Revision: 369
http://www.exim.org/viewvc/pcre2?view=rev&revision=369
Author: ph10
Date: 2015-09-12 19:12:01 +0100 (Sat, 12 Sep 2015)
Log Message:
-----------
Update HTML documentation.
Modified Paths:
--------------
code/trunk/doc/html/pcre2_serialize_decode.html
code/trunk/doc/html/pcre2_serialize_encode.html
code/trunk/doc/html/pcre2api.html
code/trunk/doc/html/pcre2pattern.html
code/trunk/doc/html/pcre2posix.html
code/trunk/doc/html/pcre2test.html
code/trunk/doc/pcre2.txt
code/trunk/doc/pcre2test.txt
Modified: code/trunk/doc/html/pcre2_serialize_decode.html
===================================================================
--- code/trunk/doc/html/pcre2_serialize_decode.html 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/html/pcre2_serialize_decode.html 2015-09-12 18:12:01 UTC (rev 369)
@@ -20,7 +20,7 @@
</P>
<P>
<b>int32_t pcre2_serialize_decode(pcre2_code **<i>codes</i>,</b>
-<b> int32_t <i>number_of_codes</i>, const uint32_t *<i>bytes</i>,</b>
+<b> int32_t <i>number_of_codes</i>, const uint8_t *<i>bytes</i>,</b>
<b> pcre2_general_context *<i>gcontext</i>);</b>
</P>
<br><b>
Modified: code/trunk/doc/html/pcre2_serialize_encode.html
===================================================================
--- code/trunk/doc/html/pcre2_serialize_encode.html 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/html/pcre2_serialize_encode.html 2015-09-12 18:12:01 UTC (rev 369)
@@ -19,8 +19,8 @@
<b>#include <pcre2.h></b>
</P>
<P>
-<b>int32_t pcre2_serialize_encode(pcre2_code **<i>codes</i>,</b>
-<b> int32_t <i>number_of_codes</i>, uint32_t **<i>serialized_bytes</i>,</b>
+<b>int32_t pcre2_serialize_encode(const pcre2_code **<i>codes</i>,</b>
+<b> int32_t <i>number_of_codes</i>, uint8_t **<i>serialized_bytes</i>,</b>
<b> PCRE2_SIZE *<i>serialized_size</i>, pcre2_general_context *<i>gcontext</i>);</b>
</P>
<br><b>
Modified: code/trunk/doc/html/pcre2api.html
===================================================================
--- code/trunk/doc/html/pcre2api.html 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/html/pcre2api.html 2015-09-12 18:12:01 UTC (rev 369)
@@ -266,12 +266,12 @@
<br><a name="SEC9" href="#TOC1">PCRE2 NATIVE API SERIALIZATION FUNCTIONS</a><br>
<P>
<b>int32_t pcre2_serialize_decode(pcre2_code **<i>codes</i>,</b>
-<b> int32_t <i>number_of_codes</i>, const uint32_t *<i>bytes</i>,</b>
+<b> int32_t <i>number_of_codes</i>, const uint8_t *<i>bytes</i>,</b>
<b> pcre2_general_context *<i>gcontext</i>);</b>
<br>
<br>
-<b>int32_t pcre2_serialize_encode(pcre2_code **<i>codes</i>,</b>
-<b> int32_t <i>number_of_codes</i>, uint32_t **<i>serialized_bytes</i>,</b>
+<b>int32_t pcre2_serialize_encode(const pcre2_code **<i>codes</i>,</b>
+<b> int32_t <i>number_of_codes</i>, uint8_t **<i>serialized_bytes</i>,</b>
<b> PCRE2_SIZE *<i>serialized_size</i>, pcre2_general_context *<i>gcontext</i>);</b>
<br>
<br>
@@ -1091,7 +1091,10 @@
parenthesis. The name is not processed in any way, and it is not possible to
include a closing parenthesis in the name. However, if the PCRE2_ALT_VERBNAMES
option is set, normal backslash processing is applied to verb names and only an
-unescaped closing parenthesis terminates the name.
+unescaped closing parenthesis terminates the name. A closing parenthesis can be
+included in a name either as \) or between \Q and \E. If the PCRE2_EXTENDED
+option is set, unescaped whitespace in verb names is skipped and #-comments are
+recognized, exactly as in the rest of the pattern.
<pre>
PCRE2_AUTO_CALLOUT
</pre>
@@ -2909,7 +2912,7 @@
</P>
<br><a name="SEC40" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 30 August 2015
+Last updated: 02 September 2015
<br>
Copyright © 1997-2015 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcre2pattern.html
===================================================================
--- code/trunk/doc/html/pcre2pattern.html 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/html/pcre2pattern.html 2015-09-12 18:12:01 UTC (rev 369)
@@ -2925,7 +2925,10 @@
any way, and it is not possible to include a closing parenthesis in the name.
However, if the PCRE2_ALT_VERBNAMES option is set, normal backslash processing
is applied to verb names and only an unescaped closing parenthesis terminates
-the name.
+the name. A closing parenthesis can be included in a name either as \) or
+between \Q and \E. If the PCRE2_EXTENDED option is set, unescaped whitespace
+in verb names is skipped and #-comments are recognized, exactly as in the rest
+of the pattern.
</P>
<P>
The maximum length of a name is 255 in the 8-bit library and 65535 in the
@@ -3348,7 +3351,7 @@
</P>
<br><a name="SEC30" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 30 August 2015
+Last updated: 01 September 2015
<br>
Copyright © 1997-2015 University of Cambridge.
<br>
Modified: code/trunk/doc/html/pcre2posix.html
===================================================================
--- code/trunk/doc/html/pcre2posix.html 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/html/pcre2posix.html 2015-09-12 18:12:01 UTC (rev 369)
@@ -170,7 +170,7 @@
This area is not simple, because POSIX and Perl take different views of things.
It is not possible to get PCRE2 to obey POSIX semantics, but then PCRE2 was
never intended to be a POSIX engine. The following table lists the different
-possibilities for matching newline characters in PCRE2:
+possibilities for matching newline characters in Perl and PCRE2:
<pre>
Default Change with
@@ -180,7 +180,7 @@
$ matches \n in middle no PCRE2_MULTILINE
^ matches \n in middle no PCRE2_MULTILINE
</pre>
-This is the equivalent table for POSIX:
+This is the equivalent table for a POSIX-compatible pattern matcher:
<pre>
Default Change with
@@ -190,14 +190,18 @@
$ matches \n in middle no REG_NEWLINE
^ matches \n in middle no REG_NEWLINE
</pre>
-PCRE2's behaviour is the same as Perl's, except that there is no equivalent for
-PCRE2_DOLLAR_ENDONLY in Perl. In both PCRE2 and Perl, there is no way to stop
-newline from matching [^a].
+This behaviour is not what happens when PCRE2 is called via its POSIX
+API. By default, PCRE2's behaviour is the same as Perl's, except that there is
+no equivalent for PCRE2_DOLLAR_ENDONLY in Perl. In both PCRE2 and Perl, there
+is no way to stop newline from matching [^a].
</P>
<P>
-The default POSIX newline handling can be obtained by setting PCRE2_DOTALL and
-PCRE2_DOLLAR_ENDONLY, but there is no way to make PCRE2 behave exactly as for
-the REG_NEWLINE action.
+Default POSIX newline handling can be obtained by setting PCRE2_DOTALL and
+PCRE2_DOLLAR_ENDONLY when calling <b>pcre2_compile()</b> directly, but there is
+no way to make PCRE2 behave exactly as for the REG_NEWLINE action. When using
+the POSIX API, passing REG_NEWLINE to PCRE2's <b>regcomp()</b> function
+causes PCRE2_MULTILINE to be passed to <b>pcre2_compile()</b>, and REG_DOTALL
+passes PCRE2_DOTALL. There is no way to pass PCRE2_DOLLAR_ENDONLY.
</P>
<br><a name="SEC5" href="#TOC1">MATCHING A PATTERN</a><br>
<P>
@@ -283,9 +287,9 @@
</P>
<br><a name="SEC9" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 20 October 2014
+Last updated: 03 September 2015
<br>
-Copyright © 1997-2014 University of Cambridge.
+Copyright © 1997-2015 University of Cambridge.
<br>
<p>
Return to the <a href="index.html">PCRE2 index page</a>.
Modified: code/trunk/doc/html/pcre2test.html
===================================================================
--- code/trunk/doc/html/pcre2test.html 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/html/pcre2test.html 2015-09-12 18:12:01 UTC (rev 369)
@@ -305,6 +305,36 @@
described in the section entitled "Saving and restoring compiled patterns"
<a href="#saverestore">below.</a>
<pre>
+ #newline_default [<newline-list>]
+</pre>
+When PCRE2 is built, a default newline convention can be specified. This
+determines which characters and/or character pairs are recognized as indicating
+a newline in a pattern or subject string. The default can be overridden when a
+pattern is compiled. The standard test files contain tests of various newline
+conventions, but the majority of the tests expect a single linefeed to be
+recognized as a newline by default. Without special action the tests would fail
+when PCRE2 is compiled with either CR or CRLF as the default newline.
+</P>
+<P>
+The #newline_default command specifies a list of newline types that are
+acceptable as the default. The types must be one of CR, LF, CRLF, ANYCRLF, or
+ANY (in upper or lower case), for example:
+<pre>
+ #newline_default LF Any anyCRLF
+</pre>
+If the default newline is in the list, this command has no effect. Otherwise,
+except when testing the POSIX API, a <b>newline</b> modifier that specifies the
+first newline convention in the list (LF in the above example) is added to any
+pattern that does not already have a <b>newline</b> modifier. If the newline
+list is empty, the feature is turned off. This command is present in a number
+of the standard test input files.
+</P>
+<P>
+When the POSIX API is being tested there is no way to override the default
+newline convention, though it is possible to set the newline convention from
+within the pattern. A warning is given if the <b>posix</b> modifier is used when
+<b>#newline_default</b> would set a default for the non-POSIX API.
+<pre>
#pattern <modifier-list>
</pre>
This command sets a default modifier list that applies to all subsequent
@@ -480,7 +510,7 @@
allow_empty_class set PCRE2_ALLOW_EMPTY_CLASS
alt_bsux set PCRE2_ALT_BSUX
alt_circumflex set PCRE2_ALT_CIRCUMFLEX
- alt_verbnames set PCRE2_ALT_VERBNAMES
+ alt_verbnames set PCRE2_ALT_VERBNAMES
anchored set PCRE2_ANCHORED
auto_callout set PCRE2_AUTO_CALLOUT
/i caseless set PCRE2_CASELESS
@@ -625,21 +655,51 @@
JIT compilation
</b><br>
<P>
-The <b>/jit</b> modifier may optionally be followed by an equals sign and a
-number in the range 0 to 7:
+Just-in-time (JIT) compiling is a heavyweight optimization that can greatly
+speed up pattern matching. See the
+<a href="pcre2jit.html"><b>pcre2jit</b></a>
+documentation for details. JIT compiling happens, optionally, after a pattern
+has been successfully compiled into an internal form. The JIT compiler converts
+this to optimized machine code. It needs to know whether the match-time options
+PCRE2_PARTIAL_HARD and PCRE2_PARTIAL_SOFT are going to be used, because
+different code is generated for the different cases. See the <b>partial</b>
+modifier in "Subject Modifiers"
+<a href="#subjectmodifiers">below</a>
+for details of how these options are specified for each match attempt.
+</P>
+<P>
+JIT compilation is requested by the <b>/jit</b> pattern modifier, which may
+optionally be followed by an equals sign and a number in the range 0 to 7.
+The three bits that make up the number specify which of the three JIT operating
+modes are to be compiled:
<pre>
+ 1 compile JIT code for non-partial matching
+ 2 compile JIT code for soft partial matching
+ 4 compile JIT code for hard partial matching
+</pre>
+The possible values for the <b>/jit</b> modifier are therefore:
+<pre>
0 disable JIT
- 1 use JIT for normal match only
- 2 use JIT for soft partial match only
- 3 use JIT for normal match and soft partial match
- 4 use JIT for hard partial match only
- 6 use JIT for soft and hard partial match
+ 1 normal matching only
+ 2 soft partial matching only
+ 3 normal and soft partial matching
+ 4 hard partial matching only
+ 6 soft and hard partial matching only
7 all three modes
</pre>
-If no number is given, 7 is assumed. If JIT compilation is successful, the
-compiled JIT code will automatically be used when <b>pcre2_match()</b> is run
-for the appropriate type of match, except when incompatible run-time options
-are specified. For more details, see the
+If no number is given, 7 is assumed. The phrase "partial matching" means a call
+to <b>pcre2_match()</b> with either the PCRE2_PARTIAL_SOFT or the
+PCRE2_PARTIAL_HARD option set. Note that such a call may return a complete
+match; the options enable the possibility of a partial match, but do not
+require it. Note also that if you request JIT compilation only for partial
+matching (for example, /jit=2) but do not set the <b>partial</b> modifier on a
+subject line, that match will not use JIT code because none was compiled for
+non-partial matching.
+</P>
+<P>
+If JIT compilation is successful, the compiled JIT code will automatically be
+used when an appropriate type of match is run, except when incompatible
+run-time options are specified. For more details, see the
<a href="pcre2jit.html"><b>pcre2jit</b></a>
documentation. See also the <b>jitstack</b> modifier below for a way of
setting the size of the JIT stack.
@@ -707,8 +767,10 @@
<P>
The <b>/posix</b> modifier causes <b>pcre2test</b> to call PCRE2 via the POSIX
wrapper API rather than its native API. This supports only the 8-bit library.
-When the POSIX API is being used, the following pattern modifiers set options
-for the <b>regcomp()</b> function:
+Note that it does not imply POSIX matching semantics; for more detail see the
+<a href="pcre2posix.html"><b>pcre2posix</b></a>
+documentation. When the POSIX API is being used, the following pattern
+modifiers set options for the <b>regcomp()</b> function:
<pre>
caseless REG_ICASE
multiline REG_NEWLINE
@@ -790,7 +852,7 @@
warning message, except for <b>replace</b>, which causes an error. Note that,
<b>jitverify</b>, which is allowed, does not carry through to any subsequent
matching that uses this pattern.
-</P>
+<a name="subjectmodifiers"></a></P>
<br><a name="SEC11" href="#TOC1">SUBJECT MODIFIERS</a><br>
<P>
The modifiers that can appear in subject lines and the <b>#subject</b>
@@ -1471,7 +1533,7 @@
</P>
<br><a name="SEC21" href="#TOC1">REVISION</a><br>
<P>
-Last updated: 30 August 2015
+Last updated: 12 September 2015
<br>
Copyright © 1997-2015 University of Cambridge.
<br>
Modified: code/trunk/doc/pcre2.txt
===================================================================
--- code/trunk/doc/pcre2.txt 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/pcre2.txt 2015-09-12 18:12:01 UTC (rev 369)
@@ -356,11 +356,11 @@
PCRE2 NATIVE API SERIALIZATION FUNCTIONS
int32_t pcre2_serialize_decode(pcre2_code **codes,
- int32_t number_of_codes, const uint32_t *bytes,
+ int32_t number_of_codes, const uint8_t *bytes,
pcre2_general_context *gcontext);
- int32_t pcre2_serialize_encode(pcre2_code **codes,
- int32_t number_of_codes, uint32_t **serialized_bytes,
+ int32_t pcre2_serialize_encode(const pcre2_code **codes,
+ int32_t number_of_codes, uint8_t **serialized_bytes,
PCRE2_SIZE *serialized_size, pcre2_general_context *gcontext);
void pcre2_serialize_free(uint8_t *bytes);
@@ -1136,36 +1136,39 @@
and it is not possible to include a closing parenthesis in the name.
However, if the PCRE2_ALT_VERBNAMES option is set, normal backslash
processing is applied to verb names and only an unescaped closing
- parenthesis terminates the name.
+ parenthesis terminates the name. A closing parenthesis can be included
+ in a name either as \) or between \Q and \E. If the PCRE2_EXTENDED
+ option is set, unescaped whitespace in verb names is skipped and #-com-
+ ments are recognized, exactly as in the rest of the pattern.
PCRE2_AUTO_CALLOUT
- If this bit is set, pcre2_compile() automatically inserts callout
+ If this bit is set, pcre2_compile() automatically inserts callout
items, all with number 255, before each pattern item. For discussion of
the callout facility, see the pcre2callout documentation.
PCRE2_CASELESS
- If this bit is set, letters in the pattern match both upper and lower
- case letters in the subject. It is equivalent to Perl's /i option, and
+ If this bit is set, letters in the pattern match both upper and lower
+ case letters in the subject. It is equivalent to Perl's /i option, and
it can be changed within a pattern by a (?i) option setting.
PCRE2_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 PCRE2_DOLLAR_ENDONLY option is ignored
- if PCRE2_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 PCRE2_DOLLAR_ENDONLY option is ignored
+ if PCRE2_MULTILINE is set. There is no equivalent to this option in
Perl, and no way to set it within a pattern.
PCRE2_DOTALL
- If this bit is set, a dot metacharacter in the pattern matches any
- character, including one that indicates a newline. However, it only
+ If this bit is set, a dot metacharacter in the pattern matches any
+ character, including one that indicates a newline. However, it only
ever matches one character, even if newlines are coded as CRLF. Without
this option, a dot does not match when the current position in the sub-
- ject is at a newline. This option is equivalent to Perl's /s option,
+ ject 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 neg-
ative class such as [^a] always matches newline characters, independent
of the setting of this option.
@@ -1172,172 +1175,172 @@
PCRE2_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 pcre2pattern documentation.
PCRE2_EXTENDED
- If this bit is set, most white space characters in the pattern are
- totally ignored except when escaped or inside a character class. How-
- ever, white space is not allowed within sequences such as (?> that
+ If this bit is set, most white space characters in the pattern are
+ totally ignored except when escaped or inside a character class. How-
+ ever, white space is not allowed within sequences such as (?> that
introduce various parenthesized subpatterns, nor within numerical quan-
- tifiers such as {1,3}. Ignorable white space is permitted between an
- item and a following quantifier and between a quantifier and a follow-
+ tifiers such as {1,3}. Ignorable white space is permitted between an
+ item and a following quantifier and between a quantifier and a follow-
ing + that indicates possessiveness.
- PCRE2_EXTENDED also causes characters between an unescaped # outside a
- character class and the next newline, inclusive, to be ignored, which
+ PCRE2_EXTENDED also causes characters between an unescaped # outside a
+ character class and the next newline, inclusive, to be ignored, which
makes it possible to include comments inside complicated patterns. Note
- that the end of this type of comment is a literal newline sequence in
+ that the end of this type of comment is a literal newline sequence in
the pattern; escape sequences that happen to represent a newline do not
- count. PCRE2_EXTENDED is equivalent to Perl's /x option, and it can be
+ count. PCRE2_EXTENDED is equivalent to Perl's /x option, and it can be
changed within a pattern by a (?x) option setting.
Which characters are interpreted as newlines can be specified by a set-
- ting in the compile context that is passed to pcre2_compile() or by a
- special sequence at the start of the pattern, as described in the sec-
- tion entitled "Newline conventions" in the pcre2pattern documentation.
+ ting in the compile context that is passed to pcre2_compile() or by a
+ special sequence at the start of the pattern, as described in the sec-
+ tion entitled "Newline conventions" in the pcre2pattern documentation.
A default is defined when PCRE2 is built.
PCRE2_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.
PCRE2_MATCH_UNSET_BACKREF
- If this option is set, a back reference to an unset subpattern group
- matches an empty string (by default this causes the current matching
- alternative 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. Setting this option makes
+ If this option is set, a back reference to an unset subpattern group
+ matches an empty string (by default this causes the current matching
+ alternative 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. Setting this option makes
PCRE2 behave more like ECMAscript (aka JavaScript).
PCRE2_MULTILINE
- By default, for the purposes of matching "start of line" and "end of
- line", PCRE2 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, and
- the "end of line" metacharacter ($) matches only at the end of the
+ By default, for the purposes of matching "start of line" and "end of
+ line", PCRE2 treats the subject string as consisting of a single line
+ of characters, even if it actually contains newlines. The "start of
+ line" metacharacter (^) matches only at the start of the string, and
+ the "end of line" metacharacter ($) matches only at the end of the
string, or before a terminating newline (except when PCRE2_DOL-
- LAR_ENDONLY is set). Note, however, that unless PCRE2_DOTALL is set,
+ LAR_ENDONLY is set). Note, however, that unless PCRE2_DOTALL is set,
the "any character" metacharacter (.) does not match at a newline. This
behaviour (for ^, $, and dot) is the same as Perl.
- When PCRE2_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 PCRE2_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. Note that the "start
of line" metacharacter does not match after a newline at the end of the
- subject, for compatibility with Perl. However, you can change this by
- setting the PCRE2_ALT_CIRCUMFLEX option. If there are no newlines in a
- subject string, or no occurrences of ^ or $ in a pattern, setting
+ subject, for compatibility with Perl. However, you can change this by
+ setting the PCRE2_ALT_CIRCUMFLEX option. If there are no newlines in a
+ subject string, or no occurrences of ^ or $ in a pattern, setting
PCRE2_MULTILINE has no effect.
PCRE2_NEVER_BACKSLASH_C
- This option locks out the use of \C in the pattern that is being com-
- piled. This escape can cause unpredictable behaviour in UTF-8 or
- UTF-16 modes, because it may leave the current matching point in the
- middle of a multi-code-unit character. This option may be useful in
+ This option locks out the use of \C in the pattern that is being com-
+ piled. This escape can cause unpredictable behaviour in UTF-8 or
+ UTF-16 modes, because it may leave the current matching point in the
+ middle of a multi-code-unit character. This option may be useful in
applications that process patterns from external sources.
PCRE2_NEVER_UCP
- This option locks out the use of Unicode properties for handling \B,
+ This option locks out the use of Unicode properties for handling \B,
\b, \D, \d, \S, \s, \W, \w, and some of the POSIX character classes, as
- described for the PCRE2_UCP option below. In particular, it prevents
- the creator of the pattern from enabling this facility by starting the
- pattern with (*UCP). This option may be useful in applications that
+ described for the PCRE2_UCP option below. In particular, it prevents
+ the creator of the pattern from enabling this facility by starting the
+ pattern with (*UCP). This option may be useful in applications that
process patterns from external sources. The option combination PCRE_UCP
and PCRE_NEVER_UCP causes an error.
PCRE2_NEVER_UTF
- This option locks out interpretation of the pattern as UTF-8, UTF-16,
+ This option locks out interpretation of the pattern as UTF-8, UTF-16,
or UTF-32, depending on which library is in use. In particular, it pre-
- vents the creator of the pattern from switching to UTF interpretation
- by starting the pattern with (*UTF). This option may be useful in
- applications that process patterns from external sources. The combina-
+ vents the creator of the pattern from switching to UTF interpretation
+ by starting the pattern with (*UTF). This option may be useful in
+ applications that process patterns from external sources. The combina-
tion of PCRE2_UTF and PCRE2_NEVER_UTF causes an error.
PCRE2_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.
PCRE2_NO_AUTO_POSSESS
If this option is set, it disables "auto-possessification", which is an
- optimization that, for example, turns a+b into a++b in order to avoid
- backtracks into a+ that can never be successful. However, if callouts
- are in use, auto-possessification means that some callouts are never
+ optimization that, for example, turns a+b into a++b in order to avoid
+ backtracks into a+ that can never be successful. However, if callouts
+ are in use, auto-possessification means that some callouts are never
taken. You can set this option if you want the matching functions to do
- a full unoptimized search and run all the callouts, but it is mainly
+ a full unoptimized search and run all the callouts, but it is mainly
provided for testing purposes.
PCRE2_NO_DOTSTAR_ANCHOR
If this option is set, it disables an optimization that is applied when
- .* is the first significant item in a top-level branch of a pattern,
- and all the other branches also start with .* or with \A or \G or ^.
- The optimization is automatically disabled for .* if it is inside an
- atomic group or a capturing group that is the subject of a back refer-
- ence, or if the pattern contains (*PRUNE) or (*SKIP). When the opti-
- mization is not disabled, such a pattern is automatically anchored if
+ .* is the first significant item in a top-level branch of a pattern,
+ and all the other branches also start with .* or with \A or \G or ^.
+ The optimization is automatically disabled for .* if it is inside an
+ atomic group or a capturing group that is the subject of a back refer-
+ ence, or if the pattern contains (*PRUNE) or (*SKIP). When the opti-
+ mization is not disabled, such a pattern is automatically anchored if
PCRE2_DOTALL is set for all the .* items and PCRE2_MULTILINE is not set
- for any ^ items. Otherwise, the fact that any match must start either
- at the start of the subject or following a newline is remembered. Like
+ for any ^ items. Otherwise, the fact that any match must start either
+ at the start of the subject or following a newline is remembered. Like
other optimizations, this can cause callouts to be skipped.
PCRE2_NO_START_OPTIMIZE
- This is an option whose main effect is at matching time. It does not
+ This is an option whose main effect is at matching time. It does not
change what pcre2_compile() generates, but it does affect the output of
the JIT compiler.
- There are a number of optimizations that may occur at the start of a
- match, in order to speed up the process. For example, if it is known
- that an unanchored match must start with a specific character, the
- matching code searches the subject for that character, and fails imme-
- diately if it cannot find it, without actually running the main match-
- ing function. This means that a special item such as (*COMMIT) at the
- start of a pattern is not considered until after a suitable starting
- point for the match has been found. Also, when callouts or (*MARK)
- items are in use, these "start-up" optimizations can cause them to be
- skipped if the pattern is never actually used. The start-up optimiza-
- tions are in effect a pre-scan of the subject that takes place before
+ There are a number of optimizations that may occur at the start of a
+ match, in order to speed up the process. For example, if it is known
+ that an unanchored match must start with a specific character, the
+ matching code searches the subject for that character, and fails imme-
+ diately if it cannot find it, without actually running the main match-
+ ing function. This means that a special item such as (*COMMIT) at the
+ start of a pattern is not considered until after a suitable starting
+ point for the match has been found. Also, when callouts or (*MARK)
+ items are in use, these "start-up" optimizations can cause them to be
+ skipped if the pattern is never actually used. The start-up optimiza-
+ tions are in effect a pre-scan of the subject that takes place before
the pattern is run.
The PCRE2_NO_START_OPTIMIZE option disables the start-up optimizations,
- possibly causing performance to suffer, but ensuring that in cases
- where the result is "no match", the callouts do occur, and that items
+ possibly causing performance to suffer, but ensuring that in cases
+ where the result is "no match", the callouts do occur, and that items
such as (*COMMIT) and (*MARK) are considered at every possible starting
position in the subject string.
- Setting PCRE2_NO_START_OPTIMIZE may change the outcome of a matching
+ Setting PCRE2_NO_START_OPTIMIZE may change the outcome of a matching
operation. Consider the pattern
(*COMMIT)ABC
- When this is compiled, PCRE2 records the fact that a match must start
- with the character "A". Suppose the subject string is "DEFABC". The
- start-up optimization scans along the subject, finds "A" and runs the
- first match attempt from there. The (*COMMIT) item means that the pat-
- tern must match the current starting position, which in this case, it
- does. However, if the same match is run with PCRE2_NO_START_OPTIMIZE
- set, the initial scan along the subject string does not happen. The
- first match attempt is run starting from "D" and when this fails,
- (*COMMIT) prevents any further matches being tried, so the overall
+ When this is compiled, PCRE2 records the fact that a match must start
+ with the character "A". Suppose the subject string is "DEFABC". The
+ start-up optimization scans along the subject, finds "A" and runs the
+ first match attempt from there. The (*COMMIT) item means that the pat-
+ tern must match the current starting position, which in this case, it
+ does. However, if the same match is run with PCRE2_NO_START_OPTIMIZE
+ set, the initial scan along the subject string does not happen. The
+ first match attempt is run starting from "D" and when this fails,
+ (*COMMIT) prevents any further matches being tried, so the overall
result is "no match". There are also other start-up optimizations. For
example, a minimum length for the subject may be recorded. Consider the
pattern
@@ -1344,64 +1347,64 @@
(*MARK:A)(X|Y)
- The minimum length for a match is one character. If the subject is
+ The minimum length for a match is one character. If the subject is
"ABC", there will be attempts to match "ABC", "BC", and "C". An attempt
to match an empty string at the end of the subject does not take place,
- because PCRE2 knows that the subject is now too short, and so the
- (*MARK) is never encountered. In this case, the optimization does not
+ because PCRE2 knows that the subject is now too short, and so the
+ (*MARK) is never encountered. In this case, the optimization does not
affect the overall match result, which is still "no match", but it does
affect the auxiliary information that is returned.
PCRE2_NO_UTF_CHECK
- When PCRE2_UTF is set, the validity of the pattern as a UTF string is
- automatically checked. There are discussions about the validity of
- UTF-8 strings, UTF-16 strings, and UTF-32 strings in the pcre2unicode
+ When PCRE2_UTF is set, the validity of the pattern as a UTF string is
+ automatically checked. There are discussions about the validity of
+ UTF-8 strings, UTF-16 strings, and UTF-32 strings in the pcre2unicode
document. If an invalid UTF sequence is found, pcre2_compile() returns
a negative error code.
If you know that your pattern is valid, and you want to skip this check
- for performance reasons, you can set the PCRE2_NO_UTF_CHECK option.
- When it is set, the effect of passing an invalid UTF string as a pat-
- tern is undefined. It may cause your program to crash or loop. Note
- that this option can also be passed to pcre2_match() and
+ for performance reasons, you can set the PCRE2_NO_UTF_CHECK option.
+ When it is set, the effect of passing an invalid UTF string as a pat-
+ tern is undefined. It may cause your program to crash or loop. Note
+ that this option can also be passed to pcre2_match() and
pcre_dfa_match(), to suppress validity checking of the subject string.
PCRE2_UCP
This option changes the way PCRE2 processes \B, \b, \D, \d, \S, \s, \W,
- \w, and some of the POSIX character classes. By default, only ASCII
- characters are recognized, but if PCRE2_UCP is set, Unicode properties
- are used instead to classify characters. More details are given in the
+ \w, and some of the POSIX character classes. By default, only ASCII
+ characters are recognized, but if PCRE2_UCP is set, Unicode properties
+ are used instead to classify characters. More details are given in the
section on generic character types in the pcre2pattern page. If you set
- PCRE2_UCP, matching one of the items it affects takes much longer. The
- option is available only if PCRE2 has been compiled with Unicode sup-
+ PCRE2_UCP, matching one of the items it affects takes much longer. The
+ option is available only if PCRE2 has been compiled with Unicode sup-
port.
PCRE2_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.
PCRE2_UTF
- This option causes PCRE2 to regard both the pattern and the subject
- strings that are subsequently processed as strings of UTF characters
- instead of single-code-unit strings. It is available when PCRE2 is
- built to include Unicode support (which is the default). If Unicode
- support is not available, the use of this option provokes an error.
- Details of how this option changes the behaviour of PCRE2 are given in
+ This option causes PCRE2 to regard both the pattern and the subject
+ strings that are subsequently processed as strings of UTF characters
+ instead of single-code-unit strings. It is available when PCRE2 is
+ built to include Unicode support (which is the default). If Unicode
+ support is not available, the use of this option provokes an error.
+ Details of how this option changes the behaviour of PCRE2 are given in
the pcre2unicode page.
COMPILATION ERROR CODES
- There are over 80 positive error codes that pcre2_compile() may return
+ There are over 80 positive error codes that pcre2_compile() may return
if it finds an error in the pattern. There are also some negative error
- codes that are used for invalid UTF strings. These are the same as
- given by pcre2_match() and pcre2_dfa_match(), and are described in the
+ codes that are used for invalid UTF strings. These are the same as
+ given by pcre2_match() and pcre2_dfa_match(), and are described in the
pcre2unicode page. The pcre2_get_error_message() function can be called
to obtain a textual error message from any error code.
@@ -1425,53 +1428,53 @@
void pcre2_jit_stack_free(pcre2_jit_stack *jit_stack);
- These functions provide support for JIT compilation, which, if the
- just-in-time compiler is available, further processes a compiled pat-
+ These functions provide support for JIT compilation, which, if the
+ just-in-time compiler is available, further processes a compiled pat-
tern into machine code that executes much faster than the pcre2_match()
- interpretive matching function. Full details are given in the pcre2jit
+ interpretive matching function. Full details are given in the pcre2jit
documentation.
- JIT compilation is a heavyweight optimization. It can take some time
- for patterns to be analyzed, and for one-off matches and simple pat-
- terns the benefit of faster execution might be offset by a much slower
- compilation time. Most, but not all patterns can be optimized by the
+ JIT compilation is a heavyweight optimization. It can take some time
+ for patterns to be analyzed, and for one-off matches and simple pat-
+ terns the benefit of faster execution might be offset by a much slower
+ compilation time. Most, but not all patterns can be optimized by the
JIT compiler.
LOCALE SUPPORT
- PCRE2 handles caseless matching, and determines whether characters are
- letters, digits, or whatever, by reference to a set of tables, indexed
- by character code point. This applies only to characters whose code
- points are less than 256. By default, higher-valued code points never
- match escapes such as \w or \d. However, if PCRE2 is built with UTF
- support, all characters can be tested with \p and \P, or, alterna-
- tively, the PCRE2_UCP option can be set when a pattern is compiled;
- this causes \w and friends to use Unicode property support instead of
+ PCRE2 handles caseless matching, and determines whether characters are
+ letters, digits, or whatever, by reference to a set of tables, indexed
+ by character code point. This applies only to characters whose code
+ points are less than 256. By default, higher-valued code points never
+ match escapes such as \w or \d. However, if PCRE2 is built with UTF
+ support, all characters can be tested with \p and \P, or, alterna-
+ tively, the PCRE2_UCP option can be set when a pattern is compiled;
+ this causes \w and friends to use Unicode property support instead of
the built-in tables.
- The use of locales with Unicode is discouraged. If you are handling
- characters with code points greater than 128, you should either use
+ The use of locales with Unicode is discouraged. If you are handling
+ characters with code points greater than 128, you should either use
Unicode support, or use locales, but not try to mix the two.
- PCRE2 contains an internal set of character tables that are used by
- default. These are sufficient for many applications. Normally, the
+ PCRE2 contains an internal set of character tables that are used by
+ default. These are sufficient for many applications. Normally, the
internal tables recognize only ASCII characters. However, when PCRE2 is
built, it is possible to cause the internal tables to be rebuilt in the
default "C" locale of the local system, which may cause them to be dif-
ferent.
- The internal tables can be overridden by tables supplied by the appli-
- cation that calls PCRE2. These may be created in a different locale
- from the default. As more and more applications change to using Uni-
+ The internal tables can be overridden by tables supplied by the appli-
+ cation that calls PCRE2. These may be created in a different locale
+ 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 pcre2_maketables() function,
- in the relevant locale. The result can be passed to pcre2_compile() as
- often as necessary, by creating a compile context and calling
- pcre2_set_character_tables() to set the tables pointer therein. 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 pcre2_maketables() function,
+ in the relevant locale. The result can be passed to pcre2_compile() as
+ often as necessary, by creating a compile context and calling
+ pcre2_set_character_tables() to set the tables pointer therein. 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");
@@ -1480,15 +1483,15 @@
pcre2_set_character_tables(ccontext, tables);
re = pcre2_compile(..., ccontext);
- 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".
- It is the caller's responsibility to ensure that the memory containing
+ 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".
+ 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 (via the compile context) to pcre2_compile()
- is saved with the compiled pattern, and the same tables are used by
- pcre2_match() and pcre_dfa_match(). Thus, for any single pattern, com-
- pilation, and matching all happen in the same locale, but different
+ is saved with the compiled pattern, and the same tables are used by
+ pcre2_match() and pcre_dfa_match(). Thus, for any single pattern, com-
+ pilation, and matching all happen in the same locale, but different
patterns can be processed in different locales.
@@ -1496,13 +1499,13 @@
int pcre2_pattern_info(const pcre2 *code, uint32_t what, void *where);
- The pcre2_pattern_info() function returns general information about a
+ The pcre2_pattern_info() function returns general information about a
compiled pattern. For information about callouts, see the next section.
- The first argument for pcre2_pattern_info() is a pointer to the com-
+ The first argument for pcre2_pattern_info() is a pointer to the com-
piled pattern. The second argument specifies which piece of information
- is required, and the third argument is a pointer to a variable to
- receive the data. If the third argument is NULL, the first argument is
- ignored, and the function returns the size in bytes of the variable
+ is required, and the third argument is a pointer to a variable to
+ receive the data. If the third argument is NULL, the first argument is
+ ignored, and the function returns the size in bytes of the variable
that is required for the information requested. Otherwise, The yield of
the function is zero for success, or one of the following negative num-
bers:
@@ -1512,9 +1515,9 @@
PCRE2_ERROR_BADOPTION the value of what was invalid
PCRE2_ERROR_UNSET the requested field is not set
- 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 pcre2_pattern_info(), to obtain the length of the com-
+ 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 pcre2_pattern_info(), to obtain the length of the com-
piled pattern:
int rc;
@@ -1531,16 +1534,16 @@
PCRE2_INFO_ARGOPTIONS
Return a copy of the pattern's options. The third argument should point
- to a uint32_t variable. PCRE2_INFO_ARGOPTIONS returns exactly the
- options that were passed to pcre2_compile(), whereas PCRE2_INFO_ALLOP-
- TIONS returns the compile options as modified by any top-level option
- settings at the start of the pattern itself. In other words, they are
+ to a uint32_t variable. PCRE2_INFO_ARGOPTIONS returns exactly the
+ options that were passed to pcre2_compile(), whereas PCRE2_INFO_ALLOP-
+ TIONS returns the compile options as 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 PCRE2_EXTENDED
- option, the result is PCRE2_CASELESS, PCRE2_MULTILINE, and
+ option, the result is PCRE2_CASELESS, PCRE2_MULTILINE, and
PCRE2_EXTENDED.
- A pattern compiled without PCRE2_ANCHORED is automatically anchored by
+ A pattern compiled without PCRE2_ANCHORED is automatically anchored by
PCRE2 if the first significant item in every top-level branch is one of
the following:
@@ -1549,7 +1552,7 @@
\G always
.* sometimes - see below
- When .* is the first significant item, anchoring is possible only when
+ When .* is the first significant item, anchoring is possible only when
all the following are true:
.* is not in an atomic group
@@ -1559,18 +1562,18 @@
Neither (*PRUNE) nor (*SKIP) appears in the pattern.
PCRE2_NO_DOTSTAR_ANCHOR is not set.
- For patterns that are auto-anchored, the PCRE2_ANCHORED bit is set in
+ For patterns that are auto-anchored, the PCRE2_ANCHORED bit is set in
the options returned for PCRE2_INFO_ALLOPTIONS.
PCRE2_INFO_BACKREFMAX
- Return the number of the highest back reference in the pattern. The
- third argument should point to an uint32_t variable. Named subpatterns
- acquire numbers as well as names, and these count towards the highest
- back reference. Back references such as \4 or \g{12} match the cap-
- tured characters of the given group, but in addition, the check that a
+ Return the number of the highest back reference in the pattern. The
+ third argument should point to an uint32_t variable. Named subpatterns
+ acquire numbers as well as names, and these count towards the highest
+ back reference. Back references such as \4 or \g{12} match the cap-
+ tured characters of the given group, but in addition, the check that a
capturing group is set in a conditional subpattern such as (?(3)a|b) is
- also a back reference. Zero is returned if there are no back refer-
+ also a back reference. Zero is returned if there are no back refer-
ences.
PCRE2_INFO_BSR
@@ -1577,122 +1580,122 @@
The output is a uint32_t whose value indicates what character sequences
the \R escape sequence matches. A value of PCRE2_BSR_UNICODE means that
- \R matches any Unicode line ending sequence; a value of PCRE2_BSR_ANY-
+ \R matches any Unicode line ending sequence; a value of PCRE2_BSR_ANY-
CRLF means that \R matches only CR, LF, or CRLF.
PCRE2_INFO_CAPTURECOUNT
- Return the number of capturing subpatterns in the pattern. The third
+ Return the number of capturing subpatterns in the pattern. The third
argument should point to an uint32_t variable.
PCRE2_INFO_FIRSTCODETYPE
Return information about the first code unit of any matched string, for
- a non-anchored pattern. The third argument should point to an uint32_t
+ a non-anchored pattern. The third argument should point to an uint32_t
variable.
- If there is a fixed first value, for example, the letter "c" from a
- pattern such as (cat|cow|coyote), 1 is returned, and the character
- value can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no
- fixed first value, but it is known that a match can occur only at the
- start of the subject or following a newline in the subject, 2 is
+ If there is a fixed first value, for example, the letter "c" from a
+ pattern such as (cat|cow|coyote), 1 is returned, and the character
+ value can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no
+ fixed first value, but it is known that a match can occur only at the
+ start of the subject or following a newline in the subject, 2 is
returned. Otherwise, and for anchored patterns, 0 is returned.
PCRE2_INFO_FIRSTCODEUNIT
- Return the value of the first code unit of any matched string in the
+ Return the value of the first code unit of any matched string in the
situation where PCRE2_INFO_FIRSTCODETYPE returns 1; otherwise return 0.
- The third argument should point to an uint32_t variable. In the 8-bit
- library, the value is always less than 256. In the 16-bit library the
- value can be up to 0xffff. In the 32-bit library in UTF-32 mode the
+ The third argument should point to an uint32_t variable. In the 8-bit
+ library, the value is always less than 256. In the 16-bit library the
+ value can be up to 0xffff. In the 32-bit library in UTF-32 mode the
value can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32
mode.
PCRE2_INFO_FIRSTBITMAP
- In the absence of a single first code unit for a non-anchored pattern,
- pcre2_compile() may construct a 256-bit table that defines a fixed set
- of values for the first code unit in any match. For example, a pattern
- that starts with [abc] results in a table with three bits set. When
- code unit values greater than 255 are supported, the flag bit for 255
- means "any code unit of value 255 or above". If such a table was con-
- structed, a pointer to it is returned. Otherwise NULL is returned. The
+ In the absence of a single first code unit for a non-anchored pattern,
+ pcre2_compile() may construct a 256-bit table that defines a fixed set
+ of values for the first code unit in any match. For example, a pattern
+ that starts with [abc] results in a table with three bits set. When
+ code unit values greater than 255 are supported, the flag bit for 255
+ means "any code unit of value 255 or above". If such a table was con-
+ structed, a pointer to it is returned. Otherwise NULL is returned. The
third argument should point to an const uint8_t * variable.
PCRE2_INFO_HASCRORLF
- Return 1 if the pattern contains any explicit matches for CR or LF
+ Return 1 if the pattern contains any explicit matches for CR or LF
characters, otherwise 0. The third argument should point to an uint32_t
- variable. An explicit match is either a literal CR or LF character, or
+ variable. An explicit match is either a literal CR or LF character, or
\r or \n.
PCRE2_INFO_JCHANGED
- Return 1 if the (?J) or (?-J) option setting is used in the pattern,
- otherwise 0. The third argument should point to an uint32_t variable.
- (?J) and (?-J) set and unset the local PCRE2_DUPNAMES option, respec-
+ Return 1 if the (?J) or (?-J) option setting is used in the pattern,
+ otherwise 0. The third argument should point to an uint32_t variable.
+ (?J) and (?-J) set and unset the local PCRE2_DUPNAMES option, respec-
tively.
PCRE2_INFO_JITSIZE
- If the compiled pattern was successfully processed by pcre2_jit_com-
- pile(), return the size of the JIT compiled code, otherwise return
+ If the compiled pattern was successfully processed by pcre2_jit_com-
+ pile(), return the size of the JIT compiled code, otherwise return
zero. The third argument should point to a size_t variable.
PCRE2_INFO_LASTCODETYPE
- Returns 1 if there is a rightmost literal code unit that must exist in
- any matched string, other than at its start. The third argument should
- point to an uint32_t variable. If there is no such value, 0 is
- returned. When 1 is returned, the code unit value itself can be
+ Returns 1 if there is a rightmost literal code unit that must exist in
+ any matched string, other than at its start. The third argument should
+ point to an uint32_t variable. If there is no such value, 0 is
+ returned. When 1 is returned, the code unit value itself can be
retrieved using PCRE2_INFO_LASTCODEUNIT.
For anchored patterns, a last literal value is recorded only if it fol-
- lows something of variable length. For example, for the pattern
- /^a\d+z\d+/ the returned value is 1 (with "z" returned from
+ lows something of variable length. For example, for the pattern
+ /^a\d+z\d+/ the returned value is 1 (with "z" returned from
PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value is 0.
PCRE2_INFO_LASTCODEUNIT
- Return the value of the rightmost literal data unit that must exist in
- any matched string, other than at its start, if such a value has been
- recorded. The third argument should point to an uint32_t variable. If
+ Return the value of the rightmost literal data unit that must exist in
+ any matched string, other than at its start, if such a value has been
+ recorded. The third argument should point to an uint32_t variable. If
there is no such value, 0 is returned.
PCRE2_INFO_MATCHEMPTY
- Return 1 if the pattern can match an empty string, otherwise 0. The
+ Return 1 if the pattern can match an empty string, otherwise 0. The
third argument should point to an uint32_t variable.
PCRE2_INFO_MATCHLIMIT
- If the pattern set a match limit by including an item of the form
- (*LIMIT_MATCH=nnnn) at the start, the value is returned. The third
- argument should point to an unsigned 32-bit integer. If no such value
- has been set, the call to pcre2_pattern_info() returns the error
+ If the pattern set a match limit by including an item of the form
+ (*LIMIT_MATCH=nnnn) at the start, the value is returned. The third
+ argument should point to an unsigned 32-bit integer. If no such value
+ has been set, the call to pcre2_pattern_info() returns the error
PCRE2_ERROR_UNSET.
PCRE2_INFO_MAXLOOKBEHIND
Return the number of characters (not code units) in the longest lookbe-
- hind assertion in the pattern. The third argument should point to an
- unsigned 32-bit integer. This information is useful when doing multi-
- segment matching using the partial matching facilities. Note that the
+ hind assertion in the pattern. The third argument should point to an
+ unsigned 32-bit integer. This information is useful when doing multi-
+ segment matching using the partial matching facilities. Note that the
simple assertions \b and \B require a one-character lookbehind. \A also
- registers a one-character lookbehind, though it does not actually
- inspect the previous character. This is to ensure that at least one
- character from the old segment is retained when a new segment is pro-
+ registers a one-character lookbehind, though it does not actually
+ inspect the previous character. This is to ensure that at least one
+ character from the old segment is retained when a new segment is pro-
cessed. Otherwise, if there are no lookbehinds in the pattern, \A might
match incorrectly at the start of a new segment.
PCRE2_INFO_MINLENGTH
- If a minimum length for matching subject strings was computed, its
- value is returned. Otherwise the returned value is 0. The value is a
- number of characters, which in UTF mode may be different from the num-
- ber of code units. The third argument should point to an uint32_t
- variable. The value is a lower bound to the length of any matching
- string. There may not be any strings of that length that do actually
+ If a minimum length for matching subject strings was computed, its
+ value is returned. Otherwise the returned value is 0. The value is a
+ number of characters, which in UTF mode may be different from the num-
+ ber of code units. The third argument should point to an uint32_t
+ variable. The value is a lower bound to the length of any matching
+ string. There may not be any strings of that length that do actually
match, but every string that does match is at least that long.
PCRE2_INFO_NAMECOUNT
@@ -1700,50 +1703,50 @@
PCRE2_INFO_NAMETABLE
PCRE2 supports the use of named as well as numbered capturing parenthe-
- ses. The names are just an additional way of identifying the parenthe-
+ ses. The names are just an additional way of identifying the parenthe-
ses, which still acquire numbers. Several convenience functions such as
- pcre2_substring_get_byname() 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 pcre2_match() below). To
- do the conversion, you need to use the name-to-number map, which is
+ pcre2_substring_get_byname() 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 pcre2_match() below). To
+ do 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. PCRE2_INFO_NAME-
- COUNT gives the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives
- the size of each entry in code units; both of these return a uint32_t
+ The map consists of a number of fixed-size entries. PCRE2_INFO_NAME-
+ COUNT gives the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives
+ the size of each entry in code units; both of these return a uint32_t
value. The entry size depends on the length of the longest name.
PCRE2_INFO_NAMETABLE returns a pointer to the first entry of the table.
- This is a PCRE2_SPTR pointer to a block of code units. In the 8-bit
- library, the first two bytes of each entry are the number of the cap-
+ This is a PCRE2_SPTR pointer to a block of code units. In the 8-bit
+ library, the first two bytes of each entry are the number of the cap-
turing parenthesis, most significant byte first. In the 16-bit library,
- the pointer points to 16-bit code units, the first of which contains
- the parenthesis number. In the 32-bit library, the pointer points to
- 32-bit code units, the first of which contains the parenthesis number.
+ the pointer points to 16-bit code units, the first of which contains
+ the parenthesis number. In the 32-bit library, the pointer points to
+ 32-bit code units, the first of which contains the parenthesis number.
The rest of the entry is the corresponding name, zero terminated.
- The names are in alphabetical order. If (?| is used to create multiple
- groups with the same number, as described in the section on duplicate
- subpattern numbers in the pcre2pattern page, the groups may be given
- the same name, but there is only one entry in the table. Different
+ The names are in alphabetical order. If (?| is used to create multiple
+ groups with the same number, as described in the section on duplicate
+ subpattern numbers in the pcre2pattern page, the groups may be given
+ the same name, but there is only one entry in the table. Different
names for groups of the same number are not permitted.
- Duplicate names for subpatterns with different numbers are permitted,
- but only if PCRE2_DUPNAMES is set. They appear in the table in the
- order in which they were found in the pattern. In the absence of (?|
- this is the order of increasing number; when (?| is used this is not
+ Duplicate names for subpatterns with different numbers are permitted,
+ but only if PCRE2_DUPNAMES is set. They appear in the table in the
+ order in which they were found in the pattern. In the absence of (?|
+ this is the order of increasing number; when (?| is used this is not
necessarily the case because later subpatterns may have lower numbers.
- As a simple example of the name/number table, consider the following
- pattern after compilation by the 8-bit library (assume PCRE2_EXTENDED
+ As a simple example of the name/number table, consider the following
+ pattern after compilation by the 8-bit library (assume PCRE2_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 ??:
@@ -1752,8 +1755,8 @@
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.
PCRE2_INFO_NEWLINE
@@ -1766,27 +1769,27 @@
PCRE2_NEWLINE_ANY Any Unicode line ending
PCRE2_NEWLINE_ANYCRLF Any of CR, LF, or CRLF
- This specifies the default character sequence that will be recognized
+ This specifies the default character sequence that will be recognized
as meaning "newline" while matching.
PCRE2_INFO_RECURSIONLIMIT
- If the pattern set a recursion limit by including an item of the form
- (*LIMIT_RECURSION=nnnn) at the start, the value is returned. The third
- argument should point to an unsigned 32-bit integer. If no such value
- has been set, the call to pcre2_pattern_info() returns the error
+ If the pattern set a recursion limit by including an item of the form
+ (*LIMIT_RECURSION=nnnn) at the start, the value is returned. The third
+ argument should point to an unsigned 32-bit integer. If no such value
+ has been set, the call to pcre2_pattern_info() returns the error
PCRE2_ERROR_UNSET.
PCRE2_INFO_SIZE
- Return the size of the compiled pattern in bytes (for all three
- libraries). The third argument should point to a size_t variable. This
- value includes the size of the general data block that precedes the
- code units of the compiled pattern itself. The value that is used when
- pcre2_compile() is getting memory in which to place the compiled pat-
- tern may be slightly larger than the value returned by this option,
- because there are cases where the code that calculates the size has to
- over-estimate. Processing a pattern with the JIT compiler does not
+ Return the size of the compiled pattern in bytes (for all three
+ libraries). The third argument should point to a size_t variable. This
+ value includes the size of the general data block that precedes the
+ code units of the compiled pattern itself. The value that is used when
+ pcre2_compile() is getting memory in which to place the compiled pat-
+ tern may be slightly larger than the value returned by this option,
+ because there are cases where the code that calculates the size has to
+ over-estimate. Processing a pattern with the JIT compiler does not
alter the value returned by this option.
@@ -1797,22 +1800,22 @@
void *user_data);
A script language that supports the use of string arguments in callouts
- might like to scan all the callouts in a pattern before running the
+ might like to scan all the callouts in a pattern before running the
match. This can be done by calling pcre2_callout_enumerate(). The first
- argument is a pointer to a compiled pattern, the second points to a
- callback function, and the third is arbitrary user data. The callback
- function is called for every callout in the pattern in the order in
+ argument is a pointer to a compiled pattern, the second points to a
+ callback function, and the third is arbitrary user data. The callback
+ function is called for every callout in the pattern in the order in
which they appear. Its first argument is a pointer to a callout enumer-
- ation block, and its second argument is the user_data value that was
- passed to pcre2_callout_enumerate(). The contents of the callout enu-
- meration block are described in the pcre2callout documentation, which
+ ation block, and its second argument is the user_data value that was
+ passed to pcre2_callout_enumerate(). The contents of the callout enu-
+ meration block are described in the pcre2callout documentation, which
also gives further details about callouts.
SERIALIZATION AND PRECOMPILING
- It is possible to save compiled patterns on disc or elsewhere, and
- reload them later, subject to a number of restrictions. The functions
+ It is possible to save compiled patterns on disc or elsewhere, and
+ reload them later, subject to a number of restrictions. The functions
whose names begin with pcre2_serialize_ are used for this purpose. They
are described in the pcre2serialize documentation.
@@ -1827,56 +1830,56 @@
void pcre2_match_data_free(pcre2_match_data *match_data);
- Information about a successful or unsuccessful match is placed in a
- match data block, which is an opaque structure that is accessed by
- function calls. In particular, the match data block contains a vector
- of offsets into the subject string that define the matched part of the
- subject and any substrings that were captured. This is know as the
+ Information about a successful or unsuccessful match is placed in a
+ match data block, which is an opaque structure that is accessed by
+ function calls. In particular, the match data block contains a vector
+ of offsets into the subject string that define the matched part of the
+ subject and any substrings that were captured. This is know as the
ovector.
- Before calling pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match()
+ Before calling pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match()
you must create a match data block by calling one of the creation func-
- tions above. For pcre2_match_data_create(), the first argument is the
- number of pairs of offsets in the ovector. One pair of offsets is
- required to identify the string that matched the whole pattern, with
- another pair for each captured substring. For example, a value of 4
- creates enough space to record the matched portion of the subject plus
- three captured substrings. A minimum of at least 1 pair is imposed by
+ tions above. For pcre2_match_data_create(), the first argument is the
+ number of pairs of offsets in the ovector. One pair of offsets is
+ required to identify the string that matched the whole pattern, with
+ another pair for each captured substring. For example, a value of 4
+ creates enough space to record the matched portion of the subject plus
+ three captured substrings. A minimum of at least 1 pair is imposed by
pcre2_match_data_create(), so it is always possible to return the over-
all matched string.
The second argument of pcre2_match_data_create() is a pointer to a gen-
- eral context, which can specify custom memory management for obtaining
+ eral context, which can specify custom memory management for obtaining
the memory for the match data block. If you are not using custom memory
management, pass NULL, which causes malloc() to be used.
- For pcre2_match_data_create_from_pattern(), the first argument is a
+ For pcre2_match_data_create_from_pattern(), the first argument is a
pointer to a compiled pattern. The ovector is created to be exactly the
right size to hold all the substrings a pattern might capture. The sec-
- ond argument is again a pointer to a general context, but in this case
+ ond argument is again a pointer to a general context, but in this case
if NULL is passed, the memory is obtained using the same allocator that
was used for the compiled pattern (custom or default).
- A match data block can be used many times, with the same or different
- compiled patterns. You can extract information from a match data block
+ A match data block can be used many times, with the same or different
+ compiled patterns. You can extract information from a match data block
after a match operation has finished, using functions that are
- described in the sections on matched strings and other match data
+ described in the sections on matched strings and other match data
below.
- When a call of pcre2_match() fails, valid data is available in the
- match block only when the error is PCRE2_ERROR_NOMATCH,
- PCRE2_ERROR_PARTIAL, or one of the error codes for an invalid UTF
+ When a call of pcre2_match() fails, valid data is available in the
+ match block only when the error is PCRE2_ERROR_NOMATCH,
+ PCRE2_ERROR_PARTIAL, or one of the error codes for an invalid UTF
string. Exactly what is available depends on the error, and is detailed
below.
- When one of the matching functions is called, pointers to the compiled
- pattern and the subject string are set in the match data block so that
- they can be referenced by the extraction functions. After running a
- match, you must not free a compiled pattern or a subject string until
- after all operations on the match data block (for that match) have
+ When one of the matching functions is called, pointers to the compiled
+ pattern and the subject string are set in the match data block so that
+ they can be referenced by the extraction functions. After running a
+ match, you must not free a compiled pattern or a subject string until
+ after all operations on the match data block (for that match) have
taken place.
- When a match data block itself is no longer needed, it should be freed
+ When a match data block itself is no longer needed, it should be freed
by calling pcre2_match_data_free().
@@ -1887,15 +1890,15 @@
uint32_t options, pcre2_match_data *match_data,
pcre2_match_context *mcontext);
- The function pcre2_match() is called to match a subject string against
- a compiled pattern, which is passed in the code argument. You can call
+ The function pcre2_match() is called to match a subject string against
+ a compiled pattern, which is passed in the code argument. You can call
pcre2_match() with the same code argument as many times as you like, in
- order to find multiple matches in the subject string or to match dif-
+ order to find multiple matches in the subject string or to match dif-
ferent subject strings with the same pattern.
- 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 section
+ 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 section
about the pcre2_dfa_match() function.
Here is an example of a simple call to pcre2_match():
@@ -1910,7 +1913,7 @@
match_data, /* the match data block */
NULL); /* a match context; NULL means use defaults */
- If the subject string is zero-terminated, the length can be given as
+ If the subject string is zero-terminated, the length can be given as
PCRE2_ZERO_TERMINATED. A match context must be provided if certain less
common matching parameters are to be changed. For details, see the sec-
tion on the match context above.
@@ -1917,67 +1920,67 @@
The string to be matched by pcre2_match()
- The subject string is passed to pcre2_match() as a pointer in subject,
- a length in length, and a starting offset in startoffset. The length
- and offset are in code units, not characters. That is, they are in
- bytes for the 8-bit library, 16-bit code units for the 16-bit library,
- and 32-bit code units for the 32-bit library, whether or not UTF pro-
+ The subject string is passed to pcre2_match() as a pointer in subject,
+ a length in length, and a starting offset in startoffset. The length
+ and offset are in code units, not characters. That is, they are in
+ bytes for the 8-bit library, 16-bit code units for the 16-bit library,
+ and 32-bit code units for the 32-bit library, whether or not UTF pro-
cessing is enabled.
If startoffset is greater than the length of the subject, pcre2_match()
- returns PCRE2_ERROR_BADOFFSET. When the starting offset is zero, the
- search for a match starts at the beginning of the subject, and this is
+ returns PCRE2_ERROR_BADOFFSET. 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. In UTF-8 or UTF-16 mode, the starting off-
- set must point to the start of a character, or to the end of the sub-
- ject (in UTF-32 mode, one code unit equals one character, so all off-
- sets are valid). Like the pattern string, the subject may contain
+ set must point to the start of a character, or to the end of the sub-
+ ject (in UTF-32 mode, one code unit equals one character, so all off-
+ sets are valid). Like the pattern string, the subject may contain
binary zeroes.
- A non-zero starting offset is useful when searching for another match
- in the same subject by calling pcre2_match() again after a previous
- success. Setting startoffset differs from passing over a shortened
- string and setting PCRE2_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 pcre2_match() again after a previous
+ success. Setting startoffset differs from passing over a shortened
+ string and setting PCRE2_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.)
+ 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 pcre2_match()
- finds the first occurrence. If pcre2_match() is called again with just
- the remainder of the subject, namely "issipi", it does not match,
+ finds the first occurrence. If pcre2_match() 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 pcre2_match() is passed the entire
+ to be a word boundary. However, if pcre2_match() 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.
- Finding all the matches in a subject is tricky when the pattern can
+ Finding all the matches in a subject is tricky when the pattern can
match an empty string. It is possible to emulate Perl's /g behaviour by
- first trying the match again at the same offset, with the
- PCRE2_NOTEMPTY_ATSTART and PCRE2_ANCHORED options, and then if that
- fails, advancing the starting offset and trying an ordinary match
- again. There is some code that demonstrates how to do this in the
- pcre2demo sample program. In the most general case, you have to check
- to see if the newline convention recognizes CRLF as a newline, and if
- so, and the current character is CR followed by LF, advance the start-
+ first trying the match again at the same offset, with the
+ PCRE2_NOTEMPTY_ATSTART and PCRE2_ANCHORED options, and then if that
+ fails, advancing the starting offset and trying an ordinary match
+ again. There is some code that demonstrates how to do this in the
+ pcre2demo sample program. In the most general case, you have to check
+ to see if the newline convention recognizes CRLF as a newline, and if
+ so, and the current character is CR followed by LF, advance the start-
ing offset by two characters instead of one.
- 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.
Option bits for pcre2_match()
The unused bits of the options argument for pcre2_match() must be zero.
- The only bits that may be set are PCRE2_ANCHORED, PCRE2_NOTBOL,
+ The only bits that may be set are PCRE2_ANCHORED, PCRE2_NOTBOL,
PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART,
- PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. Their
+ PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and PCRE2_PARTIAL_SOFT. Their
action is described below.
- Setting PCRE2_ANCHORED at match time is not supported by the just-in-
- time (JIT) compiler. If it is set, JIT matching is disabled and the
+ Setting PCRE2_ANCHORED at match time is not supported by the just-in-
+ time (JIT) compiler. If it is set, JIT matching is disabled and the
normal interpretive code in pcre2_match() is run. The remaining options
are supported for JIT matching.
@@ -1984,16 +1987,16 @@
PCRE2_ANCHORED
The PCRE2_ANCHORED option limits pcre2_match() to matching at the first
- matching position. If a pattern was compiled with PCRE2_ANCHORED, or
- turned out to be anchored by virtue of its contents, it cannot be made
- unachored at matching time. Note that setting the option at match time
+ matching position. If a pattern was compiled with PCRE2_ANCHORED, or
+ turned out to be anchored by virtue of its contents, it cannot be made
+ unachored at matching time. Note that setting the option at match time
disables JIT matching.
PCRE2_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 having set PCRE2_MULTILINE at
+ the beginning of a line, so the circumflex metacharacter should not
+ match before it. Setting this without having set PCRE2_MULTILINE at
compile time causes circumflex never to match. This option affects only
the behaviour of the circumflex metacharacter. It does not affect \A.
@@ -2000,9 +2003,9 @@
PCRE2_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-
- out having set PCRE2_MULTILINE at compile time causes dollar never to
+ 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 having set PCRE2_MULTILINE at compile time causes dollar never to
match. This option affects only the behaviour of the dollar metacharac-
ter. It does not affect \Z or \z.
@@ -2009,72 +2012,72 @@
PCRE2_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 an
+ is applied to a string not beginning with "a" or "b", it matches an
empty string at the start of the subject. With PCRE2_NOTEMPTY set, this
- match is not valid, so pcre2_match() searches further into the string
+ match is not valid, so pcre2_match() searches further into the string
for occurrences of "a" or "b".
PCRE2_NOTEMPTY_ATSTART
- This is like PCRE2_NOTEMPTY, except that it locks out an empty string
+ This is like PCRE2_NOTEMPTY, except that it locks out an empty string
match only at the first matching position, that is, at the start of the
- subject plus the starting offset. An empty string match later in the
- subject is permitted. If the pattern is anchored, such a match can
+ subject plus the starting offset. An empty string match later in the
+ subject is permitted. If the pattern is anchored, such a match can
occur only if the pattern contains \K.
PCRE2_NO_UTF_CHECK
When PCRE2_UTF is set at compile time, the validity of the subject as a
- UTF string is checked by default when pcre2_match() is subsequently
- called. If a non-zero starting offset is given, the check is applied
- only to that part of the subject that could be inspected during match-
- ing, and there is a check that the starting offset points to the first
- code unit of a character or to the end of the subject. If there are no
- lookbehind assertions in the pattern, the check starts at the starting
- offset. Otherwise, it starts at the length of the longest lookbehind
+ UTF string is checked by default when pcre2_match() is subsequently
+ called. If a non-zero starting offset is given, the check is applied
+ only to that part of the subject that could be inspected during match-
+ ing, and there is a check that the starting offset points to the first
+ code unit of a character or to the end of the subject. If there are no
+ lookbehind assertions in the pattern, the check starts at the starting
+ offset. Otherwise, it starts at the length of the longest lookbehind
before the starting offset, or at the start of the subject if there are
- not that many characters before the starting offset. Note that the
+ not that many characters before the starting offset. Note that the
sequences \b and \B are one-character lookbehinds.
The check is carried out before any other processing takes place, and a
- negative error code is returned if the check fails. There are several
- UTF error codes for each code unit width, corresponding to different
- problems with the code unit sequence. There are discussions about the
- validity of UTF-8 strings, UTF-16 strings, and UTF-32 strings in the
+ negative error code is returned if the check fails. There are several
+ UTF error codes for each code unit width, corresponding to different
+ problems with the code unit sequence. There are discussions about the
+ validity of UTF-8 strings, UTF-16 strings, and UTF-32 strings in the
pcre2unicode page.
- If you know that your subject is valid, and you want to skip these
- checks for performance reasons, you can set the PCRE2_NO_UTF_CHECK
- option when calling pcre2_match(). You might want to do this for the
+ If you know that your subject is valid, and you want to skip these
+ checks for performance reasons, you can set the PCRE2_NO_UTF_CHECK
+ option when calling pcre2_match(). You might want to do this for the
second and subsequent calls to pcre2_match() if you are making repeated
calls to find all the matches in a single subject string.
- NOTE: When PCRE2_NO_UTF_CHECK is set, the effect of passing an invalid
- string as a subject, or an invalid value of startoffset, is undefined.
+ NOTE: When PCRE2_NO_UTF_CHECK is set, the effect of passing an invalid
+ string as a subject, or an invalid value of startoffset, is undefined.
Your program may crash or loop indefinitely.
PCRE2_PARTIAL_HARD
PCRE2_PARTIAL_SOFT
- These options turn on the partial matching feature. A partial match
- occurs if the end of the subject string is reached successfully, but
- there are not enough subject characters to complete the match. If this
- happens when PCRE2_PARTIAL_SOFT (but not PCRE2_PARTIAL_HARD) is set,
- matching continues by testing any remaining alternatives. Only if no
- complete match can be found is PCRE2_ERROR_PARTIAL returned instead of
- PCRE2_ERROR_NOMATCH. In other words, PCRE2_PARTIAL_SOFT specifies that
- the caller is prepared to handle a partial match, but only if no com-
+ These options turn on the partial matching feature. A partial match
+ occurs if the end of the subject string is reached successfully, but
+ there are not enough subject characters to complete the match. If this
+ happens when PCRE2_PARTIAL_SOFT (but not PCRE2_PARTIAL_HARD) is set,
+ matching continues by testing any remaining alternatives. Only if no
+ complete match can be found is PCRE2_ERROR_PARTIAL returned instead of
+ PCRE2_ERROR_NOMATCH. In other words, PCRE2_PARTIAL_SOFT specifies that
+ the caller is prepared to handle a partial match, but only if no com-
plete match can be found.
- If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this
- case, if a partial match is found, pcre2_match() immediately returns
- PCRE2_ERROR_PARTIAL, without considering any other alternatives. In
+ If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this
+ case, if a partial match is found, pcre2_match() immediately returns
+ PCRE2_ERROR_PARTIAL, without considering any other alternatives. In
other words, when PCRE2_PARTIAL_HARD is set, a partial match is consid-
ered to be more important that an alternative complete match.
@@ -2084,34 +2087,34 @@
NEWLINE HANDLING WHEN MATCHING
- When PCRE2 is built, a default newline convention is set; this is usu-
- ally the standard convention for the operating system. The default can
- be overridden in a compile context. During matching, the newline
- choice affects the behaviour of the dot, circumflex, and dollar
- metacharacters. It may also alter the way the match starting position
+ When PCRE2 is built, a default newline convention is set; this is usu-
+ ally the standard convention for the operating system. The default can
+ be overridden in a compile context. During matching, the newline
+ choice affects the behaviour of the dot, circumflex, and dollar
+ metacharacters. It may also alter the way the match starting position
is advanced after a match failure for an unanchored pattern.
When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is
- set as the newline convention, and a match attempt for an unanchored
+ set as the newline convention, and a match attempt for an unanchored
pattern fails when the current starting 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
+ 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 PCRE2_DOTALL
+ expected. For example, if the pattern is .+A (and the PCRE2_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 in the pattern, or one of the \r or \n escape
- sequences. Implicit matches such as [^X] do not count, nor does \s,
+ those characters in the pattern, or one of the \r or \n escape
+ sequences. Implicit matches such as [^X] do not count, nor does \s,
even though it 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.
@@ -2122,84 +2125,84 @@
PCRE2_SIZE *pcre2_get_ovector_pointer(pcre2_match_data *match_data);
- In general, a pattern matches a certain portion of the subject, and in
- addition, further substrings from the subject may be picked out by
- parenthesized parts of the pattern. Following the usage in Jeffrey
- Friedl's book, this is called "capturing" in what follows, and the
- phrase "capturing subpattern" or "capturing group" is used for a frag-
- ment of a pattern that picks out a substring. PCRE2 supports several
+ In general, a pattern matches a certain portion of the subject, and in
+ addition, further substrings from the subject may be picked out by
+ parenthesized parts of the pattern. Following the usage in Jeffrey
+ Friedl's book, this is called "capturing" in what follows, and the
+ phrase "capturing subpattern" or "capturing group" is used for a frag-
+ ment of a pattern that picks out a substring. PCRE2 supports several
other kinds of parenthesized subpattern that do not cause substrings to
- be captured. The pcre2_pattern_info() function can be used to find out
+ be captured. The pcre2_pattern_info() function can be used to find out
how many capturing subpatterns there are in a compiled pattern.
- A successful match returns the overall matched string and any captured
- substrings to the caller via a vector of PCRE2_SIZE values. This is
- called the ovector, and is contained within the match data block. You
- can obtain direct access to the ovector by calling pcre2_get_ovec-
- tor_pointer() to find its address, and pcre2_get_ovector_count() to
- find the number of pairs of values it contains. Alternatively, you can
+ A successful match returns the overall matched string and any captured
+ substrings to the caller via a vector of PCRE2_SIZE values. This is
+ called the ovector, and is contained within the match data block. You
+ can obtain direct access to the ovector by calling pcre2_get_ovec-
+ tor_pointer() to find its address, and pcre2_get_ovector_count() to
+ find the number of pairs of values it contains. Alternatively, you can
use the auxiliary functions for accessing captured substrings by number
or by name (see below).
Within the ovector, the first in each pair of values is set to the off-
set of the first code unit of a substring, and the second is set to the
- offset of the first code unit after the end of a substring. These val-
- ues are always code unit offsets, not character offsets. That is, they
- are byte offsets in the 8-bit library, 16-bit offsets in the 16-bit
+ offset of the first code unit after the end of a substring. These val-
+ ues are always code unit offsets, not character offsets. That is, they
+ are byte offsets in the 8-bit library, 16-bit offsets in the 16-bit
library, and 32-bit offsets in the 32-bit library.
- After a partial match (error return PCRE2_ERROR_PARTIAL), only the
- first pair of offsets (that is, ovector[0] and ovector[1]) are set.
- They identify the part of the subject that was partially matched. See
+ After a partial match (error return PCRE2_ERROR_PARTIAL), only the
+ first pair of offsets (that is, ovector[0] and ovector[1]) are set.
+ They identify the part of the subject that was partially matched. See
the pcre2partial documentation for details of partial matching.
After a successful match, the first pair of offsets identifies the por-
- tion of the subject string that was matched by the entire pattern. The
- next pair is used for the first capturing subpattern, and so on. The
- value returned by pcre2_match() is one more than the highest numbered
- pair that has been set. For example, if two substrings have been cap-
- tured, the returned value is 3. If there are no capturing subpatterns,
+ tion of the subject string that was matched by the entire pattern. The
+ next pair is used for the first capturing subpattern, and so on. The
+ value returned by pcre2_match() is one more than the highest numbered
+ pair that has been set. For example, if two substrings have been cap-
+ tured, 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 pattern uses the \K escape sequence within a positive assertion,
+ If a pattern uses the \K escape sequence within a positive assertion,
the reported start of a successful match can be greater than the end of
- the match. For example, if the pattern (?=ab\K) is matched against
+ the match. For example, if the pattern (?=ab\K) is matched against
"ab", the start and end offset values for the match are 2 and 0.
- If a capturing subpattern group is matched repeatedly within a single
- match operation, it is the last portion of the subject that it matched
+ If a capturing subpattern group is matched repeatedly within a single
+ match operation, it is the last portion of the subject that it matched
that is returned.
If the ovector is too small to hold all the captured substring offsets,
- as much as possible is filled in, and the function returns a value of
- zero. If captured substrings are not of interest, pcre2_match() may be
+ as much as possible is filled in, and the function returns a value of
+ zero. If captured substrings are not of interest, pcre2_match() may be
called with a match data block whose ovector is of minimum length (that
is, one pair). However, if the pattern contains back references and the
ovector is not big enough to remember the related substrings, PCRE2 has
- to get additional memory for use during matching. Thus it is usually
+ to get additional memory for use during matching. Thus it is usually
advisable to set up a match data block containing an ovector of reason-
able size.
- 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 PCRE2_UNSET.
- Offset values that correspond to unused subpatterns at the end of the
- expression are also set to PCRE2_UNSET. For example, if the string
+ Offset values that correspond to unused subpatterns at the end of the
+ expression are also set to PCRE2_UNSET. 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 high-
+ are not matched. The return from the function is 2, because the high-
est used capturing subpattern number is 1. The offsets for for the sec-
- ond and third capturing subpatterns (assuming the vector is large
+ ond and third capturing subpatterns (assuming the vector is large
enough, of course) are set to PCRE2_UNSET.
Elements in the ovector that do not correspond to capturing parentheses
in the pattern are never changed. That is, if a pattern contains n cap-
turing parentheses, no more than ovector[0] to ovector[2n+1] are set by
- pcre2_match(). The other elements retain whatever values they previ-
+ pcre2_match(). The other elements retain whatever values they previ-
ously had.
@@ -2209,37 +2212,37 @@
PCRE2_SIZE pcre2_get_startchar(pcre2_match_data *match_data);
- As well as the offsets in the ovector, other information about a match
- is retained in the match data block and can be retrieved by the above
- functions in appropriate circumstances. If they are called at other
+ As well as the offsets in the ovector, other information about a match
+ is retained in the match data block and can be retrieved by the above
+ functions in appropriate circumstances. If they are called at other
times, the result is undefined.
- After a successful match, a partial match (PCRE2_ERROR_PARTIAL), or a
- failure to match (PCRE2_ERROR_NOMATCH), a (*MARK) name may be avail-
- able, and pcre2_get_mark() can be called. It returns a pointer to the
- zero-terminated name, which is within the compiled pattern. Otherwise
- NULL is returned. After a successful match, the (*MARK) name that is
- returned is the last one encountered on the matching path through the
- pattern. After a "no match" or a partial match, the last encountered
+ After a successful match, a partial match (PCRE2_ERROR_PARTIAL), or a
+ failure to match (PCRE2_ERROR_NOMATCH), a (*MARK) name may be avail-
+ able, and pcre2_get_mark() can be called. It returns a pointer to the
+ zero-terminated name, which is within the compiled pattern. Otherwise
+ NULL is returned. After a successful match, the (*MARK) name that is
+ returned is the last one encountered on the matching path through the
+ pattern. After a "no match" or a partial match, the last encountered
(*MARK) name is returned. For example, consider this pattern:
^(*MARK:A)((*MARK:B)a|b)c
- When it matches "bc", the returned mark is A. The B mark is "seen" in
- the first branch of the group, but it is not on the matching path. On
- the other hand, when this pattern fails to match "bx", the returned
+ When it matches "bc", the returned mark is A. The B mark is "seen" in
+ the first branch of the group, but it is not on the matching path. On
+ the other hand, when this pattern fails to match "bx", the returned
mark is B.
- After a successful match, a partial match, or one of the invalid UTF
- errors (for example, PCRE2_ERROR_UTF8_ERR5), pcre2_get_startchar() can
+ After a successful match, a partial match, or one of the invalid UTF
+ errors (for example, PCRE2_ERROR_UTF8_ERR5), pcre2_get_startchar() can
be called. After a successful or partial match it returns the code unit
- offset of the character at which the match started. For a non-partial
- match, this can be different to the value of ovector[0] if the pattern
- contains the \K escape sequence. After a partial match, however, this
- value is always the same as ovector[0] because \K does not affect the
+ offset of the character at which the match started. For a non-partial
+ match, this can be different to the value of ovector[0] if the pattern
+ contains the \K escape sequence. After a partial match, however, this
+ value is always the same as ovector[0] because \K does not affect the
result of a partial match.
- After a UTF check failure, pcre2_get_startchar() can be used to obtain
+ After a UTF check failure, pcre2_get_startchar() can be used to obtain
the code unit offset of the invalid UTF character. Details are given in
the pcre2unicode page.
@@ -2246,12 +2249,12 @@
ERROR RETURNS FROM pcre2_match()
- If pcre2_match() fails, it returns a negative number. This can be con-
- verted to a text string by calling pcre2_get_error_message(). Negative
- error codes are also returned by other functions, and are documented
+ If pcre2_match() fails, it returns a negative number. This can be con-
+ verted to a text string by calling pcre2_get_error_message(). Negative
+ error codes are also returned by other functions, and are documented
with them. The codes are given names in the header file. If UTF check-
ing is in force and an invalid UTF subject string is detected, one of a
- number of UTF-specific negative error codes is returned. Details are
+ number of UTF-specific negative error codes is returned. Details are
given in the pcre2unicode page. The following are the other errors that
may be returned by pcre2_match():
@@ -2261,19 +2264,19 @@
PCRE2_ERROR_PARTIAL
- 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
pcre2partial documentation for details of partial matching.
PCRE2_ERROR_BADMAGIC
PCRE2 stores a 4-byte "magic number" at the start of the compiled code,
- to catch the case when it is passed a junk pointer. This is the error
+ to catch the case when it is passed a junk pointer. This is the error
that is returned when the magic number is not present.
PCRE2_ERROR_BADMODE
- This error is given when a pattern that was compiled by the 8-bit
- library is passed to a 16-bit or 32-bit library function, or vice
+ This error is given when a pattern that was compiled by the 8-bit
+ library is passed to a 16-bit or 32-bit library function, or vice
versa.
PCRE2_ERROR_BADOFFSET
@@ -2287,35 +2290,35 @@
PCRE2_ERROR_BADUTFOFFSET
The UTF code unit sequence that was passed as a subject was checked and
- found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the
- value of startoffset did not point to the beginning of a UTF character
+ found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the
+ value of startoffset did not point to the beginning of a UTF character
or the end of the subject.
PCRE2_ERROR_CALLOUT
- This error is never generated by pcre2_match() itself. It is provided
- for use by callout functions that want to cause pcre2_match() or
- pcre2_callout_enumerate() to return a distinctive error code. See the
+ This error is never generated by pcre2_match() itself. It is provided
+ for use by callout functions that want to cause pcre2_match() or
+ pcre2_callout_enumerate() to return a distinctive error code. See the
pcre2callout documentation for details.
PCRE2_ERROR_INTERNAL
- 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 PCRE2 or by overwriting of the compiled pattern.
PCRE2_ERROR_JIT_BADOPTION
- This error is returned when a pattern that was successfully studied
- using JIT is being matched, but the matching mode (partial or complete
- match) does not correspond to any JIT compilation mode. When the JIT
- fast path function is used, this error may be also given for invalid
+ This error is returned when a pattern that was successfully studied
+ using JIT is being matched, but the matching mode (partial or complete
+ match) does not correspond to any JIT compilation mode. When the JIT
+ fast path function is used, this error may be also given for invalid
options. See the pcre2jit documentation for more details.
PCRE2_ERROR_JIT_STACKLIMIT
- This error is returned when a pattern that was successfully studied
- using JIT is being matched, but the memory available for the just-in-
- time processing stack is not large enough. See the pcre2jit documenta-
+ This error is returned when a pattern that was successfully studied
+ using JIT is being matched, but the memory available for the just-in-
+ time processing stack is not large enough. See the pcre2jit documenta-
tion for more details.
PCRE2_ERROR_MATCHLIMIT
@@ -2324,10 +2327,10 @@
PCRE2_ERROR_NOMEMORY
- If a pattern contains back references, but the ovector is not big
- enough to remember the referenced substrings, PCRE2 gets a block of
+ If a pattern contains back references, but the ovector is not big
+ enough to remember the referenced substrings, PCRE2 gets a block of
memory at the start of matching to use for this purpose. There are some
- other special cases where extra memory is needed during matching. This
+ other special cases where extra memory is needed during matching. This
error is given when memory cannot be obtained.
PCRE2_ERROR_NULL
@@ -2336,12 +2339,12 @@
PCRE2_ERROR_RECURSELOOP
- This error is returned when pcre2_match() detects a recursion loop
- within the pattern. Specifically, it means that either the whole pat-
+ This error is returned when pcre2_match() detects a recursion loop
+ within the pattern. Specifically, it means that either the whole pat-
tern or a subpattern has been called recursively for the second time at
- the same position in the subject string. Some simple patterns that
- might do this are detected and faulted at compile time, but more com-
- plicated cases, in particular mutual recursions between two different
+ the same position in the subject string. Some simple patterns that
+ might do this are detected and faulted at compile time, but more com-
+ plicated cases, in particular mutual recursions between two different
subpatterns, cannot be detected until matching is attempted.
PCRE2_ERROR_RECURSIONLIMIT
@@ -2364,39 +2367,39 @@
void pcre2_substring_free(PCRE2_UCHAR *buffer);
- Captured substrings can be accessed directly by using the ovector as
+ Captured substrings can be accessed directly by using the ovector as
described above. For convenience, auxiliary functions are provided for
- extracting captured substrings as new, separate, zero-terminated
+ extracting captured substrings as new, separate, zero-terminated
strings. 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
+ and has a further zero added on the end, but the result is not, of
course, a C string.
The functions in this section identify substrings by number. The number
zero refers to the entire matched substring, with higher numbers refer-
- ring to substrings captured by parenthesized groups. After a partial
- match, only substring zero is available. An attempt to extract any
- other substring gives the error PCRE2_ERROR_PARTIAL. The next section
+ ring to substrings captured by parenthesized groups. After a partial
+ match, only substring zero is available. An attempt to extract any
+ other substring gives the error PCRE2_ERROR_PARTIAL. The next section
describes similar functions for extracting captured substrings by name.
- If a pattern uses the \K escape sequence within a positive assertion,
+ If a pattern uses the \K escape sequence within a positive assertion,
the reported start of a successful match can be greater than the end of
- the match. For example, if the pattern (?=ab\K) is matched against
- "ab", the start and end offset values for the match are 2 and 0. In
- this situation, calling these functions with a zero substring number
+ the match. For example, if the pattern (?=ab\K) is matched against
+ "ab", the start and end offset values for the match are 2 and 0. In
+ this situation, calling these functions with a zero substring number
extracts a zero-length empty string.
- You can find the length in code units of a captured substring without
- extracting it by calling pcre2_substring_length_bynumber(). The first
- argument is a pointer to the match data block, the second is the group
- number, and the third is a pointer to a variable into which the length
- is placed. If you just want to know whether or not the substring has
+ You can find the length in code units of a captured substring without
+ extracting it by calling pcre2_substring_length_bynumber(). The first
+ argument is a pointer to the match data block, the second is the group
+ number, and the third is a pointer to a variable into which the length
+ is placed. If you just want to know whether or not the substring has
been captured, you can pass the third argument as NULL.
- The pcre2_substring_copy_bynumber() function copies a captured sub-
- string into a supplied buffer, whereas pcre2_substring_get_bynumber()
- copies it into new memory, obtained using the same memory allocation
- function that was used for the match data block. The first two argu-
- ments of these functions are a pointer to the match data block and a
+ The pcre2_substring_copy_bynumber() function copies a captured sub-
+ string into a supplied buffer, whereas pcre2_substring_get_bynumber()
+ copies it into new memory, obtained using the same memory allocation
+ function that was used for the match data block. The first two argu-
+ ments of these functions are a pointer to the match data block and a
capturing group number.
The final arguments of pcre2_substring_copy_bynumber() are a pointer to
@@ -2405,25 +2408,25 @@
for the extracted substring, excluding the terminating zero.
For pcre2_substring_get_bynumber() the third and fourth arguments point
- to variables that are updated with a pointer to the new memory and the
- number of code units that comprise the substring, again excluding the
- terminating zero. When the substring is no longer needed, the memory
+ to variables that are updated with a pointer to the new memory and the
+ number of code units that comprise the substring, again excluding the
+ terminating zero. When the substring is no longer needed, the memory
should be freed by calling pcre2_substring_free().
- The return value from all these functions is zero for success, or a
- negative error code. If the pattern match failed, the match failure
- code is returned. If a substring number greater than zero is used
- after a partial match, PCRE2_ERROR_PARTIAL is returned. Other possible
+ The return value from all these functions is zero for success, or a
+ negative error code. If the pattern match failed, the match failure
+ code is returned. If a substring number greater than zero is used
+ after a partial match, PCRE2_ERROR_PARTIAL is returned. Other possible
error codes are:
PCRE2_ERROR_NOMEMORY
- The buffer was too small for pcre2_substring_copy_bynumber(), or the
+ The buffer was too small for pcre2_substring_copy_bynumber(), or the
attempt to get memory failed for pcre2_substring_get_bynumber().
PCRE2_ERROR_NOSUBSTRING
- There is no substring with that number in the pattern, that is, the
+ There is no substring with that number in the pattern, that is, the
number is greater than the number of capturing parentheses.
PCRE2_ERROR_UNAVAILABLE
@@ -2434,8 +2437,8 @@
PCRE2_ERROR_UNSET
- The substring did not participate in the match. For example, if the
- pattern is (abc)|(def) and the subject is "def", and the ovector con-
+ The substring did not participate in the match. For example, if the
+ pattern is (abc)|(def) and the subject is "def", and the ovector con-
tains at least two capturing slots, substring number 1 is unset.
@@ -2446,32 +2449,32 @@
void pcre2_substring_list_free(PCRE2_SPTR *list);
- The pcre2_substring_list_get() function extracts all available sub-
- strings and builds a list of pointers to them. It also (optionally)
- builds a second list that contains their lengths (in code units),
+ The pcre2_substring_list_get() function extracts all available sub-
+ strings and builds a list of pointers to them. It also (optionally)
+ builds a second list that contains their lengths (in code units),
excluding a terminating zero that is added to each of them. All this is
done in a single block of memory that is obtained using the same memory
allocation function that was used to get the match data block.
- This function must be called only after a successful match. If called
+ This function must be called only after a successful match. If called
after a partial match, the error code PCRE2_ERROR_PARTIAL is returned.
- The address of the memory block is returned via listptr, which is also
+ 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 address of the list of lengths is returned via
- lengthsptr. If your strings do not contain binary zeros and you do not
+ by a NULL pointer. The address of the list of lengths is returned via
+ lengthsptr. If your strings do not contain binary zeros and you do not
therefore need the lengths, you may supply NULL as the lengthsptr argu-
- ment to disable the creation of a list of lengths. The yield of the
- function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem-
- ory block could not be obtained. When the list is no longer needed, it
+ ment to disable the creation of a list of lengths. The yield of the
+ function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem-
+ ory block could not be obtained. When the list is no longer needed, it
should be freed by calling pcre2_substring_list_free().
If this function encounters 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, it returns an empty string.
- This can be distinguished from a genuine zero-length substring by
+ when capturing subpattern number n+1 matches some part of the subject,
+ but subpattern n has not been used at all, it returns an empty string.
+ This can be distinguished from a genuine zero-length substring by
inspecting the appropriate offset in the ovector, which contain
- PCRE2_UNSET for unset substrings, or by calling pcre2_sub-
+ PCRE2_UNSET for unset substrings, or by calling pcre2_sub-
string_length_bynumber().
@@ -2491,39 +2494,39 @@
void pcre2_substring_free(PCRE2_UCHAR *buffer);
- 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+)...
the number of the subpattern called "xxx" is 2. If the name is known to
- be unique (PCRE2_DUPNAMES was not set), you can find the number from
+ be unique (PCRE2_DUPNAMES was not set), you can find the number from
the name by calling pcre2_substring_number_from_name(). The first argu-
- ment is the compiled pattern, and the second is the name. The yield of
+ ment is the compiled pattern, and the second is the name. The yield of
the function is the subpattern number, PCRE2_ERROR_NOSUBSTRING if there
- is no subpattern of that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if
- there is more than one subpattern of that name. Given the number, you
- can extract the substring directly, or use one of the functions
+ is no subpattern of that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if
+ there is more than one subpattern of that name. Given the number, you
+ can extract the substring directly, or use one of the functions
described above.
- For convenience, there are also "byname" functions that correspond to
- the "bynumber" functions, the only difference being that the second
- argument is a name instead of a number. If PCRE2_DUPNAMES is set and
+ For convenience, there are also "byname" functions that correspond to
+ the "bynumber" functions, the only difference being that the second
+ argument is a name instead of a number. If PCRE2_DUPNAMES is set and
there are duplicate names, these functions scan all the groups with the
given name, and return the first named string that is set.
- If there are no groups with the given name, PCRE2_ERROR_NOSUBSTRING is
- returned. If all groups with the name have numbers that are greater
- than the number of slots in the ovector, PCRE2_ERROR_UNAVAILABLE is
- returned. If there is at least one group with a slot in the ovector,
+ If there are no groups with the given name, PCRE2_ERROR_NOSUBSTRING is
+ returned. If all groups with the name have numbers that are greater
+ than the number of slots in the ovector, PCRE2_ERROR_UNAVAILABLE is
+ returned. If there is at least one group with a slot in the ovector,
but no group is found to be set, PCRE2_ERROR_UNSET is returned.
Warning: If the pattern uses the (?| feature to set up multiple subpat-
- terns with the same number, as described in the section on duplicate
- subpattern numbers in the pcre2pattern page, you cannot use names to
- distinguish the different subpatterns, because names are not included
- in the compiled code. The matching process uses only numbers. For this
- reason, the use of different names for subpatterns of the same number
+ terns with the same number, as described in the section on duplicate
+ subpattern numbers in the pcre2pattern page, you cannot use names to
+ distinguish the different subpatterns, because names are not included
+ in the compiled code. The matching process uses only numbers. For this
+ reason, the use of different names for subpatterns of the same number
causes an error at compile time.
@@ -2535,15 +2538,15 @@
pcre2_match_context *mcontext, PCRE2_SPTR replacementzfP,
PCRE2_SIZE rlength, PCRE2_UCHAR *outputbufferP,
PCRE2_SIZE *outlengthptr);
- This function calls pcre2_match() and then makes a copy of the subject
- string in outputbuffer, replacing the part that was matched with the
- replacement string, whose length is supplied in rlength. This can be
+ This function calls pcre2_match() and then makes a copy of the subject
+ string in outputbuffer, replacing the part that was matched with the
+ replacement string, whose length is supplied in rlength. This can be
given as PCRE2_ZERO_TERMINATED for a zero-terminated string.
- In the replacement string, which is interpreted as a UTF string in UTF
- mode, and is checked for UTF validity unless the PCRE2_NO_UTF_CHECK
+ In the replacement string, which is interpreted as a UTF string in UTF
+ mode, and is checked for UTF validity unless the PCRE2_NO_UTF_CHECK
option is set, a dollar character is an escape character that can spec-
- ify the insertion of characters from capturing groups or (*MARK) items
+ ify the insertion of characters from capturing groups or (*MARK) items
in the pattern. The following forms are recognized:
$$ insert a dollar character
@@ -2550,12 +2553,12 @@
$<n> or ${<n>} insert the contents of group <n>
$*MARK or ${*MARK} insert the name of the last (*MARK) encountered
- Either a group number or a group name can be given for <n>. Curly
- brackets are required only if the following character would be inter-
+ Either a group number or a group name can be given for <n>. Curly
+ brackets are required only if the following character would be inter-
preted as part of the number or name. The number may be zero to include
- the entire matched string. For example, if the pattern a(b)c is
- matched with "=abc=" and the replacement string "+$1$0$1+", the result
- is "=+babcb+=". Group insertion is done by calling pcre2_copy_byname()
+ the entire matched string. For example, if the pattern a(b)c is
+ matched with "=abc=" and the replacement string "+$1$0$1+", the result
+ is "=+babcb+=". Group insertion is done by calling pcre2_copy_byname()
or pcre2_copy_bynumber() as appropriate.
The facility for inserting a (*MARK) name can be used to perform simple
@@ -2565,30 +2568,30 @@
apple lemon
2: pear orange
- The first seven arguments of pcre2_substitute() are the same as for
+ The first seven arguments of pcre2_substitute() are the same as for
pcre2_match(), except that the partial matching options are not permit-
- ted, and match_data may be passed as NULL, in which case a match data
- block is obtained and freed within this function, using memory manage-
- ment functions from the match context, if provided, or else those that
+ ted, and match_data may be passed as NULL, in which case a match data
+ block is obtained and freed within this function, using memory manage-
+ ment functions from the match context, if provided, or else those that
were used to allocate memory for the compiled code.
- There is one additional option, PCRE2_SUBSTITUTE_GLOBAL, which causes
+ There is one additional option, PCRE2_SUBSTITUTE_GLOBAL, which causes
the function to iterate over the subject string, replacing every match-
ing substring. If this is not set, only the first matching substring is
replaced.
- The outlengthptr argument must point to a variable that contains the
- length, in code units, of the output buffer. It is updated to contain
+ The outlengthptr argument must point to a variable that contains the
+ length, in code units, of the output buffer. It is updated to contain
the length of the new string, excluding the trailing zero that is auto-
matically added.
- The function returns the number of replacements that were made. This
- may be zero if no matches were found, and is never greater than 1
+ The function returns the number of replacements that were made. This
+ may be zero if no matches were found, and is never greater than 1
unless PCRE2_SUBSTITUTE_GLOBAL is set. In the event of an error, a neg-
- ative error code is returned. Except for PCRE2_ERROR_NOMATCH (which is
+ ative error code is returned. Except for PCRE2_ERROR_NOMATCH (which is
never returned), any errors from pcre2_match() or the substring copying
functions are passed straight back. PCRE2_ERROR_BADREPLACEMENT is
- returned for an invalid replacement string (unrecognized sequence fol-
+ returned for an invalid replacement string (unrecognized sequence fol-
lowing a dollar sign), and PCRE2_ERROR_NOMEMORY is returned if the out-
put buffer is not big enough.
@@ -2598,38 +2601,38 @@
int pcre2_substring_nametable_scan(const pcre2_code *code,
PCRE2_SPTR name, PCRE2_SPTR *first, PCRE2_SPTR *last);
- When a pattern is compiled with the PCRE2_DUPNAMES option, names for
- subpatterns are not required to be unique. Duplicate names are always
- allowed for subpatterns with the same number, created by using the (?|
- feature. Indeed, if such subpatterns are named, they are required to
+ When a pattern is compiled with the PCRE2_DUPNAMES option, names for
+ subpatterns are not required to be unique. Duplicate names are always
+ allowed for subpatterns with the same number, created by using the (?|
+ feature. Indeed, if such subpatterns are named, they are required to
use the same names.
Normally, patterns with duplicate names are such that in any one match,
- only one of the named subpatterns participates. An example is shown in
+ only one of the named subpatterns participates. An example is shown in
the pcre2pattern documentation.
- When duplicates are present, pcre2_substring_copy_byname() and
- pcre2_substring_get_byname() return the first substring corresponding
- to the given name that is set. Only if none are set is
- PCRE2_ERROR_UNSET is returned. The pcre2_substring_number_from_name()
+ When duplicates are present, pcre2_substring_copy_byname() and
+ pcre2_substring_get_byname() return the first substring corresponding
+ to the given name that is set. Only if none are set is
+ PCRE2_ERROR_UNSET is returned. The pcre2_substring_number_from_name()
function returns the error PCRE2_ERROR_NOUNIQUESUBSTRING when there are
duplicate names.
- If you want to get full details of all captured substrings for a given
- name, you must use the pcre2_substring_nametable_scan() function. The
- first argument is the compiled pattern, and the second is the name. If
- the third and fourth arguments are NULL, the function returns a group
+ If you want to get full details of all captured substrings for a given
+ name, you must use the pcre2_substring_nametable_scan() function. The
+ first argument is the compiled pattern, and the second is the name. If
+ the third and fourth arguments are NULL, the function returns a group
number for a unique name, or PCRE2_ERROR_NOUNIQUESUBSTRING otherwise.
When the third and fourth arguments are not NULL, they must be pointers
- to variables that are updated by the function. After it has run, they
+ to variables that 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, and the function returns the length of each entry in code
- units. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there are
+ given name, and the function returns the length of each entry in code
+ units. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there are
no entries for the given name.
The format of the name table is described above in the section entitled
- Information about a pattern above. Given all the relevant entries for
+ Information about a pattern above. Given all the relevant entries for
the name, you can extract each of their numbers, and hence the captured
data.
@@ -2636,18 +2639,18 @@
FINDING ALL POSSIBLE MATCHES AT ONE POSITION
- The traditional matching function uses a similar algorithm to Perl,
- which stops when it finds the first match at a given point in the sub-
+ The traditional matching function uses a similar algorithm to Perl,
+ which stops when it finds the first match at a given point in the sub-
ject. If you want to find all possible matches, or the longest possible
- match at a given position, consider using the alternative matching
- function (see below) instead. If you cannot use the alternative func-
+ match at a given position, consider using the alternative matching
+ function (see below) instead. If you cannot use the alternative func-
tion, you can kludge it up by making use of the callout facility, which
is described in the pcre2callout documentation.
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 pcre2_match() 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 pcre2_match() to
+ backtrack and try other alternatives. Ultimately, when it runs out of
matches, pcre2_match() will yield PCRE2_ERROR_NOMATCH.
@@ -2659,26 +2662,26 @@
pcre2_match_context *mcontext,
int *workspace, PCRE2_SIZE wscount);
- The function pcre2_dfa_match() 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 PCRE2 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, and a list of features
+ The function pcre2_dfa_match() 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 PCRE2 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, and a list of features
that pcre2_dfa_match() does not support, see the pcre2matching documen-
tation.
- The arguments for the pcre2_dfa_match() function are the same as for
+ The arguments for the pcre2_dfa_match() function are the same as for
pcre2_match(), plus two extras. The ovector within the match data block
is used in a different way, and this is described below. The other com-
- mon arguments are used in the same way as for pcre2_match(), so their
+ mon arguments are used in the same way as for pcre2_match(), 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 is needed for patterns and subjects where there are a lot of
+ workspace is needed for patterns and subjects where there are a lot of
potential matches.
Here is an example of a simple call to pcre2_dfa_match():
@@ -2698,45 +2701,45 @@
Option bits for pcre_dfa_match()
- The unused bits of the options argument for pcre2_dfa_match() must be
- zero. The only bits that may be set are PCRE2_ANCHORED, PCRE2_NOTBOL,
+ The unused bits of the options argument for pcre2_dfa_match() must be
+ zero. The only bits that may be set are PCRE2_ANCHORED, PCRE2_NOTBOL,
PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART,
PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, PCRE2_PARTIAL_SOFT,
- PCRE2_DFA_SHORTEST, and PCRE2_DFA_RESTART. All but the last four of
- these are exactly the same as for pcre2_match(), so their description
+ PCRE2_DFA_SHORTEST, and PCRE2_DFA_RESTART. All but the last four of
+ these are exactly the same as for pcre2_match(), so their description
is not repeated here.
PCRE2_PARTIAL_HARD
PCRE2_PARTIAL_SOFT
- These have the same general effect as they do for pcre2_match(), but
- the details are slightly different. When PCRE2_PARTIAL_HARD is set for
- pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if the end of the
+ These have the same general effect as they do for pcre2_match(), but
+ the details are slightly different. When PCRE2_PARTIAL_HARD is set for
+ pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if the end of the
subject is reached and there is still at least one matching possibility
that requires additional characters. This happens even if some complete
- matches have already been found. When PCRE2_PARTIAL_SOFT is set, the
- return code PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL
- if the end of the subject is reached, there have been no complete
+ matches have already been found. When PCRE2_PARTIAL_SOFT is set, the
+ return code PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL
+ if the end of the subject is reached, there have been no complete
matches, but there is still at least one matching possibility. The por-
- tion of the string that was inspected when the longest partial match
+ tion of the string that was inspected when the longest partial match
was found is set as the first matching string in both cases. There is a
- more detailed discussion of partial and multi-segment matching, with
+ more detailed discussion of partial and multi-segment matching, with
examples, in the pcre2partial documentation.
PCRE2_DFA_SHORTEST
- Setting the PCRE2_DFA_SHORTEST option causes the matching algorithm to
+ Setting the PCRE2_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.
PCRE2_DFA_RESTART
- When pcre2_dfa_match() returns a partial match, it is possible to call
+ When pcre2_dfa_match() returns a partial match, it is possible to call
it again, with additional subject characters, and have it continue with
the same match. The PCRE2_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
+ 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
pcre2partial documentation.
@@ -2744,8 +2747,8 @@
When pcre2_dfa_match() 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
<.*>
@@ -2760,17 +2763,17 @@
<something> <something else>
<something>
- On success, the yield of the function is a number greater than zero,
- which is the number of matched substrings. The offsets of the sub-
- strings are returned in the ovector, and can be extracted by number in
- the same way as for pcre2_match(), but the numbers bear no relation to
- any capturing groups that may exist in the pattern, because DFA match-
+ On success, the yield of the function is a number greater than zero,
+ which is the number of matched substrings. The offsets of the sub-
+ strings are returned in the ovector, and can be extracted by number in
+ the same way as for pcre2_match(), but the numbers bear no relation to
+ any capturing groups that may exist in the pattern, because DFA match-
ing does not support group capture.
- Calls to the convenience functions that extract substrings by name
- return the error PCRE2_ERROR_DFA_UFUNC (unsupported function) if used
+ Calls to the convenience functions that extract substrings by name
+ return the error PCRE2_ERROR_DFA_UFUNC (unsupported function) if used
after a DFA match. The convenience functions that extract substrings by
- number never return PCRE2_ERROR_NOSUBSTRING, and the meanings of some
+ number never return PCRE2_ERROR_NOSUBSTRING, and the meanings of some
other errors are slightly different:
PCRE2_ERROR_UNAVAILABLE
@@ -2780,64 +2783,64 @@
PCRE2_ERROR_UNSET
- There is a slot in the ovector for this substring, but there were
+ There is a slot in the ovector for this substring, but there were
insufficient matches to fill it.
- The matched strings are stored in the ovector in reverse order of
- length; that is, the longest matching string is first. If there were
- too many matches to fit into the ovector, the yield of the function is
+ The matched strings are stored in the ovector in reverse order of
+ length; that is, the longest matching string is first. If there were
+ too many matches to fit into the ovector, the yield of the function is
zero, and the vector is filled with the longest matches.
- NOTE: PCRE2's "auto-possessification" optimization usually applies to
- character repeats at the end of a pattern (as well as internally). For
- example, the pattern "a\d+" is compiled as if it were "a\d++". For DFA
- matching, this means that only one possible match is found. If you
- really do want multiple matches in such cases, either use an ungreedy
- repeat auch as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when
+ NOTE: PCRE2's "auto-possessification" optimization usually applies to
+ character repeats at the end of a pattern (as well as internally). For
+ example, the pattern "a\d+" is compiled as if it were "a\d++". For DFA
+ matching, this means that only one possible match is found. If you
+ really do want multiple matches in such cases, either use an ungreedy
+ repeat auch as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when
compiling.
Error returns from pcre2_dfa_match()
The pcre2_dfa_match() function returns a negative number when it fails.
- Many of the errors are the same as for pcre2_match(), as described
+ Many of the errors are the same as for pcre2_match(), as described
above. There are in addition the following errors that are specific to
pcre2_dfa_match():
PCRE2_ERROR_DFA_UITEM
- This return is given if pcre2_dfa_match() encounters an item in the
+ This return is given if pcre2_dfa_match() encounters an item in the
pattern that it does not support, for instance, the use of \C or a back
reference.
PCRE2_ERROR_DFA_UCOND
- This return is given if pcre2_dfa_match() encounters a condition item
- that uses a back reference for the condition, or a test for recursion
+ This return is given if pcre2_dfa_match() 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.
PCRE2_ERROR_DFA_WSSIZE
- This return is given if pcre2_dfa_match() runs out of space in the
+ This return is given if pcre2_dfa_match() runs out of space in the
workspace vector.
PCRE2_ERROR_DFA_RECURSE
- When a recursive subpattern is processed, the matching function calls
+ When a recursive subpattern is processed, the matching function calls
itself recursively, using private memory for the ovector and workspace.
- This error is given if the internal ovector is not large enough. This
+ This error is given if the internal ovector is not large enough. This
should be extremely rare, as a vector of size 1000 is used.
PCRE2_ERROR_DFA_BADRESTART
- When pcre2_dfa_match() is called with the PCRE2_DFA_RESTART option,
- some plausibility checks are made on the contents of the workspace,
- which should contain data about the previous partial match. If any of
+ When pcre2_dfa_match() is called with the PCRE2_DFA_RESTART option,
+ some plausibility checks are made on the contents of the workspace,
+ which should contain data about the previous partial match. If any of
these checks fail, this error is given.
SEE ALSO
- pcre2build(3), pcre2callout(3), pcre2demo(3), pcre2matching(3),
+ pcre2build(3), pcre2callout(3), pcre2demo(3), pcre2matching(3),
pcre2partial(3), pcre2posix(3), pcre2sample(3), pcre2stack(3),
pcre2unicode(3).
@@ -2851,7 +2854,7 @@
REVISION
- Last updated: 30 August 2015
+ Last updated: 02 September 2015
Copyright (c) 1997-2015 University of Cambridge.
------------------------------------------------------------------------------
Modified: code/trunk/doc/pcre2test.txt
===================================================================
--- code/trunk/doc/pcre2test.txt 2015-09-12 18:10:57 UTC (rev 368)
+++ code/trunk/doc/pcre2test.txt 2015-09-12 18:12:01 UTC (rev 369)
@@ -247,6 +247,36 @@
as described in the section entitled "Saving and restoring compiled
patterns" below.
+ #newline_default [<newline-list>]
+
+ When PCRE2 is built, a default newline convention can be specified.
+ This determines which characters and/or character pairs are recognized
+ as indicating a newline in a pattern or subject string. The default can
+ be overridden when a pattern is compiled. The standard test files con-
+ tain tests of various newline conventions, but the majority of the
+ tests expect a single linefeed to be recognized as a newline by
+ default. Without special action the tests would fail when PCRE2 is com-
+ piled with either CR or CRLF as the default newline.
+
+ The #newline_default command specifies a list of newline types that are
+ acceptable as the default. The types must be one of CR, LF, CRLF, ANY-
+ CRLF, or ANY (in upper or lower case), for example:
+
+ #newline_default LF Any anyCRLF
+
+ If the default newline is in the list, this command has no effect. Oth-
+ erwise, except when testing the POSIX API, a newline modifier that
+ specifies the first newline convention in the list (LF in the above
+ example) is added to any pattern that does not already have a newline
+ modifier. If the newline list is empty, the feature is turned off. This
+ command is present in a number of the standard test input files.
+
+ When the POSIX API is being tested there is no way to override the
+ default newline convention, though it is possible to set the newline
+ convention from within the pattern. A warning is given if the posix
+ modifier is used when #newline_default would set a default for the non-
+ POSIX API.
+
#pattern <modifier-list>
This command sets a default modifier list that applies to all subse-
@@ -558,24 +588,50 @@
JIT compilation
- The /jit modifier may optionally be followed by an equals sign and a
- number in the range 0 to 7:
+ Just-in-time (JIT) compiling is a heavyweight optimization that can
+ greatly speed up pattern matching. See the pcre2jit documentation for
+ details. JIT compiling happens, optionally, after a pattern has been
+ successfully compiled into an internal form. The JIT compiler converts
+ this to optimized machine code. It needs to know whether the match-time
+ options PCRE2_PARTIAL_HARD and PCRE2_PARTIAL_SOFT are going to be used,
+ because different code is generated for the different cases. See the
+ partial modifier in "Subject Modifiers" below for details of how these
+ options are specified for each match attempt.
+ JIT compilation is requested by the /jit pattern modifier, which may
+ optionally be followed by an equals sign and a number in the range 0 to
+ 7. The three bits that make up the number specify which of the three
+ JIT operating modes are to be compiled:
+
+ 1 compile JIT code for non-partial matching
+ 2 compile JIT code for soft partial matching
+ 4 compile JIT code for hard partial matching
+
+ The possible values for the /jit modifier are therefore:
+
0 disable JIT
- 1 use JIT for normal match only
- 2 use JIT for soft partial match only
- 3 use JIT for normal match and soft partial match
- 4 use JIT for hard partial match only
- 6 use JIT for soft and hard partial match
+ 1 normal matching only
+ 2 soft partial matching only
+ 3 normal and soft partial matching
+ 4 hard partial matching only
+ 6 soft and hard partial matching only
7 all three modes
- If no number is given, 7 is assumed. If JIT compilation is successful,
- the compiled JIT code will automatically be used when pcre2_match() is
- run for the appropriate type of match, except when incompatible run-
- time options are specified. For more details, see the pcre2jit documen-
- tation. See also the jitstack modifier below for a way of setting the
- size of the JIT stack.
+ If no number is given, 7 is assumed. The phrase "partial matching"
+ means a call to pcre2_match() with either the PCRE2_PARTIAL_SOFT or the
+ PCRE2_PARTIAL_HARD option set. Note that such a call may return a com-
+ plete match; the options enable the possibility of a partial match, but
+ do not require it. Note also that if you request JIT compilation only
+ for partial matching (for example, /jit=2) but do not set the partial
+ modifier on a subject line, that match will not use JIT code because
+ none was compiled for non-partial matching.
+ If JIT compilation is successful, the compiled JIT code will automati-
+ cally be used when an appropriate type of match is run, except when
+ incompatible run-time options are specified. For more details, see the
+ pcre2jit documentation. See also the jitstack modifier below for a way
+ of setting the size of the JIT stack.
+
If the jitfast modifier is specified, matching is done using the JIT
"fast path" interface, pcre2_jit_match(), which skips some of the san-
ity checks that are done by pcre2_match(), and of course does not work
@@ -628,8 +684,10 @@
The /posix modifier causes pcre2test to call PCRE2 via the POSIX wrap-
per API rather than its native API. This supports only the 8-bit
- library. When the POSIX API is being used, the following pattern modi-
- fiers set options for the regcomp() function:
+ library. Note that it does not imply POSIX matching semantics; for
+ more detail see the pcre2posix documentation. When the POSIX API is
+ being used, the following pattern modifiers set options for the reg-
+ comp() function:
caseless REG_ICASE
multiline REG_NEWLINE
@@ -1333,5 +1391,5 @@
REVISION
- Last updated: 30 August 2015
+ Last updated: 12 September 2015
Copyright (c) 1997-2015 University of Cambridge.
