set and unset from
+within the pattern (see the detailed description in the
<a href="pcrepattern.html"><b>pcrepattern</b></a>
-documentation). For these options, the contents of the <i>options</i> argument
-specifies their initial settings at the start of compilation and execution. The
-PCRE_ANCHORED and PCRE_NEWLINE_<i>xxx</i> options can be set at the time of
-matching as well as at compile time.
+documentation). For those options that can be different in different parts of
+the pattern, the contents of the <i>options</i> argument specifies their initial
+settings at the start of compilation and execution. The PCRE_ANCHORED and
+PCRE_NEWLINE_<i>xxx</i> options can be set at the time of matching as well as at
+compile time.
</P>
<P>
If <i>errptr</i> is NULL, <b>pcre_compile()</b> returns NULL immediately.
@@ -1995,7 +1996,7 @@
</P>
<br><a name="SEC22" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 17 March 2009
+Last updated: 11 April 2009
<br>
Copyright © 1997-2009 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcrepattern.html
===================================================================
--- code/trunk/doc/html/pcrepattern.html 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/html/pcrepattern.html 2009-04-11 14:34:02 UTC (rev 416)
@@ -63,8 +63,15 @@
The original operation of PCRE was on strings of one-byte characters. However,
there is now also support for UTF-8 character strings. To use this, you must
build PCRE to include UTF-8 support, and then call <b>pcre_compile()</b> with
-the PCRE_UTF8 option. How this affects pattern matching is mentioned in several
-places below. There is also a summary of UTF-8 features in the
+the PCRE_UTF8 option. There is also a special sequence that can be given at the
+start of a pattern:
+<pre>
+ (*UTF8)
+</pre>
+Starting a pattern with this sequence is equivalent to setting the PCRE_UTF8
+option. This feature is not Perl-compatible. How setting UTF-8 mode affects
+pattern matching is mentioned in several places below. There is also a summary
+of UTF-8 features in the
<a href="pcre.html#utf8support">section on UTF-8 support</a>
in the main
<a href="pcre.html"><b>pcre</b></a>
@@ -1031,11 +1038,11 @@
J, U and X respectively.
</P>
<P>
-When an option change occurs at top level (that is, not inside subpattern
-parentheses), the change applies to the remainder of the pattern that follows.
-If the change is placed right at the start of a pattern, PCRE extracts it into
-the global options (and it will therefore show up in data extracted by the
-<b>pcre_fullinfo()</b> function).
+When one of these option changes occurs at top level (that is, not inside
+subpattern parentheses), the change applies to the remainder of the pattern
+that follows. If the change is placed right at the start of a pattern, PCRE
+extracts it into the global options (and it will therefore show up in data
+extracted by the <b>pcre_fullinfo()</b> function).
</P>
<P>
An option change within a subpattern (see below for a description of
@@ -1058,10 +1065,12 @@
<P>
<b>Note:</b> There are other PCRE-specific options that can be set by the
application when the compile or match functions are called. In some cases the
-pattern can contain special leading sequences to override what the application
-has set or what has been defaulted. Details are given in the section entitled
+pattern can contain special leading sequences such as (*CRLF) to override what
+the application has set or what has been defaulted. Details are given in the
+section entitled
<a href="#newlineseq">"Newline sequences"</a>
-above.
+above. There is also the (*UTF8) leading sequence that can be used to set UTF-8
+mode; this is equivalent to setting the PCRE_UTF8 option.
<a name="subpattern"></a></P>
<br><a name="SEC12" href="#TOC1">SUBPATTERNS</a><br>
<P>
@@ -2244,7 +2253,7 @@
</P>
<br><a name="SEC28" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 18 March 2009
+Last updated: 11 April 2009
<br>
Copyright © 1997-2009 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcresyntax.html
===================================================================
--- code/trunk/doc/html/pcresyntax.html 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/html/pcresyntax.html 2009-04-11 14:34:02 UTC (rev 416)
@@ -153,6 +153,8 @@
Buginese,
Buhid,
Canadian_Aboriginal,
+Carian,
+Cham,
Cherokee,
Common,
Coptic,
@@ -176,12 +178,16 @@
Inherited,
Kannada,
Katakana,
+Kayah_Li,
Kharoshthi,
Khmer,
Lao,
Latin,
+Lepcha,
Limbu,
Linear_B,
+Lycian,
+Lydian,
Malayalam,
Mongolian,
Myanmar,
@@ -190,13 +196,17 @@
Ogham,
Old_Italic,
Old_Persian,
+Ol_Chiki,
Oriya,
Osmanya,
Phags_Pa,
Phoenician,
+Rejang,
Runic,
+Saurashtra,
Shavian,
Sinhala,
+Sudanese,
Syloti_Nagri,
Syriac,
Tagalog,
@@ -209,6 +219,7 @@
Tibetan,
Tifinagh,
Ugaritic,
+Vai,
Yi.
</P>
<br><a name="SEC7" href="#TOC1">CHARACTER CLASSES</a><br>
@@ -262,7 +273,7 @@
<br><a name="SEC9" href="#TOC1">ANCHORS AND SIMPLE ASSERTIONS</a><br>
<P>
<pre>
- \b word boundary
+ \b word boundary (only ASCII letters recognized)
\B not a word boundary
^ start of subject
also after internal newline in multiline mode
@@ -291,80 +302,85 @@
<br><a name="SEC12" href="#TOC1">CAPTURING</a><br>
<P>
<pre>
- (...) capturing group
- (?<name>...) named capturing group (Perl)
- (?'name'...) named capturing group (Perl)
- (?P<name>...) named capturing group (Python)
- (?:...) non-capturing group
- (?|...) non-capturing group; reset group numbers for
- capturing groups in each alternative
+ (...) capturing group
+ (?<name>...) named capturing group (Perl)
+ (?'name'...) named capturing group (Perl)
+ (?P<name>...) named capturing group (Python)
+ (?:...) non-capturing group
+ (?|...) non-capturing group; reset group numbers for
+ capturing groups in each alternative
</PRE>
</P>
<br><a name="SEC13" href="#TOC1">ATOMIC GROUPS</a><br>
<P>
<pre>
- (?>...) atomic, non-capturing group
+ (?>...) atomic, non-capturing group
</PRE>
</P>
<br><a name="SEC14" href="#TOC1">COMMENT</a><br>
<P>
<pre>
- (?#....) comment (not nestable)
+ (?#....) comment (not nestable)
</PRE>
</P>
<br><a name="SEC15" href="#TOC1">OPTION SETTING</a><br>
<P>
<pre>
- (?i) caseless
- (?J) allow duplicate names
- (?m) multiline
- (?s) single line (dotall)
- (?U) default ungreedy (lazy)
- (?x) extended (ignore white space)
- (?-...) unset option(s)
+ (?i) caseless
+ (?J) allow duplicate names
+ (?m) multiline
+ (?s) single line (dotall)
+ (?U) default ungreedy (lazy)
+ (?x) extended (ignore white space)
+ (?-...) unset option(s)
+</pre>
+The following is recognized only at the start of a pattern or after one of the
+newline-setting options with similar syntax:
+<pre>
+ (*UTF8) set UTF-8 mode
</PRE>
</P>
<br><a name="SEC16" href="#TOC1">LOOKAHEAD AND LOOKBEHIND ASSERTIONS</a><br>
<P>
<pre>
- (?=...) positive look ahead
- (?!...) negative look ahead
- (?<=...) positive look behind
- (?<!...) negative look behind
+ (?=...) positive look ahead
+ (?!...) negative look ahead
+ (?<=...) positive look behind
+ (?<!...) negative look behind
</pre>
Each top-level branch of a look behind must be of a fixed length.
</P>
<br><a name="SEC17" href="#TOC1">BACKREFERENCES</a><br>
<P>
<pre>
- \n reference by number (can be ambiguous)
- \gn reference by number
- \g{n} reference by number
- \g{-n} relative reference by number
- \k<name> reference by name (Perl)
- \k'name' reference by name (Perl)
- \g{name} reference by name (Perl)
- \k{name} reference by name (.NET)
- (?P=name) reference by name (Python)
+ \n reference by number (can be ambiguous)
+ \gn reference by number
+ \g{n} reference by number
+ \g{-n} relative reference by number
+ \k<name> reference by name (Perl)
+ \k'name' reference by name (Perl)
+ \g{name} reference by name (Perl)
+ \k{name} reference by name (.NET)
+ (?P=name) reference by name (Python)
</PRE>
</P>
<br><a name="SEC18" href="#TOC1">SUBROUTINE REFERENCES (POSSIBLY RECURSIVE)</a><br>
<P>
<pre>
- (?R) recurse whole pattern
- (?n) call subpattern by absolute number
- (?+n) call subpattern by relative number
- (?-n) call subpattern by relative number
- (?&name) call subpattern by name (Perl)
- (?P>name) call subpattern by name (Python)
- \g<name> call subpattern by name (Oniguruma)
- \g'name' call subpattern by name (Oniguruma)
- \g<n> call subpattern by absolute number (Oniguruma)
- \g'n' call subpattern by absolute number (Oniguruma)
- \g<+n> call subpattern by relative number (PCRE extension)
- \g'+n' call subpattern by relative number (PCRE extension)
- \g<-n> call subpattern by relative number (PCRE extension)
- \g'-n' call subpattern by relative number (PCRE extension)
+ (?R) recurse whole pattern
+ (?n) call subpattern by absolute number
+ (?+n) call subpattern by relative number
+ (?-n) call subpattern by relative number
+ (?&name) call subpattern by name (Perl)
+ (?P>name) call subpattern by name (Python)
+ \g<name> call subpattern by name (Oniguruma)
+ \g'name' call subpattern by name (Oniguruma)
+ \g<n> call subpattern by absolute number (Oniguruma)
+ \g'n' call subpattern by absolute number (Oniguruma)
+ \g<+n> call subpattern by relative number (PCRE extension)
+ \g'+n' call subpattern by relative number (PCRE extension)
+ \g<-n> call subpattern by relative number (PCRE extension)
+ \g'-n' call subpattern by relative number (PCRE extension)
</PRE>
</P>
<br><a name="SEC19" href="#TOC1">CONDITIONAL PATTERNS</a><br>
@@ -373,56 +389,56 @@
(?(condition)yes-pattern)
(?(condition)yes-pattern|no-pattern)
- (?(n)... absolute reference condition
- (?(+n)... relative reference condition
- (?(-n)... relative reference condition
- (?(<name>)... named reference condition (Perl)
- (?('name')... named reference condition (Perl)
- (?(name)... named reference condition (PCRE)
- (?(R)... overall recursion condition
- (?(Rn)... specific group recursion condition
- (?(R&name)... specific recursion condition
- (?(DEFINE)... define subpattern for reference
- (?(assert)... assertion condition
+ (?(n)... absolute reference condition
+ (?(+n)... relative reference condition
+ (?(-n)... relative reference condition
+ (?(<name>)... named reference condition (Perl)
+ (?('name')... named reference condition (Perl)
+ (?(name)... named reference condition (PCRE)
+ (?(R)... overall recursion condition
+ (?(Rn)... specific group recursion condition
+ (?(R&name)... specific recursion condition
+ (?(DEFINE)... define subpattern for reference
+ (?(assert)... assertion condition
</PRE>
</P>
<br><a name="SEC20" href="#TOC1">BACKTRACKING CONTROL</a><br>
<P>
The following act immediately they are reached:
<pre>
- (*ACCEPT) force successful match
- (*FAIL) force backtrack; synonym (*F)
+ (*ACCEPT) force successful match
+ (*FAIL) force backtrack; synonym (*F)
</pre>
The following act only when a subsequent match failure causes a backtrack to
reach them. They all force a match failure, but they differ in what happens
afterwards. Those that advance the start-of-match point do so only if the
pattern is not anchored.
<pre>
- (*COMMIT) overall failure, no advance of starting point
- (*PRUNE) advance to next starting character
- (*SKIP) advance start to current matching position
- (*THEN) local failure, backtrack to next alternation
+ (*COMMIT) overall failure, no advance of starting point
+ (*PRUNE) advance to next starting character
+ (*SKIP) advance start to current matching position
+ (*THEN) local failure, backtrack to next alternation
</PRE>
</P>
<br><a name="SEC21" href="#TOC1">NEWLINE CONVENTIONS</a><br>
<P>
These are recognized only at the very start of the pattern or after a
-(*BSR_...) option.
+(*BSR_...) or (*UTF8) option.
<pre>
- (*CR)
- (*LF)
- (*CRLF)
- (*ANYCRLF)
- (*ANY)
+ (*CR) carriage return only
+ (*LF) linefeed only
+ (*CRLF) carriage return followed by linefeed
+ (*ANYCRLF) all three of the above
+ (*ANY) any Unicode newline sequence
</PRE>
</P>
<br><a name="SEC22" href="#TOC1">WHAT \R MATCHES</a><br>
<P>
These are recognized only at the very start of the pattern or after a
-(*...) option that sets the newline convention.
+(*...) option that sets the newline convention or UTF-8 mode.
<pre>
- (*BSR_ANYCRLF)
- (*BSR_UNICODE)
+ (*BSR_ANYCRLF) CR, LF, or CRLF
+ (*BSR_UNICODE) any Unicode newline sequence
</PRE>
</P>
<br><a name="SEC23" href="#TOC1">CALLOUTS</a><br>
@@ -448,9 +464,9 @@
</P>
<br><a name="SEC26" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 09 April 2008
+Last updated: 11 April 2009
<br>
-Copyright © 1997-2008 University of Cambridge.
+Copyright © 1997-2009 University of Cambridge.
<br>
<p>
Return to the <a href="index.html">PCRE index page</a>.
Modified: code/trunk/doc/pcre.txt
===================================================================
--- code/trunk/doc/pcre.txt 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/pcre.txt 2009-04-11 14:34:02 UTC (rev 416)
@@ -28,7 +28,7 @@
mately with Perl 5.10, including support for UTF-8 encoded strings and
Unicode general category properties. However, UTF-8 and Unicode support
has to be explicitly enabled; it is not the default. The Unicode tables
- correspond to Unicode release 5.0.0.
+ correspond to Unicode release 5.1.
In addition to the Perl-compatible matching function, PCRE contains an
alternative matching function that matches the same compiled patterns
@@ -136,113 +136,114 @@
In order process UTF-8 strings, you must build PCRE to include UTF-8
support in the code, and, in addition, you must call pcre_compile()
- with the PCRE_UTF8 option flag. When you do this, both the pattern and
- any subject strings that are matched against it are treated as UTF-8
- strings instead of just strings of bytes.
+ with the PCRE_UTF8 option flag, or the pattern must start with the
+ sequence (*UTF8). When either of these is the case, both the pattern
+ and any subject strings that are matched against it are treated as
+ UTF-8 strings instead of just strings of bytes.
- If you compile PCRE with UTF-8 support, but do not use it at run time,
- the library will be a bit bigger, but the additional run time overhead
+ If you compile PCRE with UTF-8 support, but do not use it at run time,
+ the library will be a bit bigger, but the additional run time overhead
is limited to testing the PCRE_UTF8 flag occasionally, so should not be
very big.
If PCRE is built with Unicode character property support (which implies
- UTF-8 support), the escape sequences \p{..}, \P{..}, and \X are sup-
+ UTF-8 support), the escape sequences \p{..}, \P{..}, and \X are sup-
ported. The available properties that can be tested are limited to the
- general category properties such as Lu for an upper case letter or Nd
- for a decimal number, the Unicode script names such as Arabic or Han,
- and the derived properties Any and L&. A full list is given in the
+ general category properties such as Lu for an upper case letter or Nd
+ for a decimal number, the Unicode script names such as Arabic or Han,
+ and the derived properties Any and L&. A full list is given in the
pcrepattern documentation. Only the short names for properties are sup-
- ported. For example, \p{L} matches a letter. Its Perl synonym, \p{Let-
- ter}, is not supported. Furthermore, in Perl, many properties may
- optionally be prefixed by "Is", for compatibility with Perl 5.6. PCRE
+ ported. For example, \p{L} matches a letter. Its Perl synonym, \p{Let-
+ ter}, is not supported. Furthermore, in Perl, many properties may
+ optionally be prefixed by "Is", for compatibility with Perl 5.6. PCRE
does not support this.
Validity of UTF-8 strings
- When you set the PCRE_UTF8 flag, the strings passed as patterns and
+ When you set the PCRE_UTF8 flag, the strings passed as patterns and
subjects are (by default) checked for validity on entry to the relevant
- functions. From release 7.3 of PCRE, the check is according the rules
- of RFC 3629, which are themselves derived from the Unicode specifica-
- tion. Earlier releases of PCRE followed the rules of RFC 2279, which
- allows the full range of 31-bit values (0 to 0x7FFFFFFF). The current
+ functions. From release 7.3 of PCRE, the check is according the rules
+ of RFC 3629, which are themselves derived from the Unicode specifica-
+ tion. Earlier releases of PCRE followed the rules of RFC 2279, which
+ allows the full range of 31-bit values (0 to 0x7FFFFFFF). The current
check allows only values in the range U+0 to U+10FFFF, excluding U+D800
to U+DFFF.
- The excluded code points are the "Low Surrogate Area" of Unicode, of
- which the Unicode Standard says this: "The Low Surrogate Area does not
- contain any character assignments, consequently no character code
+ The excluded code points are the "Low Surrogate Area" of Unicode, of
+ which the Unicode Standard says this: "The Low Surrogate Area does not
+ contain any character assignments, consequently no character code
charts or namelists are provided for this area. Surrogates are reserved
- for use with UTF-16 and then must be used in pairs." The code points
- that are encoded by UTF-16 pairs are available as independent code
- points in the UTF-8 encoding. (In other words, the whole surrogate
+ for use with UTF-16 and then must be used in pairs." The code points
+ that are encoded by UTF-16 pairs are available as independent code
+ points in the UTF-8 encoding. (In other words, the whole surrogate
thing is a fudge for UTF-16 which unfortunately messes up UTF-8.)
- If an invalid UTF-8 string is passed to PCRE, an error return
+ If an invalid UTF-8 string is passed to PCRE, an error return
(PCRE_ERROR_BADUTF8) is given. In some situations, you may already know
that your strings are valid, and therefore want to skip these checks in
order to improve performance. If you set the PCRE_NO_UTF8_CHECK flag at
- compile time or at run time, PCRE assumes that the pattern or subject
- it is given (respectively) contains only valid UTF-8 codes. In this
+ compile time or at run time, PCRE assumes that the pattern or subject
+ it is given (respectively) contains only valid UTF-8 codes. In this
case, it does not diagnose an invalid UTF-8 string.
- If you pass an invalid UTF-8 string when PCRE_NO_UTF8_CHECK is set,
- what happens depends on why the string is invalid. If the string con-
+ If you pass an invalid UTF-8 string when PCRE_NO_UTF8_CHECK is set,
+ what happens depends on why the string is invalid. If the string con-
forms to the "old" definition of UTF-8 (RFC 2279), it is processed as a
- string of characters in the range 0 to 0x7FFFFFFF. In other words,
+ string of characters in the range 0 to 0x7FFFFFFF. In other words,
apart from the initial validity test, PCRE (when in UTF-8 mode) handles
- strings according to the more liberal rules of RFC 2279. However, if
- the string does not even conform to RFC 2279, the result is undefined.
+ strings according to the more liberal rules of RFC 2279. However, if
+ the string does not even conform to RFC 2279, the result is undefined.
Your program may crash.
- If you want to process strings of values in the full range 0 to
- 0x7FFFFFFF, encoded in a UTF-8-like manner as per the old RFC, you can
+ If you want to process strings of values in the full range 0 to
+ 0x7FFFFFFF, encoded in a UTF-8-like manner as per the old RFC, you can
set PCRE_NO_UTF8_CHECK to bypass the more restrictive test. However, in
this situation, you will have to apply your own validity check.
General comments about UTF-8 mode
- 1. An unbraced hexadecimal escape sequence (such as \xb3) matches a
+ 1. An unbraced hexadecimal escape sequence (such as \xb3) matches a
two-byte UTF-8 character if the value is greater than 127.
- 2. Octal numbers up to \777 are recognized, and match two-byte UTF-8
+ 2. Octal numbers up to \777 are recognized, and match two-byte UTF-8
characters for values greater than \177.
- 3. Repeat quantifiers apply to complete UTF-8 characters, not to indi-
+ 3. Repeat quantifiers apply to complete UTF-8 characters, not to indi-
vidual bytes, for example: \x{100}{3}.
- 4. The dot metacharacter matches one UTF-8 character instead of a sin-
+ 4. The dot metacharacter matches one UTF-8 character instead of a sin-
gle byte.
- 5. The escape sequence \C can be used to match a single byte in UTF-8
- mode, but its use can lead to some strange effects. This facility is
+ 5. The escape sequence \C can be used to match a single byte in UTF-8
+ mode, but its use can lead to some strange effects. This facility is
not available in the alternative matching function, pcre_dfa_exec().
- 6. The character escapes \b, \B, \d, \D, \s, \S, \w, and \W correctly
- test characters of any code value, but the characters that PCRE recog-
- nizes as digits, spaces, or word characters remain the same set as
+ 6. The character escapes \b, \B, \d, \D, \s, \S, \w, and \W correctly
+ test characters of any code value, but the characters that PCRE recog-
+ nizes as digits, spaces, or word characters remain the same set as
before, all with values less than 256. This remains true even when PCRE
- includes Unicode property support, because to do otherwise would slow
- down PCRE in many common cases. If you really want to test for a wider
- sense of, say, "digit", you must use Unicode property tests such as
- \p{Nd}. Note that this also applies to \b, because it is defined in
+ includes Unicode property support, because to do otherwise would slow
+ down PCRE in many common cases. If you really want to test for a wider
+ sense of, say, "digit", you must use Unicode property tests such as
+ \p{Nd}. Note that this also applies to \b, because it is defined in
terms of \w and \W.
- 7. Similarly, characters that match the POSIX named character classes
+ 7. Similarly, characters that match the POSIX named character classes
are all low-valued characters.
- 8. However, the Perl 5.10 horizontal and vertical whitespace matching
+ 8. However, the Perl 5.10 horizontal and vertical whitespace matching
escapes (\h, \H, \v, and \V) do match all the appropriate Unicode char-
acters.
- 9. Case-insensitive matching applies only to characters whose values
- are less than 128, unless PCRE is built with Unicode property support.
- Even when Unicode property support is available, PCRE still uses its
- own character tables when checking the case of low-valued characters,
- so as not to degrade performance. The Unicode property information is
+ 9. Case-insensitive matching applies only to characters whose values
+ are less than 128, unless PCRE is built with Unicode property support.
+ Even when Unicode property support is available, PCRE still uses its
+ own character tables when checking the case of low-valued characters,
+ so as not to degrade performance. The Unicode property information is
used only for characters with higher values. Even when Unicode property
support is available, PCRE supports case-insensitive matching only when
- there is a one-to-one mapping between a letter's cases. There are a
- small number of many-to-one mappings in Unicode; these are not sup-
+ there is a one-to-one mapping between a letter's cases. There are a
+ small number of many-to-one mappings in Unicode; these are not sup-
ported by PCRE.
@@ -252,14 +253,14 @@
University Computing Service
Cambridge CB2 3QH, England.
- Putting an actual email address here seems to have been a spam magnet,
- so I've taken it away. If you want to email me, use my two initials,
+ Putting an actual email address here seems to have been a spam magnet,
+ so I've taken it away. If you want to email me, use my two initials,
followed by the two digits 10, at the domain cam.ac.uk.
REVISION
- Last updated: 18 March 2009
+ Last updated: 11 April 2009
Copyright (c) 1997-2009 University of Cambridge.
------------------------------------------------------------------------------
@@ -1133,37 +1134,38 @@
The options argument contains various bit settings that affect the com-
pilation. It should be zero if no options are required. The available
- options are described below. Some of them, in particular, those that
- are compatible with Perl, can also be set and unset from within the
- pattern (see the detailed description in the pcrepattern documenta-
- tion). For these options, the contents of the options argument speci-
- fies their initial settings at the start of compilation and execution.
- The PCRE_ANCHORED and PCRE_NEWLINE_xxx options can be set at the time
- of matching as well as at compile time.
+ options are described below. Some of them (in particular, those that
+ are compatible with Perl, but also some others) can also be set and
+ unset from within the pattern (see the detailed description in the
+ pcrepattern documentation). For those options that can be different in
+ different parts of the pattern, the contents of the options argument
+ specifies their initial settings at the start of compilation and execu-
+ tion. The PCRE_ANCHORED and PCRE_NEWLINE_xxx options can be set at the
+ time of matching as well as at compile time.
If errptr is NULL, pcre_compile() returns NULL immediately. Otherwise,
- if compilation of a pattern fails, pcre_compile() returns NULL, and
+ if compilation of a pattern fails, pcre_compile() returns NULL, and
sets the variable pointed to by errptr to point to a textual error mes-
sage. This is a static string that is part of the library. You must not
try to free it. The offset from the start of the pattern to the charac-
ter where the error was discovered is placed in the variable pointed to
- by erroffset, which must not be NULL. If it is, an immediate error is
+ by erroffset, which must not be NULL. If it is, an immediate error is
given.
- If pcre_compile2() is used instead of pcre_compile(), and the error-
- codeptr argument is not NULL, a non-zero error code number is returned
- via this argument in the event of an error. This is in addition to the
+ If pcre_compile2() is used instead of pcre_compile(), and the error-
+ codeptr argument is not NULL, a non-zero error code number is returned
+ via this argument in the event of an error. This is in addition to the
textual error message. Error codes and messages are listed below.
- If the final argument, tableptr, is NULL, PCRE uses a default set of
- character tables that are built when PCRE is compiled, using the
- default C locale. Otherwise, tableptr must be an address that is the
- result of a call to pcre_maketables(). This value is stored with the
- compiled pattern, and used again by pcre_exec(), unless another table
+ If the final argument, tableptr, is NULL, PCRE uses a default set of
+ character tables that are built when PCRE is compiled, using the
+ default C locale. Otherwise, tableptr must be an address that is the
+ result of a call to pcre_maketables(). This value is stored with the
+ compiled pattern, and used again by pcre_exec(), unless another table
pointer is passed to it. For more discussion, see the section on locale
support below.
- This code fragment shows a typical straightforward call to pcre_com-
+ This code fragment shows a typical straightforward call to pcre_com-
pile():
pcre *re;
@@ -1176,137 +1178,137 @@
&erroffset, /* for error offset */
NULL); /* use default character tables */
- The following names for option bits are defined in the pcre.h header
+ The following names for option bits are defined in the pcre.h header
file:
PCRE_ANCHORED
If this bit is set, the pattern is forced to be "anchored", that is, it
- is constrained to match only at the first matching point in the string
- that is being searched (the "subject string"). This effect can also be
- achieved by appropriate constructs in the pattern itself, which is the
+ is constrained to match only at the first matching point in the string
+ that is being searched (the "subject string"). This effect can also be
+ achieved by appropriate constructs in the pattern itself, which is the
only way to do it in Perl.
PCRE_AUTO_CALLOUT
If this bit is set, pcre_compile() automatically inserts callout items,
- all with number 255, before each pattern item. For discussion of the
+ all with number 255, before each pattern item. For discussion of the
callout facility, see the pcrecallout documentation.
PCRE_BSR_ANYCRLF
PCRE_BSR_UNICODE
These options (which are mutually exclusive) control what the \R escape
- sequence matches. The choice is either to match only CR, LF, or CRLF,
+ sequence matches. The choice is either to match only CR, LF, or CRLF,
or to match any Unicode newline sequence. The default is specified when
PCRE is built. It can be overridden from within the pattern, or by set-
ting an option when a compiled pattern is matched.
PCRE_CASELESS
- If this bit is set, letters in the pattern match both upper and lower
- case letters. It is equivalent to Perl's /i option, and it can be
- changed within a pattern by a (?i) option setting. In UTF-8 mode, PCRE
- always understands the concept of case for characters whose values are
- less than 128, so caseless matching is always possible. For characters
- with higher values, the concept of case is supported if PCRE is com-
- piled with Unicode property support, but not otherwise. If you want to
- use caseless matching for characters 128 and above, you must ensure
- that PCRE is compiled with Unicode property support as well as with
+ If this bit is set, letters in the pattern match both upper and lower
+ case letters. It is equivalent to Perl's /i option, and it can be
+ changed within a pattern by a (?i) option setting. In UTF-8 mode, PCRE
+ always understands the concept of case for characters whose values are
+ less than 128, so caseless matching is always possible. For characters
+ with higher values, the concept of case is supported if PCRE is com-
+ piled with Unicode property support, but not otherwise. If you want to
+ use caseless matching for characters 128 and above, you must ensure
+ that PCRE is compiled with Unicode property support as well as with
UTF-8 support.
PCRE_DOLLAR_ENDONLY
- If this bit is set, a dollar metacharacter in the pattern matches only
- at the end of the subject string. Without this option, a dollar also
- matches immediately before a newline at the end of the string (but not
- before any other newlines). The PCRE_DOLLAR_ENDONLY option is ignored
- if PCRE_MULTILINE is set. There is no equivalent to this option in
+ If this bit is set, a dollar metacharacter in the pattern matches only
+ at the end of the subject string. Without this option, a dollar also
+ matches immediately before a newline at the end of the string (but not
+ before any other newlines). The PCRE_DOLLAR_ENDONLY option is ignored
+ if PCRE_MULTILINE is set. There is no equivalent to this option in
Perl, and no way to set it within a pattern.
PCRE_DOTALL
If this bit is set, a dot metacharater in the pattern matches all char-
- acters, including those that indicate newline. Without it, a dot does
- not match when the current position is at a newline. This option is
- equivalent to Perl's /s option, and it can be changed within a pattern
- by a (?s) option setting. A negative class such as [^a] always matches
+ acters, including those that indicate newline. Without it, a dot does
+ not match when the current position is at a newline. This option is
+ equivalent to Perl's /s option, and it can be changed within a pattern
+ by a (?s) option setting. A negative class such as [^a] always matches
newline characters, independent of the setting of this option.
PCRE_DUPNAMES
- If this bit is set, names used to identify capturing subpatterns need
+ If this bit is set, names used to identify capturing subpatterns need
not be unique. This can be helpful for certain types of pattern when it
- is known that only one instance of the named subpattern can ever be
- matched. There are more details of named subpatterns below; see also
+ is known that only one instance of the named subpattern can ever be
+ matched. There are more details of named subpatterns below; see also
the pcrepattern documentation.
PCRE_EXTENDED
- If this bit is set, whitespace data characters in the pattern are
+ If this bit is set, whitespace data characters in the pattern are
totally ignored except when escaped or inside a character class. White-
space does not include the VT character (code 11). In addition, charac-
ters between an unescaped # outside a character class and the next new-
- line, inclusive, are also ignored. This is equivalent to Perl's /x
- option, and it can be changed within a pattern by a (?x) option set-
+ line, inclusive, are also ignored. This is equivalent to Perl's /x
+ option, and it can be changed within a pattern by a (?x) option set-
ting.
- This option makes it possible to include comments inside complicated
- patterns. Note, however, that this applies only to data characters.
- Whitespace characters may never appear within special character
- sequences in a pattern, for example within the sequence (?( which
+ This option makes it possible to include comments inside complicated
+ patterns. Note, however, that this applies only to data characters.
+ Whitespace characters may never appear within special character
+ sequences in a pattern, for example within the sequence (?( which
introduces a conditional subpattern.
PCRE_EXTRA
- This option was invented in order to turn on additional functionality
- of PCRE that is incompatible with Perl, but it is currently of very
- little use. When set, any backslash in a pattern that is followed by a
- letter that has no special meaning causes an error, thus reserving
- these combinations for future expansion. By default, as in Perl, a
- backslash followed by a letter with no special meaning is treated as a
- literal. (Perl can, however, be persuaded to give a warning for this.)
- There are at present no other features controlled by this option. It
+ This option was invented in order to turn on additional functionality
+ of PCRE that is incompatible with Perl, but it is currently of very
+ little use. When set, any backslash in a pattern that is followed by a
+ letter that has no special meaning causes an error, thus reserving
+ these combinations for future expansion. By default, as in Perl, a
+ backslash followed by a letter with no special meaning is treated as a
+ literal. (Perl can, however, be persuaded to give a warning for this.)
+ There are at present no other features controlled by this option. It
can also be set by a (?X) option setting within a pattern.
PCRE_FIRSTLINE
- If this option is set, an unanchored pattern is required to match
- before or at the first newline in the subject string, though the
+ If this option is set, an unanchored pattern is required to match
+ before or at the first newline in the subject string, though the
matched text may continue over the newline.
PCRE_JAVASCRIPT_COMPAT
If this option is set, PCRE's behaviour is changed in some ways so that
- it is compatible with JavaScript rather than Perl. The changes are as
+ it is compatible with JavaScript rather than Perl. The changes are as
follows:
- (1) A lone closing square bracket in a pattern causes a compile-time
- error, because this is illegal in JavaScript (by default it is treated
+ (1) A lone closing square bracket in a pattern causes a compile-time
+ error, because this is illegal in JavaScript (by default it is treated
as a data character). Thus, the pattern AB]CD becomes illegal when this
option is set.
- (2) At run time, a back reference to an unset subpattern group matches
- an empty string (by default this causes the current matching alterna-
- tive to fail). A pattern such as (\1)(a) succeeds when this option is
- set (assuming it can find an "a" in the subject), whereas it fails by
+ (2) At run time, a back reference to an unset subpattern group matches
+ an empty string (by default this causes the current matching alterna-
+ tive to fail). A pattern such as (\1)(a) succeeds when this option is
+ set (assuming it can find an "a" in the subject), whereas it fails by
default, for Perl compatibility.
PCRE_MULTILINE
- By default, PCRE treats the subject string as consisting of a single
- line of characters (even if it actually contains newlines). The "start
- of line" metacharacter (^) matches only at the start of the string,
- while the "end of line" metacharacter ($) matches only at the end of
+ By default, PCRE treats the subject string as consisting of a single
+ line of characters (even if it actually contains newlines). The "start
+ of line" metacharacter (^) matches only at the start of the string,
+ while the "end of line" metacharacter ($) matches only at the end of
the string, or before a terminating newline (unless PCRE_DOLLAR_ENDONLY
is set). This is the same as Perl.
- When PCRE_MULTILINE it is set, the "start of line" and "end of line"
- constructs match immediately following or immediately before internal
- newlines in the subject string, respectively, as well as at the very
- start and end. This is equivalent to Perl's /m option, and it can be
+ When PCRE_MULTILINE it is set, the "start of line" and "end of line"
+ constructs match immediately following or immediately before internal
+ newlines in the subject string, respectively, as well as at the very
+ start and end. This is equivalent to Perl's /m option, and it can be
changed within a pattern by a (?m) option setting. If there are no new-
- lines in a subject string, or no occurrences of ^ or $ in a pattern,
+ lines in a subject string, or no occurrences of ^ or $ in a pattern,
setting PCRE_MULTILINE has no effect.
PCRE_NEWLINE_CR
@@ -1315,32 +1317,32 @@
PCRE_NEWLINE_ANYCRLF
PCRE_NEWLINE_ANY
- These options override the default newline definition that was chosen
- when PCRE was built. Setting the first or the second specifies that a
- newline is indicated by a single character (CR or LF, respectively).
- Setting PCRE_NEWLINE_CRLF specifies that a newline is indicated by the
- two-character CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies
+ These options override the default newline definition that was chosen
+ when PCRE was built. Setting the first or the second specifies that a
+ newline is indicated by a single character (CR or LF, respectively).
+ Setting PCRE_NEWLINE_CRLF specifies that a newline is indicated by the
+ two-character CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies
that any of the three preceding sequences should be recognized. Setting
- PCRE_NEWLINE_ANY specifies that any Unicode newline sequence should be
+ PCRE_NEWLINE_ANY specifies that any Unicode newline sequence should be
recognized. The Unicode newline sequences are the three just mentioned,
- plus the single characters VT (vertical tab, U+000B), FF (formfeed,
- U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
- (paragraph separator, U+2029). The last two are recognized only in
+ plus the single characters VT (vertical tab, U+000B), FF (formfeed,
+ U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
+ (paragraph separator, U+2029). The last two are recognized only in
UTF-8 mode.
- The newline setting in the options word uses three bits that are
+ The newline setting in the options word uses three bits that are
treated as a number, giving eight possibilities. Currently only six are
- used (default plus the five values above). This means that if you set
- more than one newline option, the combination may or may not be sensi-
+ used (default plus the five values above). This means that if you set
+ more than one newline option, the combination may or may not be sensi-
ble. For example, PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to
- PCRE_NEWLINE_CRLF, but other combinations may yield unused numbers and
+ PCRE_NEWLINE_CRLF, but other combinations may yield unused numbers and
cause an error.
- The only time that a line break is specially recognized when compiling
- a pattern is if PCRE_EXTENDED is set, and an unescaped # outside a
- character class is encountered. This indicates a comment that lasts
- until after the next line break sequence. In other circumstances, line
- break sequences are treated as literal data, except that in
+ The only time that a line break is specially recognized when compiling
+ a pattern is if PCRE_EXTENDED is set, and an unescaped # outside a
+ character class is encountered. This indicates a comment that lasts
+ until after the next line break sequence. In other circumstances, line
+ break sequences are treated as literal data, except that in
PCRE_EXTENDED mode, both CR and LF are treated as whitespace characters
and are therefore ignored.
@@ -1350,46 +1352,46 @@
PCRE_NO_AUTO_CAPTURE
If this option is set, it disables the use of numbered capturing paren-
- theses in the pattern. Any opening parenthesis that is not followed by
- ? behaves as if it were followed by ?: but named parentheses can still
- be used for capturing (and they acquire numbers in the usual way).
+ theses in the pattern. Any opening parenthesis that is not followed by
+ ? behaves as if it were followed by ?: but named parentheses can still
+ be used for capturing (and they acquire numbers in the usual way).
There is no equivalent of this option in Perl.
PCRE_UNGREEDY
- This option inverts the "greediness" of the quantifiers so that they
- are not greedy by default, but become greedy if followed by "?". It is
- not compatible with Perl. It can also be set by a (?U) option setting
+ This option inverts the "greediness" of the quantifiers so that they
+ are not greedy by default, but become greedy if followed by "?". It is
+ not compatible with Perl. It can also be set by a (?U) option setting
within the pattern.
PCRE_UTF8
- This option causes PCRE to regard both the pattern and the subject as
- strings of UTF-8 characters instead of single-byte character strings.
- However, it is available only when PCRE is built to include UTF-8 sup-
- port. If not, the use of this option provokes an error. Details of how
- this option changes the behaviour of PCRE are given in the section on
+ This option causes PCRE to regard both the pattern and the subject as
+ strings of UTF-8 characters instead of single-byte character strings.
+ However, it is available only when PCRE is built to include UTF-8 sup-
+ port. If not, the use of this option provokes an error. Details of how
+ this option changes the behaviour of PCRE are given in the section on
UTF-8 support in the main pcre page.
PCRE_NO_UTF8_CHECK
When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is
- automatically checked. There is a discussion about the validity of
- UTF-8 strings in the main pcre page. If an invalid UTF-8 sequence of
- bytes is found, pcre_compile() returns an error. If you already know
+ automatically checked. There is a discussion about the validity of
+ UTF-8 strings in the main pcre page. If an invalid UTF-8 sequence of
+ bytes is found, pcre_compile() returns an error. If you already know
that your pattern is valid, and you want to skip this check for perfor-
- mance reasons, you can set the PCRE_NO_UTF8_CHECK option. When it is
- set, the effect of passing an invalid UTF-8 string as a pattern is
- undefined. It may cause your program to crash. Note that this option
- can also be passed to pcre_exec() and pcre_dfa_exec(), to suppress the
+ mance reasons, you can set the PCRE_NO_UTF8_CHECK option. When it is
+ set, the effect of passing an invalid UTF-8 string as a pattern is
+ undefined. It may cause your program to crash. Note that this option
+ can also be passed to pcre_exec() and pcre_dfa_exec(), to suppress the
UTF-8 validity checking of subject strings.
COMPILATION ERROR CODES
- The following table lists the error codes than may be returned by
- pcre_compile2(), along with the error messages that may be returned by
- both compiling functions. As PCRE has developed, some error codes have
+ The following table lists the error codes than may be returned by
+ pcre_compile2(), along with the error messages that may be returned by
+ both compiling functions. As PCRE has developed, some error codes have
fallen out of use. To avoid confusion, they have not been re-used.
0 no error
@@ -1445,7 +1447,7 @@
50 [this code is not in use]
51 octal value is greater than \377 (not in UTF-8 mode)
52 internal error: overran compiling workspace
- 53 internal error: previously-checked referenced subpattern not
+ 53 internal error: previously-checked referenced subpattern not
found
54 DEFINE group contains more than one branch
55 repeating a DEFINE group is not allowed
@@ -1460,7 +1462,7 @@
63 digit expected after (?+
64 ] is an invalid data character in JavaScript compatibility mode
- The numbers 32 and 10000 in errors 48 and 49 are defaults; different
+ The numbers 32 and 10000 in errors 48 and 49 are defaults; different
values may be used if the limits were changed when PCRE was built.
@@ -1469,32 +1471,32 @@
pcre_extra *pcre_study(const pcre *code, int options
const char **errptr);
- If a compiled pattern is going to be used several times, it is worth
+ If a compiled pattern is going to be used several times, it is worth
spending more time analyzing it in order to speed up the time taken for
- matching. The function pcre_study() takes a pointer to a compiled pat-
+ matching. The function pcre_study() takes a pointer to a compiled pat-
tern as its first argument. If studying the pattern produces additional
- information that will help speed up matching, pcre_study() returns a
- pointer to a pcre_extra block, in which the study_data field points to
+ information that will help speed up matching, pcre_study() returns a
+ pointer to a pcre_extra block, in which the study_data field points to
the results of the study.
The returned value from pcre_study() can be passed directly to
- pcre_exec(). However, a pcre_extra block also contains other fields
- that can be set by the caller before the block is passed; these are
+ pcre_exec(). However, a pcre_extra block also contains other fields
+ that can be set by the caller before the block is passed; these are
described below in the section on matching a pattern.
- If studying the pattern does not produce any additional information
+ If studying the pattern does not produce any additional information
pcre_study() returns NULL. In that circumstance, if the calling program
- wants to pass any of the other fields to pcre_exec(), it must set up
+ wants to pass any of the other fields to pcre_exec(), it must set up
its own pcre_extra block.
- The second argument of pcre_study() contains option bits. At present,
+ The second argument of pcre_study() contains option bits. At present,
no options are defined, and this argument should always be zero.
- The third argument for pcre_study() is a pointer for an error message.
- If studying succeeds (even if no data is returned), the variable it
- points to is set to NULL. Otherwise it is set to point to a textual
+ The third argument for pcre_study() is a pointer for an error message.
+ If studying succeeds (even if no data is returned), the variable it
+ points to is set to NULL. Otherwise it is set to point to a textual
error message. This is a static string that is part of the library. You
- must not try to free it. You should test the error pointer for NULL
+ must not try to free it. You should test the error pointer for NULL
after calling pcre_study(), to be sure that it has run successfully.
This is a typical call to pcre_study():
@@ -1506,62 +1508,62 @@
&error); /* set to NULL or points to a message */
At present, studying a pattern is useful only for non-anchored patterns
- that do not have a single fixed starting character. A bitmap of possi-
+ that do not have a single fixed starting character. A bitmap of possi-
ble starting bytes is created.
LOCALE SUPPORT
- PCRE handles caseless matching, and determines whether characters are
- letters, digits, or whatever, by reference to a set of tables, indexed
- by character value. When running in UTF-8 mode, this applies only to
- characters with codes less than 128. Higher-valued codes never match
- escapes such as \w or \d, but can be tested with \p if PCRE is built
- with Unicode character property support. The use of locales with Uni-
- code is discouraged. If you are handling characters with codes greater
- than 128, you should either use UTF-8 and Unicode, or use locales, but
+ PCRE handles caseless matching, and determines whether characters are
+ letters, digits, or whatever, by reference to a set of tables, indexed
+ by character value. When running in UTF-8 mode, this applies only to
+ characters with codes less than 128. Higher-valued codes never match
+ escapes such as \w or \d, but can be tested with \p if PCRE is built
+ with Unicode character property support. The use of locales with Uni-
+ code is discouraged. If you are handling characters with codes greater
+ than 128, you should either use UTF-8 and Unicode, or use locales, but
not try to mix the two.
- PCRE contains an internal set of tables that are used when the final
- argument of pcre_compile() is NULL. These are sufficient for many
+ PCRE contains an internal set of tables that are used when the final
+ argument of pcre_compile() is NULL. These are sufficient for many
applications. Normally, the internal tables recognize only ASCII char-
acters. However, when PCRE is built, it is possible to cause the inter-
nal tables to be rebuilt in the default "C" locale of the local system,
which may cause them to be different.
- The internal tables can always be overridden by tables supplied by the
+ The internal tables can always be overridden by tables supplied by the
application that calls PCRE. These may be created in a different locale
- from the default. As more and more applications change to using Uni-
+ from the default. As more and more applications change to using Uni-
code, the need for this locale support is expected to die away.
- External tables are built by calling the pcre_maketables() function,
- which has no arguments, in the relevant locale. The result can then be
- passed to pcre_compile() or pcre_exec() as often as necessary. For
- example, to build and use tables that are appropriate for the French
- locale (where accented characters with values greater than 128 are
+ External tables are built by calling the pcre_maketables() function,
+ which has no arguments, in the relevant locale. The result can then be
+ passed to pcre_compile() or pcre_exec() as often as necessary. For
+ example, to build and use tables that are appropriate for the French
+ locale (where accented characters with values greater than 128 are
treated as letters), the following code could be used:
setlocale(LC_CTYPE, "fr_FR");
tables = pcre_maketables();
re = pcre_compile(..., tables);
- The locale name "fr_FR" is used on Linux and other Unix-like systems;
+ The locale name "fr_FR" is used on Linux and other Unix-like systems;
if you are using Windows, the name for the French locale is "french".
- When pcre_maketables() runs, the tables are built in memory that is
- obtained via pcre_malloc. It is the caller's responsibility to ensure
- that the memory containing the tables remains available for as long as
+ When pcre_maketables() runs, the tables are built in memory that is
+ obtained via pcre_malloc. It is the caller's responsibility to ensure
+ that the memory containing the tables remains available for as long as
it is needed.
The pointer that is passed to pcre_compile() is saved with the compiled
- pattern, and the same tables are used via this pointer by pcre_study()
+ pattern, and the same tables are used via this pointer by pcre_study()
and normally also by pcre_exec(). Thus, by default, for any single pat-
tern, compilation, studying and matching all happen in the same locale,
but different patterns can be compiled in different locales.
- It is possible to pass a table pointer or NULL (indicating the use of
- the internal tables) to pcre_exec(). Although not intended for this
- purpose, this facility could be used to match a pattern in a different
+ It is possible to pass a table pointer or NULL (indicating the use of
+ the internal tables) to pcre_exec(). Although not intended for this
+ purpose, this facility could be used to match a pattern in a different
locale from the one in which it was compiled. Passing table pointers at
run time is discussed below in the section on matching a pattern.
@@ -1571,15 +1573,15 @@
int pcre_fullinfo(const pcre *code, const pcre_extra *extra,
int what, void *where);
- The pcre_fullinfo() function returns information about a compiled pat-
+ The pcre_fullinfo() function returns information about a compiled pat-
tern. It replaces the obsolete pcre_info() function, which is neverthe-
less retained for backwards compability (and is documented below).
- The first argument for pcre_fullinfo() is a pointer to the compiled
- pattern. The second argument is the result of pcre_study(), or NULL if
- the pattern was not studied. The third argument specifies which piece
- of information is required, and the fourth argument is a pointer to a
- variable to receive the data. The yield of the function is zero for
+ The first argument for pcre_fullinfo() is a pointer to the compiled
+ pattern. The second argument is the result of pcre_study(), or NULL if
+ the pattern was not studied. The third argument specifies which piece
+ of information is required, and the fourth argument is a pointer to a
+ variable to receive the data. The yield of the function is zero for
success, or one of the following negative numbers:
PCRE_ERROR_NULL the argument code was NULL
@@ -1587,9 +1589,9 @@
PCRE_ERROR_BADMAGIC the "magic number" was not found
PCRE_ERROR_BADOPTION the value of what was invalid
- The "magic number" is placed at the start of each compiled pattern as
- an simple check against passing an arbitrary memory pointer. Here is a
- typical call of pcre_fullinfo(), to obtain the length of the compiled
+ The "magic number" is placed at the start of each compiled pattern as
+ an simple check against passing an arbitrary memory pointer. Here is a
+ typical call of pcre_fullinfo(), to obtain the length of the compiled
pattern:
int rc;
@@ -1600,76 +1602,76 @@
PCRE_INFO_SIZE, /* what is required */
&length); /* where to put the data */
- The possible values for the third argument are defined in pcre.h, and
+ The possible values for the third argument are defined in pcre.h, and
are as follows:
PCRE_INFO_BACKREFMAX
- Return the number of the highest back reference in the pattern. The
- fourth argument should point to an int variable. Zero is returned if
+ Return the number of the highest back reference in the pattern. The
+ fourth argument should point to an int variable. Zero is returned if
there are no back references.
PCRE_INFO_CAPTURECOUNT
- Return the number of capturing subpatterns in the pattern. The fourth
+ Return the number of capturing subpatterns in the pattern. The fourth
argument should point to an int variable.
PCRE_INFO_DEFAULT_TABLES
- Return a pointer to the internal default character tables within PCRE.
- The fourth argument should point to an unsigned char * variable. This
+ Return a pointer to the internal default character tables within PCRE.
+ The fourth argument should point to an unsigned char * variable. This
information call is provided for internal use by the pcre_study() func-
- tion. External callers can cause PCRE to use its internal tables by
+ tion. External callers can cause PCRE to use its internal tables by
passing a NULL table pointer.
PCRE_INFO_FIRSTBYTE
- Return information about the first byte of any matched string, for a
- non-anchored pattern. The fourth argument should point to an int vari-
- able. (This option used to be called PCRE_INFO_FIRSTCHAR; the old name
+ Return information about the first byte of any matched string, for a
+ non-anchored pattern. The fourth argument should point to an int vari-
+ able. (This option used to be called PCRE_INFO_FIRSTCHAR; the old name
is still recognized for backwards compatibility.)
- If there is a fixed first byte, for example, from a pattern such as
+ If there is a fixed first byte, for example, from a pattern such as
(cat|cow|coyote), its value is returned. Otherwise, if either
- (a) the pattern was compiled with the PCRE_MULTILINE option, and every
+ (a) the pattern was compiled with the PCRE_MULTILINE option, and every
branch starts with "^", or
(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not
set (if it were set, the pattern would be anchored),
- -1 is returned, indicating that the pattern matches only at the start
- of a subject string or after any newline within the string. Otherwise
+ -1 is returned, indicating that the pattern matches only at the start
+ of a subject string or after any newline within the string. Otherwise
-2 is returned. For anchored patterns, -2 is returned.
PCRE_INFO_FIRSTTABLE
- If the pattern was studied, and this resulted in the construction of a
+ If the pattern was studied, and this resulted in the construction of a
256-bit table indicating a fixed set of bytes for the first byte in any
- matching string, a pointer to the table is returned. Otherwise NULL is
- returned. The fourth argument should point to an unsigned char * vari-
+ matching string, a pointer to the table is returned. Otherwise NULL is
+ returned. The fourth argument should point to an unsigned char * vari-
able.
PCRE_INFO_HASCRORLF
- Return 1 if the pattern contains any explicit matches for CR or LF
- characters, otherwise 0. The fourth argument should point to an int
- variable. An explicit match is either a literal CR or LF character, or
+ Return 1 if the pattern contains any explicit matches for CR or LF
+ characters, otherwise 0. The fourth argument should point to an int
+ variable. An explicit match is either a literal CR or LF character, or
\r or \n.
PCRE_INFO_JCHANGED
- Return 1 if the (?J) or (?-J) option setting is used in the pattern,
- otherwise 0. The fourth argument should point to an int variable. (?J)
+ Return 1 if the (?J) or (?-J) option setting is used in the pattern,
+ otherwise 0. The fourth argument should point to an int variable. (?J)
and (?-J) set and unset the local PCRE_DUPNAMES option, respectively.
PCRE_INFO_LASTLITERAL
- Return the value of the rightmost literal byte that must exist in any
- matched string, other than at its start, if such a byte has been
+ Return the value of the rightmost literal byte that must exist in any
+ matched string, other than at its start, if such a byte has been
recorded. The fourth argument should point to an int variable. If there
- is no such byte, -1 is returned. For anchored patterns, a last literal
- byte is recorded only if it follows something of variable length. For
+ is no such byte, -1 is returned. For anchored patterns, a last literal
+ byte is recorded only if it follows something of variable length. For
example, for the pattern /^a\d+z\d+/ the returned value is "z", but for
/^a\dz\d/ the returned value is -1.
@@ -1677,34 +1679,34 @@
PCRE_INFO_NAMEENTRYSIZE
PCRE_INFO_NAMETABLE
- PCRE supports the use of named as well as numbered capturing parenthe-
- ses. The names are just an additional way of identifying the parenthe-
+ PCRE supports the use of named as well as numbered capturing parenthe-
+ ses. The names are just an additional way of identifying the parenthe-
ses, which still acquire numbers. Several convenience functions such as
- pcre_get_named_substring() are provided for extracting captured sub-
- strings by name. It is also possible to extract the data directly, by
- first converting the name to a number in order to access the correct
+ pcre_get_named_substring() are provided for extracting captured sub-
+ strings by name. It is also possible to extract the data directly, by
+ first converting the name to a number in order to access the correct
pointers in the output vector (described with pcre_exec() below). To do
- the conversion, you need to use the name-to-number map, which is
+ the conversion, you need to use the name-to-number map, which is
described by these three values.
The map consists of a number of fixed-size entries. PCRE_INFO_NAMECOUNT
gives the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size
- of each entry; both of these return an int value. The entry size
- depends on the length of the longest name. PCRE_INFO_NAMETABLE returns
- a pointer to the first entry of the table (a pointer to char). The
+ of each entry; both of these return an int value. The entry size
+ depends on the length of the longest name. PCRE_INFO_NAMETABLE returns
+ a pointer to the first entry of the table (a pointer to char). The
first two bytes of each entry are the number of the capturing parenthe-
- sis, most significant byte first. The rest of the entry is the corre-
- sponding name, zero terminated. The names are in alphabetical order.
+ sis, most significant byte first. The rest of the entry is the corre-
+ sponding name, zero terminated. The names are in alphabetical order.
When PCRE_DUPNAMES is set, duplicate names are in order of their paren-
- theses numbers. For example, consider the following pattern (assume
- PCRE_EXTENDED is set, so white space - including newlines - is
+ theses numbers. For example, consider the following pattern (assume
+ PCRE_EXTENDED is set, so white space - including newlines - is
ignored):
(?<date> (?<year>(\d\d)?\d\d) -
(?<month>\d\d) - (?<day>\d\d) )
- There are four named subpatterns, so the table has four entries, and
- each entry in the table is eight bytes long. The table is as follows,
+ There are four named subpatterns, so the table has four entries, and
+ each entry in the table is eight bytes long. The table is as follows,
with non-printing bytes shows in hexadecimal, and undefined bytes shown
as ??:
@@ -1713,29 +1715,29 @@
00 04 m o n t h 00
00 02 y e a r 00 ??
- When writing code to extract data from named subpatterns using the
- name-to-number map, remember that the length of the entries is likely
+ When writing code to extract data from named subpatterns using the
+ name-to-number map, remember that the length of the entries is likely
to be different for each compiled pattern.
PCRE_INFO_OKPARTIAL
- Return 1 if the pattern can be used for partial matching, otherwise 0.
- The fourth argument should point to an int variable. The pcrepartial
- documentation lists the restrictions that apply to patterns when par-
+ Return 1 if the pattern can be used for partial matching, otherwise 0.
+ The fourth argument should point to an int variable. The pcrepartial
+ documentation lists the restrictions that apply to patterns when par-
tial matching is used.
PCRE_INFO_OPTIONS
- Return a copy of the options with which the pattern was compiled. The
- fourth argument should point to an unsigned long int variable. These
+ Return a copy of the options with which the pattern was compiled. The
+ fourth argument should point to an unsigned long int variable. These
option bits are those specified in the call to pcre_compile(), modified
by any top-level option settings at the start of the pattern itself. In
- other words, they are the options that will be in force when matching
- starts. For example, if the pattern /(?im)abc(?-i)d/ is compiled with
- the PCRE_EXTENDED option, the result is PCRE_CASELESS, PCRE_MULTILINE,
+ other words, they are the options that will be in force when matching
+ starts. For example, if the pattern /(?im)abc(?-i)d/ is compiled with
+ the PCRE_EXTENDED option, the result is PCRE_CASELESS, PCRE_MULTILINE,
and PCRE_EXTENDED.
- A pattern is automatically anchored by PCRE if all of its top-level
+ A pattern is automatically anchored by PCRE if all of its top-level
alternatives begin with one of the following:
^ unless PCRE_MULTILINE is set
@@ -1749,7 +1751,7 @@
PCRE_INFO_SIZE
- Return the size of the compiled pattern, that is, the value that was
+ Return the size of the compiled pattern, that is, the value that was
passed as the argument to pcre_malloc() when PCRE was getting memory in
which to place the compiled data. The fourth argument should point to a
size_t variable.
@@ -1757,9 +1759,9 @@
PCRE_INFO_STUDYSIZE
Return the size of the data block pointed to by the study_data field in
- a pcre_extra block. That is, it is the value that was passed to
+ a pcre_extra block. That is, it is the value that was passed to
pcre_malloc() when PCRE was getting memory into which to place the data
- created by pcre_study(). The fourth argument should point to a size_t
+ created by pcre_study(). The fourth argument should point to a size_t
variable.
@@ -1767,21 +1769,21 @@
int pcre_info(const pcre *code, int *optptr, int *firstcharptr);
- The pcre_info() function is now obsolete because its interface is too
- restrictive to return all the available data about a compiled pattern.
- New programs should use pcre_fullinfo() instead. The yield of
- pcre_info() is the number of capturing subpatterns, or one of the fol-
+ The pcre_info() function is now obsolete because its interface is too
+ restrictive to return all the available data about a compiled pattern.
+ New programs should use pcre_fullinfo() instead. The yield of
+ pcre_info() is the number of capturing subpatterns, or one of the fol-
lowing negative numbers:
PCRE_ERROR_NULL the argument code was NULL
PCRE_ERROR_BADMAGIC the "magic number" was not found
- If the optptr argument is not NULL, a copy of the options with which
- the pattern was compiled is placed in the integer it points to (see
+ If the optptr argument is not NULL, a copy of the options with which
+ the pattern was compiled is placed in the integer it points to (see
PCRE_INFO_OPTIONS above).
- If the pattern is not anchored and the firstcharptr argument is not
- NULL, it is used to pass back information about the first character of
+ If the pattern is not anchored and the firstcharptr argument is not
+ NULL, it is used to pass back information about the first character of
any matched string (see PCRE_INFO_FIRSTBYTE above).
@@ -1789,21 +1791,21 @@
int pcre_refcount(pcre *code, int adjust);
- The pcre_refcount() function is used to maintain a reference count in
+ The pcre_refcount() function is used to maintain a reference count in
the data block that contains a compiled pattern. It is provided for the
- benefit of applications that operate in an object-oriented manner,
+ benefit of applications that operate in an object-oriented manner,
where different parts of the application may be using the same compiled
pattern, but you want to free the block when they are all done.
When a pattern is compiled, the reference count field is initialized to
- zero. It is changed only by calling this function, whose action is to
- add the adjust value (which may be positive or negative) to it. The
+ zero. It is changed only by calling this function, whose action is to
+ add the adjust value (which may be positive or negative) to it. The
yield of the function is the new value. However, the value of the count
- is constrained to lie between 0 and 65535, inclusive. If the new value
+ is constrained to lie between 0 and 65535, inclusive. If the new value
is outside these limits, it is forced to the appropriate limit value.
- Except when it is zero, the reference count is not correctly preserved
- if a pattern is compiled on one host and then transferred to a host
+ Except when it is zero, the reference count is not correctly preserved
+ if a pattern is compiled on one host and then transferred to a host
whose byte-order is different. (This seems a highly unlikely scenario.)
@@ -1813,18 +1815,18 @@
const char *subject, int length, int startoffset,
int options, int *ovector, int ovecsize);
- The function pcre_exec() is called to match a subject string against a
- compiled pattern, which is passed in the code argument. If the pattern
+ The function pcre_exec() is called to match a subject string against a
+ compiled pattern, which is passed in the code argument. If the pattern
has been studied, the result of the study should be passed in the extra
- argument. This function is the main matching facility of the library,
+ argument. This function is the main matching facility of the library,
and it operates in a Perl-like manner. For specialist use there is also
- an alternative matching function, which is described below in the sec-
+ an alternative matching function, which is described below in the sec-
tion about the pcre_dfa_exec() function.
- In most applications, the pattern will have been compiled (and option-
- ally studied) in the same process that calls pcre_exec(). However, it
+ In most applications, the pattern will have been compiled (and option-
+ ally studied) in the same process that calls pcre_exec(). However, it
is possible to save compiled patterns and study data, and then use them
- later in different processes, possibly even on different hosts. For a
+ later in different processes, possibly even on different hosts. For a
discussion about this, see the pcreprecompile documentation.
Here is an example of a simple call to pcre_exec():
@@ -1843,10 +1845,10 @@
Extra data for pcre_exec()
- If the extra argument is not NULL, it must point to a pcre_extra data
- block. The pcre_study() function returns such a block (when it doesn't
- return NULL), but you can also create one for yourself, and pass addi-
- tional information in it. The pcre_extra block contains the following
+ If the extra argument is not NULL, it must point to a pcre_extra data
+ block. The pcre_study() function returns such a block (when it doesn't
+ return NULL), but you can also create one for yourself, and pass addi-
+ tional information in it. The pcre_extra block contains the following
fields (not necessarily in this order):
unsigned long int flags;
@@ -1856,7 +1858,7 @@
void *callout_data;
const unsigned char *tables;
- The flags field is a bitmap that specifies which of the other fields
+ The flags field is a bitmap that specifies which of the other fields
are set. The flag bits are:
PCRE_EXTRA_STUDY_DATA
@@ -1865,83 +1867,83 @@
PCRE_EXTRA_CALLOUT_DATA
PCRE_EXTRA_TABLES
- Other flag bits should be set to zero. The study_data field is set in
- the pcre_extra block that is returned by pcre_study(), together with
+ Other flag bits should be set to zero. The study_data field is set in
+ the pcre_extra block that is returned by pcre_study(), together with
the appropriate flag bit. You should not set this yourself, but you may
- add to the block by setting the other fields and their corresponding
+ add to the block by setting the other fields and their corresponding
flag bits.
The match_limit field provides a means of preventing PCRE from using up
- a vast amount of resources when running patterns that are not going to
- match, but which have a very large number of possibilities in their
- search trees. The classic example is the use of nested unlimited
+ a vast amount of resources when running patterns that are not going to
+ match, but which have a very large number of possibilities in their
+ search trees. The classic example is the use of nested unlimited
repeats.
- Internally, PCRE uses a function called match() which it calls repeat-
- edly (sometimes recursively). The limit set by match_limit is imposed
- on the number of times this function is called during a match, which
- has the effect of limiting the amount of backtracking that can take
+ Internally, PCRE uses a function called match() which it calls repeat-
+ edly (sometimes recursively). The limit set by match_limit is imposed
+ on the number of times this function is called during a match, which
+ has the effect of limiting the amount of backtracking that can take
place. For patterns that are not anchored, the count restarts from zero
for each position in the subject string.
- The default value for the limit can be set when PCRE is built; the
- default default is 10 million, which handles all but the most extreme
- cases. You can override the default by suppling pcre_exec() with a
- pcre_extra block in which match_limit is set, and
- PCRE_EXTRA_MATCH_LIMIT is set in the flags field. If the limit is
+ The default value for the limit can be set when PCRE is built; the
+ default default is 10 million, which handles all but the most extreme
+ cases. You can override the default by suppling pcre_exec() with a
+ pcre_extra block in which match_limit is set, and
+ PCRE_EXTRA_MATCH_LIMIT is set in the flags field. If the limit is
exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
- The match_limit_recursion field is similar to match_limit, but instead
+ The match_limit_recursion field is similar to match_limit, but instead
of limiting the total number of times that match() is called, it limits
- the depth of recursion. The recursion depth is a smaller number than
- the total number of calls, because not all calls to match() are recur-
+ the depth of recursion. The recursion depth is a smaller number than
+ the total number of calls, because not all calls to match() are recur-
sive. This limit is of use only if it is set smaller than match_limit.
- Limiting the recursion depth limits the amount of stack that can be
+ Limiting the recursion depth limits the amount of stack that can be
used, or, when PCRE has been compiled to use memory on the heap instead
of the stack, the amount of heap memory that can be used.
- The default value for match_limit_recursion can be set when PCRE is
- built; the default default is the same value as the default for
- match_limit. You can override the default by suppling pcre_exec() with
- a pcre_extra block in which match_limit_recursion is set, and
- PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the flags field. If the
+ The default value for match_limit_recursion can be set when PCRE is
+ built; the default default is the same value as the default for
+ match_limit. You can override the default by suppling pcre_exec() with
+ a pcre_extra block in which match_limit_recursion is set, and
+ PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the flags field. If the
limit is exceeded, pcre_exec() returns PCRE_ERROR_RECURSIONLIMIT.
- The pcre_callout field is used in conjunction with the "callout" fea-
+ The pcre_callout field is used in conjunction with the "callout" fea-
ture, which is described in the pcrecallout documentation.
- The tables field is used to pass a character tables pointer to
- pcre_exec(); this overrides the value that is stored with the compiled
- pattern. A non-NULL value is stored with the compiled pattern only if
- custom tables were supplied to pcre_compile() via its tableptr argu-
+ The tables field is used to pass a character tables pointer to
+ pcre_exec(); this overrides the value that is stored with the compiled
+ pattern. A non-NULL value is stored with the compiled pattern only if
+ custom tables were supplied to pcre_compile() via its tableptr argu-
ment. If NULL is passed to pcre_exec() using this mechanism, it forces
- PCRE's internal tables to be used. This facility is helpful when re-
- using patterns that have been saved after compiling with an external
- set of tables, because the external tables might be at a different
- address when pcre_exec() is called. See the pcreprecompile documenta-
+ PCRE's internal tables to be used. This facility is helpful when re-
+ using patterns that have been saved after compiling with an external
+ set of tables, because the external tables might be at a different
+ address when pcre_exec() is called. See the pcreprecompile documenta-
tion for a discussion of saving compiled patterns for later use.
Option bits for pcre_exec()
- The unused bits of the options argument for pcre_exec() must be zero.
- The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_xxx,
- PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_START_OPTIMIZE,
+ The unused bits of the options argument for pcre_exec() must be zero.
+ The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_xxx,
+ PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_START_OPTIMIZE,
PCRE_NO_UTF8_CHECK and PCRE_PARTIAL.
PCRE_ANCHORED
- The PCRE_ANCHORED option limits pcre_exec() to matching at the first
- matching position. If a pattern was compiled with PCRE_ANCHORED, or
- turned out to be anchored by virtue of its contents, it cannot be made
+ The PCRE_ANCHORED option limits pcre_exec() to matching at the first
+ matching position. If a pattern was compiled with PCRE_ANCHORED, or
+ turned out to be anchored by virtue of its contents, it cannot be made
unachored at matching time.
PCRE_BSR_ANYCRLF
PCRE_BSR_UNICODE
These options (which are mutually exclusive) control what the \R escape
- sequence matches. The choice is either to match only CR, LF, or CRLF,
- or to match any Unicode newline sequence. These options override the
+ sequence matches. The choice is either to match only CR, LF, or CRLF,
+ or to match any Unicode newline sequence. These options override the
choice that was made or defaulted when the pattern was compiled.
PCRE_NEWLINE_CR
@@ -1950,232 +1952,232 @@
PCRE_NEWLINE_ANYCRLF
PCRE_NEWLINE_ANY
- These options override the newline definition that was chosen or
- defaulted when the pattern was compiled. For details, see the descrip-
- tion of pcre_compile() above. During matching, the newline choice
- affects the behaviour of the dot, circumflex, and dollar metacharac-
- ters. It may also alter the way the match position is advanced after a
+ These options override the newline definition that was chosen or
+ defaulted when the pattern was compiled. For details, see the descrip-
+ tion of pcre_compile() above. During matching, the newline choice
+ affects the behaviour of the dot, circumflex, and dollar metacharac-
+ ters. It may also alter the way the match position is advanced after a
match failure for an unanchored pattern.
- When PCRE_NEWLINE_CRLF, PCRE_NEWLINE_ANYCRLF, or PCRE_NEWLINE_ANY is
- set, and a match attempt for an unanchored pattern fails when the cur-
- rent position is at a CRLF sequence, and the pattern contains no
- explicit matches for CR or LF characters, the match position is
+ When PCRE_NEWLINE_CRLF, PCRE_NEWLINE_ANYCRLF, or PCRE_NEWLINE_ANY is
+ set, and a match attempt for an unanchored pattern fails when the cur-
+ rent position is at a CRLF sequence, and the pattern contains no
+ explicit matches for CR or LF characters, the match position is
advanced by two characters instead of one, in other words, to after the
CRLF.
The above rule is a compromise that makes the most common cases work as
- expected. For example, if the pattern is .+A (and the PCRE_DOTALL
+ expected. For example, if the pattern is .+A (and the PCRE_DOTALL
option is not set), it does not match the string "\r\nA" because, after
- failing at the start, it skips both the CR and the LF before retrying.
- However, the pattern [\r\n]A does match that string, because it con-
+ failing at the start, it skips both the CR and the LF before retrying.
+ However, the pattern [\r\n]A does match that string, because it con-
tains an explicit CR or LF reference, and so advances only by one char-
acter after the first failure.
An explicit match for CR of LF is either a literal appearance of one of
- those characters, or one of the \r or \n escape sequences. Implicit
- matches such as [^X] do not count, nor does \s (which includes CR and
+ those characters, or one of the \r or \n escape sequences. Implicit
+ matches such as [^X] do not count, nor does \s (which includes CR and
LF in the characters that it matches).
- Notwithstanding the above, anomalous effects may still occur when CRLF
+ Notwithstanding the above, anomalous effects may still occur when CRLF
is a valid newline sequence and explicit \r or \n escapes appear in the
pattern.
PCRE_NOTBOL
This option specifies that first character of the subject string is not
- the beginning of a line, so the circumflex metacharacter should not
- match before it. Setting this without PCRE_MULTILINE (at compile time)
- causes circumflex never to match. This option affects only the behav-
+ the beginning of a line, so the circumflex metacharacter should not
+ match before it. Setting this without PCRE_MULTILINE (at compile time)
+ causes circumflex never to match. This option affects only the behav-
iour of the circumflex metacharacter. It does not affect \A.
PCRE_NOTEOL
This option specifies that the end of the subject string is not the end
- of a line, so the dollar metacharacter should not match it nor (except
- in multiline mode) a newline immediately before it. Setting this with-
+ of a line, so the dollar metacharacter should not match it nor (except
+ in multiline mode) a newline immediately before it. Setting this with-
out PCRE_MULTILINE (at compile time) causes dollar never to match. This
- option affects only the behaviour of the dollar metacharacter. It does
+ option affects only the behaviour of the dollar metacharacter. It does
not affect \Z or \z.
PCRE_NOTEMPTY
An empty string is not considered to be a valid match if this option is
- set. If there are alternatives in the pattern, they are tried. If all
- the alternatives match the empty string, the entire match fails. For
+ set. If there are alternatives in the pattern, they are tried. If all
+ the alternatives match the empty string, the entire match fails. For
example, if the pattern
a?b?
- is applied to a string not beginning with "a" or "b", it matches the
- empty string at the start of the subject. With PCRE_NOTEMPTY set, this
+ is applied to a string not beginning with "a" or "b", it matches the
+ empty string at the start of the subject. With PCRE_NOTEMPTY set, this
match is not valid, so PCRE searches further into the string for occur-
rences of "a" or "b".
Perl has no direct equivalent of PCRE_NOTEMPTY, but it does make a spe-
- cial case of a pattern match of the empty string within its split()
- function, and when using the /g modifier. It is possible to emulate
+ cial case of a pattern match of the empty string within its split()
+ function, and when using the /g modifier. It is possible to emulate
Perl's behaviour after matching a null string by first trying the match
again at the same offset with PCRE_NOTEMPTY and PCRE_ANCHORED, and then
- if that fails by advancing the starting offset (see below) and trying
+ if that fails by advancing the starting offset (see below) and trying
an ordinary match again. There is some code that demonstrates how to do
this in the pcredemo.c sample program.
PCRE_NO_START_OPTIMIZE
- There are a number of optimizations that pcre_exec() uses at the start
- of a match, in order to speed up the process. For example, if it is
- known that a match must start with a specific character, it searches
+ There are a number of optimizations that pcre_exec() uses at the start
+ of a match, in order to speed up the process. For example, if it is
+ known that a match must start with a specific character, it searches
the subject for that character, and fails immediately if it cannot find
- it, without actually running the main matching function. When callouts
- are in use, these optimizations can cause them to be skipped. This
- option disables the "start-up" optimizations, causing performance to
+ it, without actually running the main matching function. When callouts
+ are in use, these optimizations can cause them to be skipped. This
+ option disables the "start-up" optimizations, causing performance to
suffer, but ensuring that the callouts do occur.
PCRE_NO_UTF8_CHECK
When PCRE_UTF8 is set at compile time, the validity of the subject as a
- UTF-8 string is automatically checked when pcre_exec() is subsequently
- called. The value of startoffset is also checked to ensure that it
- points to the start of a UTF-8 character. There is a discussion about
- the validity of UTF-8 strings in the section on UTF-8 support in the
- main pcre page. If an invalid UTF-8 sequence of bytes is found,
- pcre_exec() returns the error PCRE_ERROR_BADUTF8. If startoffset con-
+ UTF-8 string is automatically checked when pcre_exec() is subsequently
+ called. The value of startoffset is also checked to ensure that it
+ points to the start of a UTF-8 character. There is a discussion about
+ the validity of UTF-8 strings in the section on UTF-8 support in the
+ main pcre page. If an invalid UTF-8 sequence of bytes is found,
+ pcre_exec() returns the error PCRE_ERROR_BADUTF8. If startoffset con-
tains an invalid value, PCRE_ERROR_BADUTF8_OFFSET is returned.
- If you already know that your subject is valid, and you want to skip
- these checks for performance reasons, you can set the
- PCRE_NO_UTF8_CHECK option when calling pcre_exec(). You might want to
- do this for the second and subsequent calls to pcre_exec() if you are
- making repeated calls to find all the matches in a single subject
- string. However, you should be sure that the value of startoffset
- points to the start of a UTF-8 character. When PCRE_NO_UTF8_CHECK is
- set, the effect of passing an invalid UTF-8 string as a subject, or a
- value of startoffset that does not point to the start of a UTF-8 char-
+ If you already know that your subject is valid, and you want to skip
+ these checks for performance reasons, you can set the
+ PCRE_NO_UTF8_CHECK option when calling pcre_exec(). You might want to
+ do this for the second and subsequent calls to pcre_exec() if you are
+ making repeated calls to find all the matches in a single subject
+ string. However, you should be sure that the value of startoffset
+ points to the start of a UTF-8 character. When PCRE_NO_UTF8_CHECK is
+ set, the effect of passing an invalid UTF-8 string as a subject, or a
+ value of startoffset that does not point to the start of a UTF-8 char-
acter, is undefined. Your program may crash.
PCRE_PARTIAL
- This option turns on the partial matching feature. If the subject
- string fails to match the pattern, but at some point during the match-
- ing process the end of the subject was reached (that is, the subject
- partially matches the pattern and the failure to match occurred only
- because there were not enough subject characters), pcre_exec() returns
- PCRE_ERROR_PARTIAL instead of PCRE_ERROR_NOMATCH. When PCRE_PARTIAL is
- used, there are restrictions on what may appear in the pattern. These
+ This option turns on the partial matching feature. If the subject
+ string fails to match the pattern, but at some point during the match-
+ ing process the end of the subject was reached (that is, the subject
+ partially matches the pattern and the failure to match occurred only
+ because there were not enough subject characters), pcre_exec() returns
+ PCRE_ERROR_PARTIAL instead of PCRE_ERROR_NOMATCH. When PCRE_PARTIAL is
+ used, there are restrictions on what may appear in the pattern. These
are discussed in the pcrepartial documentation.
The string to be matched by pcre_exec()
- The subject string is passed to pcre_exec() as a pointer in subject, a
+ The subject string is passed to pcre_exec() as a pointer in subject, a
length (in bytes) in length, and a starting byte offset in startoffset.
In UTF-8 mode, the byte offset must point to the start of a UTF-8 char-
- acter. Unlike the pattern string, the subject may contain binary zero
- bytes. When the starting offset is zero, the search for a match starts
- at the beginning of the subject, and this is by far the most common
+ acter. Unlike the pattern string, the subject may contain binary zero
+ bytes. When the starting offset is zero, the search for a match starts
+ at the beginning of the subject, and this is by far the most common
case.
- A non-zero starting offset is useful when searching for another match
- in the same subject by calling pcre_exec() again after a previous suc-
- cess. Setting startoffset differs from just passing over a shortened
- string and setting PCRE_NOTBOL in the case of a pattern that begins
+ A non-zero starting offset is useful when searching for another match
+ in the same subject by calling pcre_exec() again after a previous suc-
+ cess. Setting startoffset differs from just passing over a shortened
+ string and setting PCRE_NOTBOL in the case of a pattern that begins
with any kind of lookbehind. For example, consider the pattern
\Biss\B
- which finds occurrences of "iss" in the middle of words. (\B matches
- only if the current position in the subject is not a word boundary.)
- When applied to the string "Mississipi" the first call to pcre_exec()
- finds the first occurrence. If pcre_exec() is called again with just
- the remainder of the subject, namely "issipi", it does not match,
+ which finds occurrences of "iss" in the middle of words. (\B matches
+ only if the current position in the subject is not a word boundary.)
+ When applied to the string "Mississipi" the first call to pcre_exec()
+ finds the first occurrence. If pcre_exec() is called again with just
+ the remainder of the subject, namely "issipi", it does not match,
because \B is always false at the start of the subject, which is deemed
- to be a word boundary. However, if pcre_exec() is passed the entire
+ to be a word boundary. However, if pcre_exec() is passed the entire
string again, but with startoffset set to 4, it finds the second occur-
- rence of "iss" because it is able to look behind the starting point to
+ rence of "iss" because it is able to look behind the starting point to
discover that it is preceded by a letter.
- If a non-zero starting offset is passed when the pattern is anchored,
+ If a non-zero starting offset is passed when the pattern is anchored,
one attempt to match at the given offset is made. This can only succeed
- if the pattern does not require the match to be at the start of the
+ if the pattern does not require the match to be at the start of the
subject.
How pcre_exec() returns captured substrings
- In general, a pattern matches a certain portion of the subject, and in
- addition, further substrings from the subject may be picked out by
- parts of the pattern. Following the usage in Jeffrey Friedl's book,
- this is called "capturing" in what follows, and the phrase "capturing
- subpattern" is used for a fragment of a pattern that picks out a sub-
- string. PCRE supports several other kinds of parenthesized subpattern
+ In general, a pattern matches a certain portion of the subject, and in
+ addition, further substrings from the subject may be picked out by
+ parts of the pattern. Following the usage in Jeffrey Friedl's book,
+ this is called "capturing" in what follows, and the phrase "capturing
+ subpattern" is used for a fragment of a pattern that picks out a sub-
+ string. PCRE supports several other kinds of parenthesized subpattern
that do not cause substrings to be captured.
Captured substrings are returned to the caller via a vector of integers
- whose address is passed in ovector. The number of elements in the vec-
- tor is passed in ovecsize, which must be a non-negative number. Note:
+ whose address is passed in ovector. The number of elements in the vec-
+ tor is passed in ovecsize, which must be a non-negative number. Note:
this argument is NOT the size of ovector in bytes.
- The first two-thirds of the vector is used to pass back captured sub-
- strings, each substring using a pair of integers. The remaining third
- of the vector is used as workspace by pcre_exec() while matching cap-
- turing subpatterns, and is not available for passing back information.
- The number passed in ovecsize should always be a multiple of three. If
+ The first two-thirds of the vector is used to pass back captured sub-
+ strings, each substring using a pair of integers. The remaining third
+ of the vector is used as workspace by pcre_exec() while matching cap-
+ turing subpatterns, and is not available for passing back information.
+ The number passed in ovecsize should always be a multiple of three. If
it is not, it is rounded down.
- When a match is successful, information about captured substrings is
- returned in pairs of integers, starting at the beginning of ovector,
- and continuing up to two-thirds of its length at the most. The first
- element of each pair is set to the byte offset of the first character
- in a substring, and the second is set to the byte offset of the first
- character after the end of a substring. Note: these values are always
+ When a match is successful, information about captured substrings is
+ returned in pairs of integers, starting at the beginning of ovector,
+ and continuing up to two-thirds of its length at the most. The first
+ element of each pair is set to the byte offset of the first character
+ in a substring, and the second is set to the byte offset of the first
+ character after the end of a substring. Note: these values are always
byte offsets, even in UTF-8 mode. They are not character counts.
- The first pair of integers, ovector[0] and ovector[1], identify the
- portion of the subject string matched by the entire pattern. The next
- pair is used for the first capturing subpattern, and so on. The value
+ The first pair of integers, ovector[0] and ovector[1], identify the
+ portion of the subject string matched by the entire pattern. The next
+ pair is used for the first capturing subpattern, and so on. The value
returned by pcre_exec() is one more than the highest numbered pair that
- has been set. For example, if two substrings have been captured, the
- returned value is 3. If there are no capturing subpatterns, the return
+ has been set. For example, if two substrings have been captured, the
+ returned value is 3. If there are no capturing subpatterns, the return
value from a successful match is 1, indicating that just the first pair
of offsets has been set.
If a capturing subpattern is matched repeatedly, it is the last portion
of the string that it matched that is returned.
- If the vector is too small to hold all the captured substring offsets,
+ If the vector is too small to hold all the captured substring offsets,
it is used as far as possible (up to two-thirds of its length), and the
- function returns a value of zero. If the substring offsets are not of
- interest, pcre_exec() may be called with ovector passed as NULL and
- ovecsize as zero. However, if the pattern contains back references and
- the ovector is not big enough to remember the related substrings, PCRE
- has to get additional memory for use during matching. Thus it is usu-
+ function returns a value of zero. If the substring offsets are not of
+ interest, pcre_exec() may be called with ovector passed as NULL and
+ ovecsize as zero. However, if the pattern contains back references and
+ the ovector is not big enough to remember the related substrings, PCRE
+ has to get additional memory for use during matching. Thus it is usu-
ally advisable to supply an ovector.
- The pcre_info() function can be used to find out how many capturing
- subpatterns there are in a compiled pattern. The smallest size for
- ovector that will allow for n captured substrings, in addition to the
+ The pcre_info() function can be used to find out how many capturing
+ subpatterns there are in a compiled pattern. The smallest size for
+ ovector that will allow for n captured substrings, in addition to the
offsets of the substring matched by the whole pattern, is (n+1)*3.
- It is possible for capturing subpattern number n+1 to match some part
+ It is possible for capturing subpattern number n+1 to match some part
of the subject when subpattern n has not been used at all. For example,
- if the string "abc" is matched against the pattern (a|(z))(bc) the
+ if the string "abc" is matched against the pattern (a|(z))(bc) the
return from the function is 4, and subpatterns 1 and 3 are matched, but
- 2 is not. When this happens, both values in the offset pairs corre-
+ 2 is not. When this happens, both values in the offset pairs corre-
sponding to unused subpatterns are set to -1.
- Offset values that correspond to unused subpatterns at the end of the
- expression are also set to -1. For example, if the string "abc" is
- matched against the pattern (abc)(x(yz)?)? subpatterns 2 and 3 are not
- matched. The return from the function is 2, because the highest used
+ Offset values that correspond to unused subpatterns at the end of the
+ expression are also set to -1. For example, if the string "abc" is
+ matched against the pattern (abc)(x(yz)?)? subpatterns 2 and 3 are not
+ matched. The return from the function is 2, because the highest used
capturing subpattern number is 1. However, you can refer to the offsets
- for the second and third capturing subpatterns if you wish (assuming
+ for the second and third capturing subpatterns if you wish (assuming
the vector is large enough, of course).
- Some convenience functions are provided for extracting the captured
+ Some convenience functions are provided for extracting the captured
substrings as separate strings. These are described below.
Error return values from pcre_exec()
- If pcre_exec() fails, it returns a negative number. The following are
+ If pcre_exec() fails, it returns a negative number. The following are
defined in the header file:
PCRE_ERROR_NOMATCH (-1)
@@ -2184,7 +2186,7 @@
PCRE_ERROR_NULL (-2)
- Either code or subject was passed as NULL, or ovector was NULL and
+ Either code or subject was passed as NULL, or ovector was NULL and
ovecsize was not zero.
PCRE_ERROR_BADOPTION (-3)
@@ -2193,69 +2195,69 @@
PCRE_ERROR_BADMAGIC (-4)
- PCRE stores a 4-byte "magic number" at the start of the compiled code,
+ PCRE stores a 4-byte "magic number" at the start of the compiled code,
to catch the case when it is passed a junk pointer and to detect when a
pattern that was compiled in an environment of one endianness is run in
- an environment with the other endianness. This is the error that PCRE
+ an environment with the other endianness. This is the error that PCRE
gives when the magic number is not present.
PCRE_ERROR_UNKNOWN_OPCODE (-5)
While running the pattern match, an unknown item was encountered in the
- compiled pattern. This error could be caused by a bug in PCRE or by
+ compiled pattern. This error could be caused by a bug in PCRE or by
overwriting of the compiled pattern.
PCRE_ERROR_NOMEMORY (-6)
- If a pattern contains back references, but the ovector that is passed
+ If a pattern contains back references, but the ovector that is passed
to pcre_exec() is not big enough to remember the referenced substrings,
- PCRE gets a block of memory at the start of matching to use for this
- purpose. If the call via pcre_malloc() fails, this error is given. The
+ PCRE gets a block of memory at the start of matching to use for this
+ purpose. If the call via pcre_malloc() fails, this error is given. The
memory is automatically freed at the end of matching.
PCRE_ERROR_NOSUBSTRING (-7)
- This error is used by the pcre_copy_substring(), pcre_get_substring(),
+ This error is used by the pcre_copy_substring(), pcre_get_substring(),
and pcre_get_substring_list() functions (see below). It is never
returned by pcre_exec().
PCRE_ERROR_MATCHLIMIT (-8)
- The backtracking limit, as specified by the match_limit field in a
- pcre_extra structure (or defaulted) was reached. See the description
+ The backtracking limit, as specified by the match_limit field in a
+ pcre_extra structure (or defaulted) was reached. See the description
above.
PCRE_ERROR_CALLOUT (-9)
This error is never generated by pcre_exec() itself. It is provided for
- use by callout functions that want to yield a distinctive error code.
+ use by callout functions that want to yield a distinctive error code.
See the pcrecallout documentation for details.
PCRE_ERROR_BADUTF8 (-10)
- A string that contains an invalid UTF-8 byte sequence was passed as a
+ A string that contains an invalid UTF-8 byte sequence was passed as a
subject.
PCRE_ERROR_BADUTF8_OFFSET (-11)
The UTF-8 byte sequence that was passed as a subject was valid, but the
- value of startoffset did not point to the beginning of a UTF-8 charac-
+ value of startoffset did not point to the beginning of a UTF-8 charac-
ter.
PCRE_ERROR_PARTIAL (-12)
- The subject string did not match, but it did match partially. See the
+ The subject string did not match, but it did match partially. See the
pcrepartial documentation for details of partial matching.
PCRE_ERROR_BADPARTIAL (-13)
- The PCRE_PARTIAL option was used with a compiled pattern containing
- items that are not supported for partial matching. See the pcrepartial
+ The PCRE_PARTIAL option was used with a compiled pattern containing
+ items that are not supported for partial matching. See the pcrepartial
documentation for details of partial matching.
PCRE_ERROR_INTERNAL (-14)
- An unexpected internal error has occurred. This error could be caused
+ An unexpected internal error has occurred. This error could be caused
by a bug in PCRE or by overwriting of the compiled pattern.
PCRE_ERROR_BADCOUNT (-15)
@@ -2265,7 +2267,7 @@
PCRE_ERROR_RECURSIONLIMIT (-21)
The internal recursion limit, as specified by the match_limit_recursion
- field in a pcre_extra structure (or defaulted) was reached. See the
+ field in a pcre_extra structure (or defaulted) was reached. See the
description above.
PCRE_ERROR_BADNEWLINE (-23)
@@ -2288,78 +2290,78 @@
int pcre_get_substring_list(const char *subject,
int *ovector, int stringcount, const char ***listptr);
- Captured substrings can be accessed directly by using the offsets
- returned by pcre_exec() in ovector. For convenience, the functions
+ Captured substrings can be accessed directly by using the offsets
+ returned by pcre_exec() in ovector. For convenience, the functions
pcre_copy_substring(), pcre_get_substring(), and pcre_get_sub-
- string_list() are provided for extracting captured substrings as new,
- separate, zero-terminated strings. These functions identify substrings
- by number. The next section describes functions for extracting named
+ string_list() are provided for extracting captured substrings as new,
+ separate, zero-terminated strings. These functions identify substrings
+ by number. The next section describes functions for extracting named
substrings.
- A substring that contains a binary zero is correctly extracted and has
- a further zero added on the end, but the result is not, of course, a C
- string. However, you can process such a string by referring to the
- length that is returned by pcre_copy_substring() and pcre_get_sub-
+ A substring that contains a binary zero is correctly extracted and has
+ a further zero added on the end, but the result is not, of course, a C
+ string. However, you can process such a string by referring to the
+ length that is returned by pcre_copy_substring() and pcre_get_sub-
string(). Unfortunately, the interface to pcre_get_substring_list() is
- not adequate for handling strings containing binary zeros, because the
+ not adequate for handling strings containing binary zeros, because the
end of the final string is not independently indicated.
- The first three arguments are the same for all three of these func-
- tions: subject is the subject string that has just been successfully
+ The first three arguments are the same for all three of these func-
+ tions: subject is the subject string that has just been successfully
matched, ovector is a pointer to the vector of integer offsets that was
passed to pcre_exec(), and stringcount is the number of substrings that
- were captured by the match, including the substring that matched the
+ were captured by the match, including the substring that matched the
entire regular expression. This is the value returned by pcre_exec() if
- it is greater than zero. If pcre_exec() returned zero, indicating that
- it ran out of space in ovector, the value passed as stringcount should
+ it is greater than zero. If pcre_exec() returned zero, indicating that
+ it ran out of space in ovector, the value passed as stringcount should
be the number of elements in the vector divided by three.
- The functions pcre_copy_substring() and pcre_get_substring() extract a
- single substring, whose number is given as stringnumber. A value of
- zero extracts the substring that matched the entire pattern, whereas
- higher values extract the captured substrings. For pcre_copy_sub-
- string(), the string is placed in buffer, whose length is given by
- buffersize, while for pcre_get_substring() a new block of memory is
- obtained via pcre_malloc, and its address is returned via stringptr.
- The yield of the function is the length of the string, not including
+ The functions pcre_copy_substring() and pcre_get_substring() extract a
+ single substring, whose number is given as stringnumber. A value of
+ zero extracts the substring that matched the entire pattern, whereas
+ higher values extract the captured substrings. For pcre_copy_sub-
+ string(), the string is placed in buffer, whose length is given by
+ buffersize, while for pcre_get_substring() a new block of memory is
+ obtained via pcre_malloc, and its address is returned via stringptr.
+ The yield of the function is the length of the string, not including
the terminating zero, or one of these error codes:
PCRE_ERROR_NOMEMORY (-6)
- The buffer was too small for pcre_copy_substring(), or the attempt to
+ The buffer was too small for pcre_copy_substring(), or the attempt to
get memory failed for pcre_get_substring().
PCRE_ERROR_NOSUBSTRING (-7)
There is no substring whose number is stringnumber.
- The pcre_get_substring_list() function extracts all available sub-
- strings and builds a list of pointers to them. All this is done in a
+ The pcre_get_substring_list() function extracts all available sub-
+ strings and builds a list of pointers to them. All this is done in a
single block of memory that is obtained via pcre_malloc. The address of
- the memory block is returned via listptr, which is also the start of
- the list of string pointers. The end of the list is marked by a NULL
- pointer. The yield of the function is zero if all went well, or the
+ the memory block is returned via listptr, which is also the start of
+ the list of string pointers. The end of the list is marked by a NULL
+ pointer. The yield of the function is zero if all went well, or the
error code
PCRE_ERROR_NOMEMORY (-6)
if the attempt to get the memory block failed.
- When any of these functions encounter a substring that is unset, which
- can happen when capturing subpattern number n+1 matches some part of
- the subject, but subpattern n has not been used at all, they return an
+ When any of these functions encounter a substring that is unset, which
+ can happen when capturing subpattern number n+1 matches some part of
+ the subject, but subpattern n has not been used at all, they return an
empty string. This can be distinguished from a genuine zero-length sub-
- string by inspecting the appropriate offset in ovector, which is nega-
+ string by inspecting the appropriate offset in ovector, which is nega-
tive for unset substrings.
- The two convenience functions pcre_free_substring() and pcre_free_sub-
- string_list() can be used to free the memory returned by a previous
+ The two convenience functions pcre_free_substring() and pcre_free_sub-
+ string_list() can be used to free the memory returned by a previous
call of pcre_get_substring() or pcre_get_substring_list(), respec-
- tively. They do nothing more than call the function pointed to by
- pcre_free, which of course could be called directly from a C program.
- However, PCRE is used in some situations where it is linked via a spe-
- cial interface to another programming language that cannot use
- pcre_free directly; it is for these cases that the functions are pro-
+ tively. They do nothing more than call the function pointed to by
+ pcre_free, which of course could be called directly from a C program.
+ However, PCRE is used in some situations where it is linked via a spe-
+ cial interface to another programming language that cannot use
+ pcre_free directly; it is for these cases that the functions are pro-
vided.
@@ -2378,7 +2380,7 @@
int stringcount, const char *stringname,
const char **stringptr);
- To extract a substring by name, you first have to find associated num-
+ To extract a substring by name, you first have to find associated num-
ber. For example, for this pattern
(a+)b(?<xxx>\d+)...
@@ -2387,31 +2389,31 @@
be unique (PCRE_DUPNAMES was not set), you can find the number from the
name by calling pcre_get_stringnumber(). The first argument is the com-
piled pattern, and the second is the name. The yield of the function is
- the subpattern number, or PCRE_ERROR_NOSUBSTRING (-7) if there is no
+ the subpattern number, or PCRE_ERROR_NOSUBSTRING (-7) if there is no
subpattern of that name.
Given the number, you can extract the substring directly, or use one of
the functions described in the previous section. For convenience, there
are also two functions that do the whole job.
- Most of the arguments of pcre_copy_named_substring() and
- pcre_get_named_substring() are the same as those for the similarly
- named functions that extract by number. As these are described in the
- previous section, they are not re-described here. There are just two
+ Most of the arguments of pcre_copy_named_substring() and
+ pcre_get_named_substring() are the same as those for the similarly
+ named functions that extract by number. As these are described in the
+ previous section, they are not re-described here. There are just two
differences:
- First, instead of a substring number, a substring name is given. Sec-
+ First, instead of a substring number, a substring name is given. Sec-
ond, there is an extra argument, given at the start, which is a pointer
- to the compiled pattern. This is needed in order to gain access to the
+ to the compiled pattern. This is needed in order to gain access to the
name-to-number translation table.
- These functions call pcre_get_stringnumber(), and if it succeeds, they
- then call pcre_copy_substring() or pcre_get_substring(), as appropri-
- ate. NOTE: If PCRE_DUPNAMES is set and there are duplicate names, the
+ These functions call pcre_get_stringnumber(), and if it succeeds, they
+ then call pcre_copy_substring() or pcre_get_substring(), as appropri-
+ ate. NOTE: If PCRE_DUPNAMES is set and there are duplicate names, the
behaviour may not be what you want (see the next section).
- Warning: If the pattern uses the "(?|" feature to set up multiple sub-
- patterns with the same number, you cannot use names to distinguish
+ Warning: If the pattern uses the "(?|" feature to set up multiple sub-
+ patterns with the same number, you cannot use names to distinguish
them, because names are not included in the compiled code. The matching
process uses only numbers.
@@ -2421,47 +2423,47 @@
int pcre_get_stringtable_entries(const pcre *code,
const char *name, char **first, char **last);
- When a pattern is compiled with the PCRE_DUPNAMES option, names for
- subpatterns are not required to be unique. Normally, patterns with
- duplicate names are such that in any one match, only one of the named
- subpatterns participates. An example is shown in the pcrepattern docu-
+ When a pattern is compiled with the PCRE_DUPNAMES option, names for
+ subpatterns are not required to be unique. Normally, patterns with
+ duplicate names are such that in any one match, only one of the named
+ subpatterns participates. An example is shown in the pcrepattern docu-
mentation.
- When duplicates are present, pcre_copy_named_substring() and
- pcre_get_named_substring() return the first substring corresponding to
- the given name that is set. If none are set, PCRE_ERROR_NOSUBSTRING
- (-7) is returned; no data is returned. The pcre_get_stringnumber()
- function returns one of the numbers that are associated with the name,
+ When duplicates are present, pcre_copy_named_substring() and
+ pcre_get_named_substring() return the first substring corresponding to
+ the given name that is set. If none are set, PCRE_ERROR_NOSUBSTRING
+ (-7) is returned; no data is returned. The pcre_get_stringnumber()
+ function returns one of the numbers that are associated with the name,
but it is not defined which it is.
- If you want to get full details of all captured substrings for a given
- name, you must use the pcre_get_stringtable_entries() function. The
+ If you want to get full details of all captured substrings for a given
+ name, you must use the pcre_get_stringtable_entries() function. The
first argument is the compiled pattern, and the second is the name. The
- third and fourth are pointers to variables which are updated by the
+ third and fourth are pointers to variables which are updated by the
function. After it has run, they point to the first and last entries in
- the name-to-number table for the given name. The function itself
- returns the length of each entry, or PCRE_ERROR_NOSUBSTRING (-7) if
- there are none. The format of the table is described above in the sec-
- tion entitled Information about a pattern. Given all the relevant
- entries for the name, you can extract each of their numbers, and hence
+ the name-to-number table for the given name. The function itself
+ returns the length of each entry, or PCRE_ERROR_NOSUBSTRING (-7) if
+ there are none. The format of the table is described above in the sec-
+ tion entitled Information about a pattern. Given all the relevant
+ entries for the name, you can extract each of their numbers, and hence
the captured data, if any.
FINDING ALL POSSIBLE MATCHES
- The traditional matching function uses a similar algorithm to Perl,
+ The traditional matching function uses a similar algorithm to Perl,
which stops when it finds the first match, starting at a given point in
- the subject. If you want to find all possible matches, or the longest
- possible match, consider using the alternative matching function (see
- below) instead. If you cannot use the alternative function, but still
- need to find all possible matches, you can kludge it up by making use
+ the subject. If you want to find all possible matches, or the longest
+ possible match, consider using the alternative matching function (see
+ below) instead. If you cannot use the alternative function, but still
+ need to find all possible matches, you can kludge it up by making use
of the callout facility, which is described in the pcrecallout documen-
tation.
What you have to do is to insert a callout right at the end of the pat-
- tern. When your callout function is called, extract and save the cur-
- rent matched substring. Then return 1, which forces pcre_exec() to
- backtrack and try other alternatives. Ultimately, when it runs out of
+ tern. When your callout function is called, extract and save the cur-
+ rent matched substring. Then return 1, which forces pcre_exec() to
+ backtrack and try other alternatives. Ultimately, when it runs out of
matches, pcre_exec() will yield PCRE_ERROR_NOMATCH.
@@ -2472,25 +2474,25 @@
int options, int *ovector, int ovecsize,
int *workspace, int wscount);
- The function pcre_dfa_exec() is called to match a subject string
- against a compiled pattern, using a matching algorithm that scans the
- subject string just once, and does not backtrack. This has different
- characteristics to the normal algorithm, and is not compatible with
- Perl. Some of the features of PCRE patterns are not supported. Never-
- theless, there are times when this kind of matching can be useful. For
+ The function pcre_dfa_exec() is called to match a subject string
+ against a compiled pattern, using a matching algorithm that scans the
+ subject string just once, and does not backtrack. This has different
+ characteristics to the normal algorithm, and is not compatible with
+ Perl. Some of the features of PCRE patterns are not supported. Never-
+ theless, there are times when this kind of matching can be useful. For
a discussion of the two matching algorithms, see the pcrematching docu-
mentation.
- The arguments for the pcre_dfa_exec() function are the same as for
+ The arguments for the pcre_dfa_exec() function are the same as for
pcre_exec(), plus two extras. The ovector argument is used in a differ-
- ent way, and this is described below. The other common arguments are
- used in the same way as for pcre_exec(), so their description is not
+ ent way, and this is described below. The other common arguments are
+ used in the same way as for pcre_exec(), so their description is not
repeated here.
- The two additional arguments provide workspace for the function. The
- workspace vector should contain at least 20 elements. It is used for
+ The two additional arguments provide workspace for the function. The
+ workspace vector should contain at least 20 elements. It is used for
keeping track of multiple paths through the pattern tree. More
- workspace will be needed for patterns and subjects where there are a
+ workspace will be needed for patterns and subjects where there are a
lot of potential matches.
Here is an example of a simple call to pcre_dfa_exec():
@@ -2512,47 +2514,47 @@
Option bits for pcre_dfa_exec()
- The unused bits of the options argument for pcre_dfa_exec() must be
- zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEW-
- LINE_xxx, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK,
+ The unused bits of the options argument for pcre_dfa_exec() must be
+ zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEW-
+ LINE_xxx, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NO_UTF8_CHECK,
PCRE_PARTIAL, PCRE_DFA_SHORTEST, and PCRE_DFA_RESTART. All but the last
three of these are the same as for pcre_exec(), so their description is
not repeated here.
PCRE_PARTIAL
- This has the same general effect as it does for pcre_exec(), but the
- details are slightly different. When PCRE_PARTIAL is set for
- pcre_dfa_exec(), the return code PCRE_ERROR_NOMATCH is converted into
- PCRE_ERROR_PARTIAL if the end of the subject is reached, there have
+ This has the same general effect as it does for pcre_exec(), but the
+ details are slightly different. When PCRE_PARTIAL is set for
+ pcre_dfa_exec(), the return code PCRE_ERROR_NOMATCH is converted into
+ PCRE_ERROR_PARTIAL if the end of the subject is reached, there have
been no complete matches, but there is still at least one matching pos-
- sibility. The portion of the string that provided the partial match is
+ sibility. The portion of the string that provided the partial match is
set as the first matching string.
PCRE_DFA_SHORTEST
- Setting the PCRE_DFA_SHORTEST option causes the matching algorithm to
+ Setting the PCRE_DFA_SHORTEST option causes the matching algorithm to
stop as soon as it has found one match. Because of the way the alterna-
- tive algorithm works, this is necessarily the shortest possible match
+ tive algorithm works, this is necessarily the shortest possible match
at the first possible matching point in the subject string.
PCRE_DFA_RESTART
- When pcre_dfa_exec() is called with the PCRE_PARTIAL option, and
- returns a partial match, it is possible to call it again, with addi-
- tional subject characters, and have it continue with the same match.
- The PCRE_DFA_RESTART option requests this action; when it is set, the
- workspace and wscount options must reference the same vector as before
- because data about the match so far is left in them after a partial
- match. There is more discussion of this facility in the pcrepartial
+ When pcre_dfa_exec() is called with the PCRE_PARTIAL option, and
+ returns a partial match, it is possible to call it again, with addi-
+ tional subject characters, and have it continue with the same match.
+ The PCRE_DFA_RESTART option requests this action; when it is set, the
+ workspace and wscount options must reference the same vector as before
+ because data about the match so far is left in them after a partial
+ match. There is more discussion of this facility in the pcrepartial
documentation.
Successful returns from pcre_dfa_exec()
- When pcre_dfa_exec() succeeds, it may have matched more than one sub-
+ When pcre_dfa_exec() succeeds, it may have matched more than one sub-
string in the subject. Note, however, that all the matches from one run
- of the function start at the same point in the subject. The shorter
- matches are all initial substrings of the longer matches. For example,
+ of the function start at the same point in the subject. The shorter
+ matches are all initial substrings of the longer matches. For example,
if the pattern
<.*>
@@ -2567,61 +2569,61 @@
<something> <something else>
<something> <something else> <something further>
- On success, the yield of the function is a number greater than zero,
- which is the number of matched substrings. The substrings themselves
- are returned in ovector. Each string uses two elements; the first is
- the offset to the start, and the second is the offset to the end. In
- fact, all the strings have the same start offset. (Space could have
- been saved by giving this only once, but it was decided to retain some
- compatibility with the way pcre_exec() returns data, even though the
+ On success, the yield of the function is a number greater than zero,
+ which is the number of matched substrings. The substrings themselves
+ are returned in ovector. Each string uses two elements; the first is
+ the offset to the start, and the second is the offset to the end. In
+ fact, all the strings have the same start offset. (Space could have
+ been saved by giving this only once, but it was decided to retain some
+ compatibility with the way pcre_exec() returns data, even though the
meaning of the strings is different.)
The strings are returned in reverse order of length; that is, the long-
- est matching string is given first. If there were too many matches to
- fit into ovector, the yield of the function is zero, and the vector is
+ est matching string is given first. If there were too many matches to
+ fit into ovector, the yield of the function is zero, and the vector is
filled with the longest matches.
Error returns from pcre_dfa_exec()
- The pcre_dfa_exec() function returns a negative number when it fails.
- Many of the errors are the same as for pcre_exec(), and these are
- described above. There are in addition the following errors that are
+ The pcre_dfa_exec() function returns a negative number when it fails.
+ Many of the errors are the same as for pcre_exec(), and these are
+ described above. There are in addition the following errors that are
specific to pcre_dfa_exec():
PCRE_ERROR_DFA_UITEM (-16)
- This return is given if pcre_dfa_exec() encounters an item in the pat-
- tern that it does not support, for instance, the use of \C or a back
+ This return is given if pcre_dfa_exec() encounters an item in the pat-
+ tern that it does not support, for instance, the use of \C or a back
reference.
PCRE_ERROR_DFA_UCOND (-17)
- This return is given if pcre_dfa_exec() encounters a condition item
- that uses a back reference for the condition, or a test for recursion
+ This return is given if pcre_dfa_exec() encounters a condition item
+ that uses a back reference for the condition, or a test for recursion
in a specific group. These are not supported.
PCRE_ERROR_DFA_UMLIMIT (-18)
- This return is given if pcre_dfa_exec() is called with an extra block
+ This return is given if pcre_dfa_exec() is called with an extra block
that contains a setting of the match_limit field. This is not supported
(it is meaningless).
PCRE_ERROR_DFA_WSSIZE (-19)
- This return is given if pcre_dfa_exec() runs out of space in the
+ This return is given if pcre_dfa_exec() runs out of space in the
workspace vector.
PCRE_ERROR_DFA_RECURSE (-20)
- When a recursive subpattern is processed, the matching function calls
- itself recursively, using private vectors for ovector and workspace.
- This error is given if the output vector is not large enough. This
+ When a recursive subpattern is processed, the matching function calls
+ itself recursively, using private vectors for ovector and workspace.
+ This error is given if the output vector is not large enough. This
should be extremely rare, as a vector of size 1000 is used.
SEE ALSO
- pcrebuild(3), pcrecallout(3), pcrecpp(3)(3), pcrematching(3), pcrepar-
+ pcrebuild(3), pcrecallout(3), pcrecpp(3)(3), pcrematching(3), pcrepar-
tial(3), pcreposix(3), pcreprecompile(3), pcresample(3), pcrestack(3).
@@ -2634,7 +2636,7 @@
REVISION
- Last updated: 17 March 2009
+ Last updated: 11 April 2009
Copyright (c) 1997-2009 University of Cambridge.
------------------------------------------------------------------------------
@@ -2983,11 +2985,17 @@
The original operation of PCRE was on strings of one-byte characters.
However, there is now also support for UTF-8 character strings. To use
this, you must build PCRE to include UTF-8 support, and then call
- pcre_compile() with the PCRE_UTF8 option. How this affects pattern
- matching is mentioned in several places below. There is also a summary
- of UTF-8 features in the section on UTF-8 support in the main pcre
- page.
+ pcre_compile() with the PCRE_UTF8 option. There is also a special
+ sequence that can be given at the start of a pattern:
+ (*UTF8)
+
+ Starting a pattern with this sequence is equivalent to setting the
+ PCRE_UTF8 option. This feature is not Perl-compatible. How setting
+ UTF-8 mode affects pattern matching is mentioned in several places
+ below. There is also a summary of UTF-8 features in the section on
+ UTF-8 support in the main pcre page.
+
The remainder of this document discusses the patterns that are sup-
ported by PCRE when its main matching function, pcre_exec(), is used.
From release 6.0, PCRE offers a second matching function,
@@ -3832,11 +3840,11 @@
can be changed in the same way as the Perl-compatible options by using
the characters J, U and X respectively.
- When an option change occurs at top level (that is, not inside subpat-
- tern parentheses), the change applies to the remainder of the pattern
- that follows. If the change is placed right at the start of a pattern,
- PCRE extracts it into the global options (and it will therefore show up
- in data extracted by the pcre_fullinfo() function).
+ When one of these option changes occurs at top level (that is, not
+ inside subpattern parentheses), the change applies to the remainder of
+ the pattern that follows. If the change is placed right at the start of
+ a pattern, PCRE extracts it into the global options (and it will there-
+ fore show up in data extracted by the pcre_fullinfo() function).
An option change within a subpattern (see below for a description of
subpatterns) affects only that part of the current pattern that follows
@@ -3859,9 +3867,11 @@
Note: There are other PCRE-specific options that can be set by the
application when the compile or match functions are called. In some
- cases the pattern can contain special leading sequences to override
- what the application has set or what has been defaulted. Details are
- given in the section entitled "Newline sequences" above.
+ cases the pattern can contain special leading sequences such as (*CRLF)
+ to override what the application has set or what has been defaulted.
+ Details are given in the section entitled "Newline sequences" above.
+ There is also the (*UTF8) leading sequence that can be used to set
+ UTF-8 mode; this is equivalent to setting the PCRE_UTF8 option.
SUBPATTERNS
@@ -5021,7 +5031,7 @@
REVISION
- Last updated: 18 March 2009
+ Last updated: 11 April 2009
Copyright (c) 1997-2009 University of Cambridge.
------------------------------------------------------------------------------
@@ -5134,14 +5144,16 @@
SCRIPT NAMES FOR \p AND \P
Arabic, Armenian, Balinese, Bengali, Bopomofo, Braille, Buginese,
- Buhid, Canadian_Aboriginal, Cherokee, Common, Coptic, Cuneiform,
- Cypriot, Cyrillic, Deseret, Devanagari, Ethiopic, Georgian, Glagolitic,
- Gothic, Greek, Gujarati, Gurmukhi, Han, Hangul, Hanunoo, Hebrew, Hira-
- gana, Inherited, Kannada, Katakana, Kharoshthi, Khmer, Lao, Latin,
- Limbu, Linear_B, Malayalam, Mongolian, Myanmar, New_Tai_Lue, Nko,
- Ogham, Old_Italic, Old_Persian, Oriya, Osmanya, Phags_Pa, Phoenician,
- Runic, Shavian, Sinhala, Syloti_Nagri, Syriac, Tagalog, Tagbanwa,
- Tai_Le, Tamil, Telugu, Thaana, Thai, Tibetan, Tifinagh, Ugaritic, Yi.
+ Buhid, Canadian_Aboriginal, Carian, Cham, Cherokee, Common, Coptic, Cu-
+ neiform, Cypriot, Cyrillic, Deseret, Devanagari, Ethiopic, Georgian,
+ Glagolitic, Gothic, Greek, Gujarati, Gurmukhi, Han, Hangul, Hanunoo,
+ Hebrew, Hiragana, Inherited, Kannada, Katakana, Kayah_Li, Kharoshthi,
+ Khmer, Lao, Latin, Lepcha, Limbu, Linear_B, Lycian, Lydian, Malayalam,
+ Mongolian, Myanmar, New_Tai_Lue, Nko, Ogham, Old_Italic, Old_Persian,
+ Ol_Chiki, Oriya, Osmanya, Phags_Pa, Phoenician, Rejang, Runic, Saurash-
+ tra, Shavian, Sinhala, Sudanese, Syloti_Nagri, Syriac, Tagalog, Tag-
+ banwa, Tai_Le, Tamil, Telugu, Thaana, Thai, Tibetan, Tifinagh,
+ Ugaritic, Vai, Yi.
CHARACTER CLASSES
@@ -5193,7 +5205,7 @@
ANCHORS AND SIMPLE ASSERTIONS
- \b word boundary
+ \b word boundary (only ASCII letters recognized)
\B not a word boundary
^ start of subject
also after internal newline in multiline mode
@@ -5219,75 +5231,80 @@
CAPTURING
- (...) capturing group
- (?<name>...) named capturing group (Perl)
- (?'name'...) named capturing group (Perl)
- (?P<name>...) named capturing group (Python)
- (?:...) non-capturing group
- (?|...) non-capturing group; reset group numbers for
- capturing groups in each alternative
+ (...) capturing group
+ (?<name>...) named capturing group (Perl)
+ (?'name'...) named capturing group (Perl)
+ (?P<name>...) named capturing group (Python)
+ (?:...) non-capturing group
+ (?|...) non-capturing group; reset group numbers for
+ capturing groups in each alternative
ATOMIC GROUPS
- (?>...) atomic, non-capturing group
+ (?>...) atomic, non-capturing group
COMMENT
- (?#....) comment (not nestable)
+ (?#....) comment (not nestable)
OPTION SETTING
- (?i) caseless
- (?J) allow duplicate names
- (?m) multiline
- (?s) single line (dotall)
- (?U) default ungreedy (lazy)
- (?x) extended (ignore white space)
- (?-...) unset option(s)
+ (?i) caseless
+ (?J) allow duplicate names
+ (?m) multiline
+ (?s) single line (dotall)
+ (?U) default ungreedy (lazy)
+ (?x) extended (ignore white space)
+ (?-...) unset option(s)
+ The following is recognized only at the start of a pattern or after one
+ of the newline-setting options with similar syntax:
+ (*UTF8) set UTF-8 mode
+
+
LOOKAHEAD AND LOOKBEHIND ASSERTIONS
- (?=...) positive look ahead
- (?!...) negative look ahead
- (?<=...) positive look behind
- (?<!...) negative look behind
+ (?=...) positive look ahead
+ (?!...) negative look ahead
+ (?<=...) positive look behind
+ (?<!...) negative look behind
Each top-level branch of a look behind must be of a fixed length.
BACKREFERENCES
- \n reference by number (can be ambiguous)
- \gn reference by number
- \g{n} reference by number
- \g{-n} relative reference by number
- \k<name> reference by name (Perl)
- \k'name' reference by name (Perl)
- \g{name} reference by name (Perl)
- \k{name} reference by name (.NET)
- (?P=name) reference by name (Python)
+ \n reference by number (can be ambiguous)
+ \gn reference by number
+ \g{n} reference by number
+ \g{-n} relative reference by number
+ \k<name> reference by name (Perl)
+ \k'name' reference by name (Perl)
+ \g{name} reference by name (Perl)
+ \k{name} reference by name (.NET)
+ (?P=name) reference by name (Python)
SUBROUTINE REFERENCES (POSSIBLY RECURSIVE)
- (?R) recurse whole pattern
- (?n) call subpattern by absolute number
- (?+n) call subpattern by relative number
- (?-n) call subpattern by relative number
- (?&name) call subpattern by name (Perl)
- (?P>name) call subpattern by name (Python)
- \g<name> call subpattern by name (Oniguruma)
- \g'name' call subpattern by name (Oniguruma)
- \g<n> call subpattern by absolute number (Oniguruma)
- \g'n' call subpattern by absolute number (Oniguruma)
- \g<+n> call subpattern by relative number (PCRE extension)
- \g'+n' call subpattern by relative number (PCRE extension)
- \g<-n> call subpattern by relative number (PCRE extension)
- \g'-n' call subpattern by relative number (PCRE extension)
+ (?R) recurse whole pattern
+ (?n) call subpattern by absolute number
+ (?+n) call subpattern by relative number
+ (?-n) call subpattern by relative number
+ (?&name) call subpattern by name (Perl)
+ (?P>name) call subpattern by name (Python)
+ \g<name> call subpattern by name (Oniguruma)
+ \g'name' call subpattern by name (Oniguruma)
+ \g<n> call subpattern by absolute number (Oniguruma)
+ \g'n' call subpattern by absolute number (Oniguruma)
+ \g<+n> call subpattern by relative number (PCRE extension)
+ \g'+n' call subpattern by relative number (PCRE extension)
+ \g<-n> call subpattern by relative number (PCRE extension)
+ \g'-n' call subpattern by relative number (PCRE extension)
CONDITIONAL PATTERNS
@@ -5295,56 +5312,56 @@
(?(condition)yes-pattern)
(?(condition)yes-pattern|no-pattern)
- (?(n)... absolute reference condition
- (?(+n)... relative reference condition
- (?(-n)... relative reference condition
- (?(<name>)... named reference condition (Perl)
- (?('name')... named reference condition (Perl)
- (?(name)... named reference condition (PCRE)
- (?(R)... overall recursion condition
- (?(Rn)... specific group recursion condition
- (?(R&name)... specific recursion condition
- (?(DEFINE)... define subpattern for reference
- (?(assert)... assertion condition
+ (?(n)... absolute reference condition
+ (?(+n)... relative reference condition
+ (?(-n)... relative reference condition
+ (?(<name>)... named reference condition (Perl)
+ (?('name')... named reference condition (Perl)
+ (?(name)... named reference condition (PCRE)
+ (?(R)... overall recursion condition
+ (?(Rn)... specific group recursion condition
+ (?(R&name)... specific recursion condition
+ (?(DEFINE)... define subpattern for reference
+ (?(assert)... assertion condition
BACKTRACKING CONTROL
The following act immediately they are reached:
- (*ACCEPT) force successful match
- (*FAIL) force backtrack; synonym (*F)
+ (*ACCEPT) force successful match
+ (*FAIL) force backtrack; synonym (*F)
- The following act only when a subsequent match failure causes a back-
+ The following act only when a subsequent match failure causes a back-
track to reach them. They all force a match failure, but they differ in
what happens afterwards. Those that advance the start-of-match point do
so only if the pattern is not anchored.
- (*COMMIT) overall failure, no advance of starting point
- (*PRUNE) advance to next starting character
- (*SKIP) advance start to current matching position
- (*THEN) local failure, backtrack to next alternation
+ (*COMMIT) overall failure, no advance of starting point
+ (*PRUNE) advance to next starting character
+ (*SKIP) advance start to current matching position
+ (*THEN) local failure, backtrack to next alternation
NEWLINE CONVENTIONS
- These are recognized only at the very start of the pattern or after a
- (*BSR_...) option.
+ These are recognized only at the very start of the pattern or after a
+ (*BSR_...) or (*UTF8) option.
- (*CR)
- (*LF)
- (*CRLF)
- (*ANYCRLF)
- (*ANY)
+ (*CR) carriage return only
+ (*LF) linefeed only
+ (*CRLF) carriage return followed by linefeed
+ (*ANYCRLF) all three of the above
+ (*ANY) any Unicode newline sequence
WHAT \R MATCHES
- These are recognized only at the very start of the pattern or after a
- (*...) option that sets the newline convention.
+ These are recognized only at the very start of the pattern or after a
+ (*...) option that sets the newline convention or UTF-8 mode.
- (*BSR_ANYCRLF)
- (*BSR_UNICODE)
+ (*BSR_ANYCRLF) CR, LF, or CRLF
+ (*BSR_UNICODE) any Unicode newline sequence
CALLOUTS
@@ -5367,8 +5384,8 @@
REVISION
- Last updated: 09 April 2008
- Copyright (c) 1997-2008 University of Cambridge.
+ Last updated: 11 April 2009
+ Copyright (c) 1997-2009 University of Cambridge.
------------------------------------------------------------------------------
Modified: code/trunk/doc/pcrepattern.3
===================================================================
--- code/trunk/doc/pcrepattern.3 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/pcrepattern.3 2009-04-11 14:34:02 UTC (rev 416)
@@ -23,11 +23,11 @@
The original operation of PCRE was on strings of one-byte characters. However,
there is now also support for UTF-8 character strings. To use this, you must
build PCRE to include UTF-8 support, and then call \fBpcre_compile()\fP with
-the PCRE_UTF8 option. There is also a special sequence that can be given at the
+the PCRE_UTF8 option. There is also a special sequence that can be given at the
start of a pattern:
.sp
(*UTF8)
-.sp
+.sp
Starting a pattern with this sequence is equivalent to setting the PCRE_UTF8
option. This feature is not Perl-compatible. How setting UTF-8 mode affects
pattern matching is mentioned in several places below. There is also a summary
@@ -1071,7 +1071,7 @@
.\" </a>
"Newline sequences"
.\"
-above. There is also the (*UTF8) leading sequence that can be used to set UTF-8
+above. There is also the (*UTF8) leading sequence that can be used to set UTF-8
mode; this is equivalent to setting the PCRE_UTF8 option.
.
.
Modified: code/trunk/doc/pcresyntax.3
===================================================================
--- code/trunk/doc/pcresyntax.3 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/doc/pcresyntax.3 2009-04-11 14:34:02 UTC (rev 416)
@@ -305,10 +305,10 @@
(?x) extended (ignore white space)
(?-...) unset option(s)
.sp
-The following is recognized only at the start of a pattern or after one of the
+The following is recognized only at the start of a pattern or after one of the
newline-setting options with similar syntax:
.sp
- (*UTF8) set UTF-8 mode
+ (*UTF8) set UTF-8 mode
.
.
.SH "LOOKAHEAD AND LOOKBEHIND ASSERTIONS"
Modified: code/trunk/pcretest.c
===================================================================
--- code/trunk/pcretest.c 2009-04-11 14:22:17 UTC (rev 415)
+++ code/trunk/pcretest.c 2009-04-11 14:34:02 UTC (rev 416)
@@ -1326,7 +1326,7 @@
{
unsigned long int get_options;
-
+
if (timeit > 0)
{
register int i;
@@ -1369,11 +1369,11 @@
}
goto CONTINUE;
}
-
- /* Compilation succeeded. It is now possible to set the UTF-8 option from
- within the regex; check for this so that we know how to process the data
+
+ /* Compilation succeeded. It is now possible to set the UTF-8 option from
+ within the regex; check for this so that we know how to process the data
lines. */
-
+
new_info(re, NULL, PCRE_INFO_OPTIONS, &get_options);
if ((get_options & PCRE_UTF8) != 0) use_utf8 = 1;
@@ -1463,7 +1463,7 @@
fprintf(outfile, "------------------------------------------------------------------\n");
pcre_printint(re, outfile, debug_lengths);
}
-
+
/* We already have the options in get_options (see above) */
if (do_showinfo)
