version 1.1.1.2, 2012/02/21 23:50:25
|
version 1.1.1.4, 2013/07/22 08:25:56
|
Line 1
|
Line 1
|
.TH PCREAPI 3 | .TH PCREAPI 3 "12 May 2013" "PCRE 8.33" |
.SH NAME |
.SH NAME |
PCRE - Perl-compatible regular expressions |
PCRE - Perl-compatible regular expressions |
.sp |
.sp |
Line 95 PCRE - Perl-compatible regular expressions
|
Line 95 PCRE - Perl-compatible regular expressions
|
.SH "PCRE NATIVE API AUXILIARY FUNCTIONS" |
.SH "PCRE NATIVE API AUXILIARY FUNCTIONS" |
.rs |
.rs |
.sp |
.sp |
|
.B int pcre_jit_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP," |
|
.ti +5n |
|
.B "const char *\fIsubject\fP," int \fIlength\fP, int \fIstartoffset\fP, |
|
.ti +5n |
|
.B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP, |
|
.ti +5n |
|
.B pcre_jit_stack *\fIjstack\fP); |
|
.PP |
.B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP); |
.B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP); |
.PP |
.PP |
.B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP); |
.B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP); |
Line 134 PCRE - Perl-compatible regular expressions
|
Line 142 PCRE - Perl-compatible regular expressions
|
.B int (*pcre_callout)(pcre_callout_block *); |
.B int (*pcre_callout)(pcre_callout_block *); |
. |
. |
. |
. |
.SH "PCRE 8-BIT AND 16-BIT LIBRARIES" | .SH "PCRE 8-BIT, 16-BIT, AND 32-BIT LIBRARIES" |
.rs |
.rs |
.sp |
.sp |
From release 8.30, PCRE can be compiled as a library for handling 16-bit | As well as support for 8-bit character strings, PCRE also supports 16-bit |
character strings as well as, or instead of, the original library that handles | strings (from release 8.30) and 32-bit strings (from release 8.32), by means of |
8-bit character strings. To avoid too much complication, this document | two additional libraries. They can be built as well as, or instead of, the |
describes the 8-bit versions of the functions, with only occasional references | 8-bit library. To avoid too much complication, this document describes the |
to the 16-bit library. | 8-bit versions of the functions, with only occasional references to the 16-bit |
| and 32-bit libraries. |
.P |
.P |
The 16-bit functions operate in the same way as their 8-bit counterparts; they | The 16-bit and 32-bit functions operate in the same way as their 8-bit |
just use different data types for their arguments and results, and their names | counterparts; they just use different data types for their arguments and |
start with \fBpcre16_\fP instead of \fBpcre_\fP. For every option that has UTF8 | results, and their names start with \fBpcre16_\fP or \fBpcre32_\fP instead of |
in its name (for example, PCRE_UTF8), there is a corresponding 16-bit name with | \fBpcre_\fP. For every option that has UTF8 in its name (for example, |
UTF8 replaced by UTF16. This facility is in fact just cosmetic; the 16-bit | PCRE_UTF8), there are corresponding 16-bit and 32-bit names with UTF8 replaced |
option names define the same bit values. | by UTF16 or UTF32, respectively. This facility is in fact just cosmetic; the |
| 16-bit and 32-bit option names define the same bit values. |
.P |
.P |
References to bytes and UTF-8 in this document should be read as references to |
References to bytes and UTF-8 in this document should be read as references to |
16-bit data quantities and UTF-16 when using the 16-bit library, unless | 16-bit data units and UTF-16 when using the 16-bit library, or 32-bit data |
specified otherwise. More details of the specific differences for the 16-bit | units and UTF-32 when using the 32-bit library, unless specified otherwise. |
library are given in the | More details of the specific differences for the 16-bit and 32-bit libraries |
| are given in the |
.\" HREF |
.\" HREF |
\fBpcre16\fP |
\fBpcre16\fP |
.\" |
.\" |
page. | and |
| .\" HREF |
| \fBpcre32\fP |
| .\" |
| pages. |
. |
. |
. |
. |
.SH "PCRE API OVERVIEW" |
.SH "PCRE API OVERVIEW" |
Line 213 used if available, by setting an option that is ignore
|
Line 228 used if available, by setting an option that is ignore
|
relevant. More complicated programs might need to make use of the functions |
relevant. More complicated programs might need to make use of the functions |
\fBpcre_jit_stack_alloc()\fP, \fBpcre_jit_stack_free()\fP, and |
\fBpcre_jit_stack_alloc()\fP, \fBpcre_jit_stack_free()\fP, and |
\fBpcre_assign_jit_stack()\fP in order to control the JIT code's memory usage. |
\fBpcre_assign_jit_stack()\fP in order to control the JIT code's memory usage. |
These functions are discussed in the | .P |
| From release 8.32 there is also a direct interface for JIT execution, which |
| gives improved performance. The JIT-specific functions are discussed in the |
.\" HREF |
.\" HREF |
\fBpcrejit\fP |
\fBpcrejit\fP |
.\" |
.\" |
Line 302 PCRE supports five different conventions for indicatin
|
Line 319 PCRE supports five different conventions for indicatin
|
strings: a single CR (carriage return) character, a single LF (linefeed) |
strings: a single CR (carriage return) character, a single LF (linefeed) |
character, the two-character sequence CRLF, any of the three preceding, or any |
character, the two-character sequence CRLF, any of the three preceding, or any |
Unicode newline sequence. The Unicode newline sequences are the three just |
Unicode newline sequence. The Unicode newline sequences are the three just |
mentioned, plus the single characters VT (vertical tab, U+000B), FF (formfeed, | mentioned, plus the single characters VT (vertical tab, U+000B), FF (form feed, |
U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS |
U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS |
(paragraph separator, U+2029). |
(paragraph separator, U+2029). |
.P |
.P |
Line 392 not recognized. The following information is available
|
Line 409 not recognized. The following information is available
|
PCRE_CONFIG_UTF8 |
PCRE_CONFIG_UTF8 |
.sp |
.sp |
The output is an integer that is set to one if UTF-8 support is available; |
The output is an integer that is set to one if UTF-8 support is available; |
otherwise it is set to zero. If this option is given to the 16-bit version of | otherwise it is set to zero. This value should normally be given to the 8-bit |
this function, \fBpcre16_config()\fP, the result is PCRE_ERROR_BADOPTION. | version of this function, \fBpcre_config()\fP. If it is given to the 16-bit |
| or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION. |
.sp |
.sp |
PCRE_CONFIG_UTF16 |
PCRE_CONFIG_UTF16 |
.sp |
.sp |
The output is an integer that is set to one if UTF-16 support is available; |
The output is an integer that is set to one if UTF-16 support is available; |
otherwise it is set to zero. This value should normally be given to the 16-bit |
otherwise it is set to zero. This value should normally be given to the 16-bit |
version of this function, \fBpcre16_config()\fP. If it is given to the 8-bit |
version of this function, \fBpcre16_config()\fP. If it is given to the 8-bit |
version of this function, the result is PCRE_ERROR_BADOPTION. | or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION. |
.sp |
.sp |
|
PCRE_CONFIG_UTF32 |
|
.sp |
|
The output is an integer that is set to one if UTF-32 support is available; |
|
otherwise it is set to zero. This value should normally be given to the 32-bit |
|
version of this function, \fBpcre32_config()\fP. If it is given to the 8-bit |
|
or 16-bit version of this function, the result is PCRE_ERROR_BADOPTION. |
|
.sp |
PCRE_CONFIG_UNICODE_PROPERTIES |
PCRE_CONFIG_UNICODE_PROPERTIES |
.sp |
.sp |
The output is an integer that is set to one if support for Unicode character |
The output is an integer that is set to one if support for Unicode character |
Line 422 unaligned)". If JIT support is not available, the resu
|
Line 447 unaligned)". If JIT support is not available, the resu
|
PCRE_CONFIG_NEWLINE |
PCRE_CONFIG_NEWLINE |
.sp |
.sp |
The output is an integer whose value specifies the default character sequence |
The output is an integer whose value specifies the default character sequence |
that is recognized as meaning "newline". The four values that are supported | that is recognized as meaning "newline". The values that are supported in |
are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for ANYCRLF, and -1 for ANY. | ASCII/Unicode environments are: 10 for LF, 13 for CR, 3338 for CRLF, -2 for |
Though they are derived from ASCII, the same values are returned in EBCDIC | ANYCRLF, and -1 for ANY. In EBCDIC environments, CR, ANYCRLF, and ANY yield the |
environments. The default should normally correspond to the standard sequence | same values. However, the value for LF is normally 21, though some EBCDIC |
for your operating system. | environments use 37. The corresponding values for CRLF are 3349 and 3365. The |
| default should normally correspond to the standard sequence for your operating |
| system. |
.sp |
.sp |
PCRE_CONFIG_BSR |
PCRE_CONFIG_BSR |
.sp |
.sp |
Line 440 or CRLF. The default can be overridden when a pattern
|
Line 467 or CRLF. The default can be overridden when a pattern
|
The output is an integer that contains the number of bytes used for internal |
The output is an integer that contains the number of bytes used for internal |
linkage in compiled regular expressions. For the 8-bit library, the value can |
linkage in compiled regular expressions. For the 8-bit library, the value can |
be 2, 3, or 4. For the 16-bit library, the value is either 2 or 4 and is still |
be 2, 3, or 4. For the 16-bit library, the value is either 2 or 4 and is still |
a number of bytes. The default value of 2 is sufficient for all but the most | a number of bytes. For the 32-bit library, the value is either 2 or 4 and is |
massive patterns, since it allows the compiled pattern to be up to 64K in size. | still a number of bytes. The default value of 2 is sufficient for all but the |
Larger values allow larger regular expressions to be compiled, at the expense | most massive patterns, since it allows the compiled pattern to be up to 64K in |
of slower matching. | size. Larger values allow larger regular expressions to be compiled, at the |
| expense of slower matching. |
.sp |
.sp |
PCRE_CONFIG_POSIX_MALLOC_THRESHOLD |
PCRE_CONFIG_POSIX_MALLOC_THRESHOLD |
.sp |
.sp |
Line 526 documentation). For those options that can be differen
|
Line 554 documentation). For those options that can be differen
|
the pattern, the contents of the \fIoptions\fP argument specifies their |
the pattern, the contents of the \fIoptions\fP argument specifies their |
settings at the start of compilation and execution. The PCRE_ANCHORED, |
settings at the start of compilation and execution. The PCRE_ANCHORED, |
PCRE_BSR_\fIxxx\fP, PCRE_NEWLINE_\fIxxx\fP, PCRE_NO_UTF8_CHECK, and |
PCRE_BSR_\fIxxx\fP, PCRE_NEWLINE_\fIxxx\fP, PCRE_NO_UTF8_CHECK, and |
PCRE_NO_START_OPT options can be set at the time of matching as well as at | PCRE_NO_START_OPTIMIZE options can be set at the time of matching as well as at |
compile time. |
compile time. |
.P |
.P |
If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately. |
If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately. |
Line 534 Otherwise, if compilation of a pattern fails, \fBpcre_
|
Line 562 Otherwise, if compilation of a pattern fails, \fBpcre_
|
NULL, and sets the variable pointed to by \fIerrptr\fP to point to a textual |
NULL, and sets the variable pointed to by \fIerrptr\fP to point to a textual |
error message. This is a static string that is part of the library. You must |
error message. This is a static string that is part of the library. You must |
not try to free it. Normally, the offset from the start of the pattern to the |
not try to free it. Normally, the offset from the start of the pattern to the |
byte that was being processed when the error was discovered is placed in the | data unit that was being processed when the error was discovered is placed in |
variable pointed to by \fIerroffset\fP, which must not be NULL (if it is, an | the variable pointed to by \fIerroffset\fP, which must not be NULL (if it is, |
immediate error is given). However, for an invalid UTF-8 string, the offset is | an immediate error is given). However, for an invalid UTF-8 or UTF-16 string, |
that of the first byte of the failing character. | the offset is that of the first data unit of the failing character. |
.P |
.P |
Some errors are not detected until the whole pattern has been scanned; in these |
Some errors are not detected until the whole pattern has been scanned; in these |
cases, the offset passed back is the length of the pattern. Note that the |
cases, the offset passed back is the length of the pattern. Note that the |
offset is in bytes, not characters, even in UTF-8 mode. It may sometimes point | offset is in data units, not characters, even in a UTF mode. It may sometimes |
into the middle of a UTF-8 character. | point into the middle of a UTF-8 or UTF-16 character. |
.P |
.P |
If \fBpcre_compile2()\fP is used instead of \fBpcre_compile()\fP, and the |
If \fBpcre_compile2()\fP is used instead of \fBpcre_compile()\fP, and the |
\fIerrorcodeptr\fP argument is not NULL, a non-zero error code number is |
\fIerrorcodeptr\fP argument is not NULL, a non-zero error code number is |
Line 642 documentation.
|
Line 670 documentation.
|
.sp |
.sp |
PCRE_EXTENDED |
PCRE_EXTENDED |
.sp |
.sp |
If this bit is set, whitespace data characters in the pattern are totally | If this bit is set, white space data characters in the pattern are totally |
ignored except when escaped or inside a character class. Whitespace does not | ignored except when escaped or inside a character class. White space does not |
include the VT character (code 11). In addition, characters between an |
include the VT character (code 11). In addition, characters between an |
unescaped # outside a character class and the next newline, inclusive, are also |
unescaped # outside a character class and the next newline, inclusive, are also |
ignored. This is equivalent to Perl's /x option, and it can be changed within a |
ignored. This is equivalent to Perl's /x option, and it can be changed within a |
Line 661 comment is a literal newline sequence in the pattern;
|
Line 689 comment is a literal newline sequence in the pattern;
|
happen to represent a newline do not count. |
happen to represent a newline do not count. |
.P |
.P |
This option makes it possible to include comments inside complicated patterns. |
This option makes it possible to include comments inside complicated patterns. |
Note, however, that this applies only to data characters. Whitespace characters | Note, however, that this applies only to data characters. White space characters |
may never appear within special character sequences in a pattern, for example |
may never appear within special character sequences in a pattern, for example |
within the sequence (?( that introduces a conditional subpattern. |
within the sequence (?( that introduces a conditional subpattern. |
.sp |
.sp |
Line 713 binary zero character followed by z).
|
Line 741 binary zero character followed by z).
|
.sp |
.sp |
PCRE_MULTILINE |
PCRE_MULTILINE |
.sp |
.sp |
By default, PCRE treats the subject string as consisting of a single line of | By default, for the purposes of matching "start of line" and "end of line", |
characters (even if it actually contains newlines). The "start of line" | PCRE treats the subject string as consisting of a single line of characters, |
metacharacter (^) matches only at the start of the string, while the "end of | even if it actually contains newlines. The "start of line" metacharacter (^) |
line" metacharacter ($) matches only at the end of the string, or before a | matches only at the start of the string, and the "end of line" metacharacter |
terminating newline (unless PCRE_DOLLAR_ENDONLY is set). This is the same as | ($) matches only at the end of the string, or before a terminating newline |
Perl. | (except when PCRE_DOLLAR_ENDONLY is set). Note, however, that unless |
| PCRE_DOTALL is set, the "any character" metacharacter (.) does not match at a |
| newline. This behaviour (for ^, $, and dot) is the same as Perl. |
.P |
.P |
When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs |
When PCRE_MULTILINE it is set, the "start of line" and "end of line" constructs |
match immediately following or immediately before internal newlines in the |
match immediately following or immediately before internal newlines in the |
Line 727 equivalent to Perl's /m option, and it can be changed
|
Line 757 equivalent to Perl's /m option, and it can be changed
|
(?m) option setting. If there are no newlines in a subject string, or no |
(?m) option setting. If there are no newlines in a subject string, or no |
occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no effect. |
occurrences of ^ or $ in a pattern, setting PCRE_MULTILINE has no effect. |
.sp |
.sp |
|
PCRE_NEVER_UTF |
|
.sp |
|
This option locks out interpretation of the pattern as UTF-8 (or UTF-16 or |
|
UTF-32 in the 16-bit and 32-bit libraries). In particular, it prevents the |
|
creator of the pattern from switching to UTF interpretation by starting the |
|
pattern with (*UTF). This may be useful in applications that process patterns |
|
from external sources. The combination of PCRE_UTF8 and PCRE_NEVER_UTF also |
|
causes an error. |
|
.sp |
PCRE_NEWLINE_CR |
PCRE_NEWLINE_CR |
PCRE_NEWLINE_LF |
PCRE_NEWLINE_LF |
PCRE_NEWLINE_CRLF |
PCRE_NEWLINE_CRLF |
Line 739 indicated by a single character (CR or LF, respectivel
|
Line 778 indicated by a single character (CR or LF, respectivel
|
PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character |
PCRE_NEWLINE_CRLF specifies that a newline is indicated by the two-character |
CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three |
CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three |
preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies |
preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies |
that any Unicode newline sequence should be recognized. The Unicode newline | that any Unicode newline sequence should be recognized. |
sequences are the three just mentioned, plus the single characters VT (vertical | |
tab, U+000B), FF (formfeed, U+000C), NEL (next line, U+0085), LS (line | |
separator, U+2028), and PS (paragraph separator, U+2029). For the 8-bit | |
library, the last two are recognized only in UTF-8 mode. | |
.P |
.P |
|
In an ASCII/Unicode environment, the Unicode newline sequences are the three |
|
just mentioned, plus the single characters VT (vertical tab, U+000B), FF (form |
|
feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS |
|
(paragraph separator, U+2029). For the 8-bit library, the last two are |
|
recognized only in UTF-8 mode. |
|
.P |
|
When PCRE is compiled to run in an EBCDIC (mainframe) environment, the code for |
|
CR is 0x0d, the same as ASCII. However, the character code for LF is normally |
|
0x15, though in some EBCDIC environments 0x25 is used. Whichever of these is |
|
not LF is made to correspond to Unicode's NEL character. EBCDIC codes are all |
|
less than 256. For more details, see the |
|
.\" HREF |
|
\fBpcrebuild\fP |
|
.\" |
|
documentation. |
|
.P |
The newline setting in the options word uses three bits that are treated |
The newline setting in the options word uses three bits that are treated |
as a number, giving eight possibilities. Currently only six are used (default |
as a number, giving eight possibilities. Currently only six are used (default |
plus the five values above). This means that if you set more than one newline |
plus the five values above). This means that if you set more than one newline |
Line 753 PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to
|
Line 804 PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is equivalent to
|
other combinations may yield unused numbers and cause an error. |
other combinations may yield unused numbers and cause an error. |
.P |
.P |
The only time that a line break in a pattern is specially recognized when |
The only time that a line break in a pattern is specially recognized when |
compiling is when PCRE_EXTENDED is set. CR and LF are whitespace characters, | compiling is when PCRE_EXTENDED is set. CR and LF are white space characters, |
and so are ignored in this mode. Also, an unescaped # outside a character class |
and so are ignored in this mode. Also, an unescaped # outside a character class |
indicates a comment that lasts until after the next line break sequence. In |
indicates a comment that lasts until after the next line break sequence. In |
other circumstances, line break sequences in patterns are treated as literal |
other circumstances, line break sequences in patterns are treated as literal |
Line 770 were followed by ?: but named parentheses can still be
|
Line 821 were followed by ?: but named parentheses can still be
|
they acquire numbers in the usual way). There is no equivalent of this option |
they acquire numbers in the usual way). There is no equivalent of this option |
in Perl. |
in Perl. |
.sp |
.sp |
NO_START_OPTIMIZE | PCRE_NO_START_OPTIMIZE |
.sp |
.sp |
This is an option that acts at matching time; that is, it is really an option |
This is an option that acts at matching time; that is, it is really an option |
for \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP. If it is set at compile time, |
for \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP. If it is set at compile time, |
it is remembered with the compiled pattern and assumed at matching time. For | it is remembered with the compiled pattern and assumed at matching time. This |
details see the discussion of PCRE_NO_START_OPTIMIZE | is necessary if you want to use JIT execution, because the JIT compiler needs |
| to know whether or not this option is set. For details see the discussion of |
| PCRE_NO_START_OPTIMIZE |
.\" HTML <a href="#execoptions"> |
.\" HTML <a href="#execoptions"> |
.\" </a> |
.\" </a> |
below. |
below. |
Line 819 page.
|
Line 872 page.
|
.sp |
.sp |
PCRE_NO_UTF8_CHECK |
PCRE_NO_UTF8_CHECK |
.sp |
.sp |
When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 | When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is |
string is automatically checked. There is a discussion about the | automatically checked. There is a discussion about the |
.\" HTML <a href="pcreunicode.html#utf8strings"> |
.\" HTML <a href="pcreunicode.html#utf8strings"> |
.\" </a> |
.\" </a> |
validity of UTF-8 strings |
validity of UTF-8 strings |
Line 835 this check for performance reasons, you can set the PC
|
Line 888 this check for performance reasons, you can set the PC
|
When it is set, the effect of passing an invalid UTF-8 string as a pattern is |
When it is set, the effect of passing an invalid UTF-8 string as a pattern is |
undefined. It may cause your program to crash. Note that this option can also |
undefined. It may cause your program to crash. Note that this option can also |
be passed to \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP, to suppress the |
be passed to \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP, to suppress the |
validity checking of subject strings. | validity checking of subject strings only. If the same string is being matched |
| many times, the option can be safely set for the second and subsequent |
| matchings to improve performance. |
. |
. |
. |
. |
.SH "COMPILATION ERROR CODES" |
.SH "COMPILATION ERROR CODES" |
Line 844 validity checking of subject strings.
|
Line 899 validity checking of subject strings.
|
The following table lists the error codes than may be returned by |
The following table lists the error codes than may be returned by |
\fBpcre_compile2()\fP, along with the error messages that may be returned by |
\fBpcre_compile2()\fP, along with the error messages that may be returned by |
both compiling functions. Note that error messages are always 8-bit ASCII |
both compiling functions. Note that error messages are always 8-bit ASCII |
strings, even in 16-bit mode. As PCRE has developed, some error codes have | strings, even in 16-bit or 32-bit mode. As PCRE has developed, some error codes |
fallen out of use. To avoid confusion, they have not been re-used. | have fallen out of use. To avoid confusion, they have not been re-used. |
.sp |
.sp |
0 no error |
0 no error |
1 \e at end of pattern |
1 \e at end of pattern |
Line 909 fallen out of use. To avoid confusion, they have not b
|
Line 964 fallen out of use. To avoid confusion, they have not b
|
name/number or by a plain number |
name/number or by a plain number |
58 a numbered reference must not be zero |
58 a numbered reference must not be zero |
59 an argument is not allowed for (*ACCEPT), (*FAIL), or (*COMMIT) |
59 an argument is not allowed for (*ACCEPT), (*FAIL), or (*COMMIT) |
60 (*VERB) not recognized | 60 (*VERB) not recognized or malformed |
61 number is too big |
61 number is too big |
62 subpattern name expected |
62 subpattern name expected |
63 digit expected after (?+ |
63 digit expected after (?+ |
Line 926 fallen out of use. To avoid confusion, they have not b
|
Line 981 fallen out of use. To avoid confusion, they have not b
|
72 too many forward references |
72 too many forward references |
73 disallowed Unicode code point (>= 0xd800 && <= 0xdfff) |
73 disallowed Unicode code point (>= 0xd800 && <= 0xdfff) |
74 invalid UTF-16 string (specifically UTF-16) |
74 invalid UTF-16 string (specifically UTF-16) |
|
75 name is too long in (*MARK), (*PRUNE), (*SKIP), or (*THEN) |
|
76 character value in \eu.... sequence is too large |
|
77 invalid UTF-32 string (specifically UTF-32) |
.sp |
.sp |
The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may |
The numbers 32 and 10000 in errors 48 and 49 are defaults; different values may |
be used if the limits were changed when PCRE was built. |
be used if the limits were changed when PCRE was built. |
Line 958 below
|
Line 1016 below
|
in the section on matching a pattern. |
in the section on matching a pattern. |
.P |
.P |
If studying the pattern does not produce any useful information, |
If studying the pattern does not produce any useful information, |
\fBpcre_study()\fP returns NULL. In that circumstance, if the calling program | \fBpcre_study()\fP returns NULL by default. In that circumstance, if the |
wants to pass any of the other fields to \fBpcre_exec()\fP or | calling program wants to pass any of the other fields to \fBpcre_exec()\fP or |
\fBpcre_dfa_exec()\fP, it must set up its own \fBpcre_extra\fP block. | \fBpcre_dfa_exec()\fP, it must set up its own \fBpcre_extra\fP block. However, |
| if \fBpcre_study()\fP is called with the PCRE_STUDY_EXTRA_NEEDED option, it |
| returns a \fBpcre_extra\fP block even if studying did not find any additional |
| information. It may still return NULL, however, if an error occurs in |
| \fBpcre_study()\fP. |
.P |
.P |
The second argument of \fBpcre_study()\fP contains option bits. There is only | The second argument of \fBpcre_study()\fP contains option bits. There are three |
one option: PCRE_STUDY_JIT_COMPILE. If this is set, and the just-in-time | further options in addition to PCRE_STUDY_EXTRA_NEEDED: |
compiler is available, the pattern is further compiled into machine code that | .sp |
executes much faster than the \fBpcre_exec()\fP matching function. If | PCRE_STUDY_JIT_COMPILE |
the just-in-time compiler is not available, this option is ignored. All other | PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE |
bits in the \fIoptions\fP argument must be zero. | PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE |
| .sp |
| If any of these are set, and the just-in-time compiler is available, the |
| pattern is further compiled into machine code that executes much faster than |
| the \fBpcre_exec()\fP interpretive matching function. If the just-in-time |
| compiler is not available, these options are ignored. All undefined bits in the |
| \fIoptions\fP argument must be zero. |
.P |
.P |
JIT compilation is a heavyweight optimization. It can take some time for |
JIT compilation is a heavyweight optimization. It can take some time for |
patterns to be analyzed, and for one-off matches and simple patterns the |
patterns to be analyzed, and for one-off matches and simple patterns the |
Line 991 When you are finished with a pattern, you can free the
|
Line 1059 When you are finished with a pattern, you can free the
|
study data by calling \fBpcre_free_study()\fP. This function was added to the |
study data by calling \fBpcre_free_study()\fP. This function was added to the |
API for release 8.20. For earlier versions, the memory could be freed with |
API for release 8.20. For earlier versions, the memory could be freed with |
\fBpcre_free()\fP, just like the pattern itself. This will still work in cases |
\fBpcre_free()\fP, just like the pattern itself. This will still work in cases |
where PCRE_STUDY_JIT_COMPILE is not used, but it is advisable to change to the | where JIT optimization is not used, but it is advisable to change to the new |
new function when convenient. | function when convenient. |
.P |
.P |
This is a typical way in which \fBpcre_study\fP() is used (except that in a |
This is a typical way in which \fBpcre_study\fP() is used (except that in a |
real application there should be tests for errors): |
real application there should be tests for errors): |
Line 1014 real application there should be tests for errors):
|
Line 1082 real application there should be tests for errors):
|
Studying a pattern does two things: first, a lower bound for the length of |
Studying a pattern does two things: first, a lower bound for the length of |
subject string that is needed to match the pattern is computed. This does not |
subject string that is needed to match the pattern is computed. This does not |
mean that there are any strings of that length that match, but it does |
mean that there are any strings of that length that match, but it does |
guarantee that no shorter strings match. The value is used by | guarantee that no shorter strings match. The value is used to avoid wasting |
\fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP to avoid wasting time by trying to | time by trying to match strings that are shorter than the lower bound. You can |
match strings that are shorter than the lower bound. You can find out the value | find out the value in a calling program via the \fBpcre_fullinfo()\fP function. |
in a calling program via the \fBpcre_fullinfo()\fP function. | |
.P |
.P |
Studying a pattern is also useful for non-anchored patterns that do not have a |
Studying a pattern is also useful for non-anchored patterns that do not have a |
single fixed starting character. A bitmap of possible starting bytes is |
single fixed starting character. A bitmap of possible starting bytes is |
created. This speeds up finding a position in the subject at which to start |
created. This speeds up finding a position in the subject at which to start |
matching. (In 16-bit mode, the bitmap is used for 16-bit values less than 256.) | matching. (In 16-bit mode, the bitmap is used for 16-bit values less than 256. |
| In 32-bit mode, the bitmap is used for 32-bit values less than 256.) |
.P |
.P |
These two optimizations apply to both \fBpcre_exec()\fP and |
These two optimizations apply to both \fBpcre_exec()\fP and |
\fBpcre_dfa_exec()\fP. However, they are not used by \fBpcre_exec()\fP if | \fBpcre_dfa_exec()\fP, and the information is also used by the JIT compiler. |
\fBpcre_study()\fP is called with the PCRE_STUDY_JIT_COMPILE option, and | The optimizations can be disabled by setting the PCRE_NO_START_OPTIMIZE option. |
just-in-time compiling is successful. The optimizations can be disabled by | You might want to do this if your pattern contains callouts or (*MARK) and you |
setting the PCRE_NO_START_OPTIMIZE option when calling \fBpcre_exec()\fP or | want to make use of these facilities in cases where matching fails. |
\fBpcre_dfa_exec()\fP. You might want to do this if your pattern contains | .P |
callouts or (*MARK) (which cannot be handled by the JIT compiler), and you want | PCRE_NO_START_OPTIMIZE can be specified at either compile time or execution |
to make use of these facilities in cases where matching fails. See the | time. However, if PCRE_NO_START_OPTIMIZE is passed to \fBpcre_exec()\fP, (that |
discussion of PCRE_NO_START_OPTIMIZE | is, after any JIT compilation has happened) JIT execution is disabled. For JIT |
| execution to work with PCRE_NO_START_OPTIMIZE, the option must be set at |
| compile time. |
| .P |
| There is a longer discussion of PCRE_NO_START_OPTIMIZE |
.\" HTML <a href="#execoptions"> |
.\" HTML <a href="#execoptions"> |
.\" </a> |
.\" </a> |
below. |
below. |
Line 1123 the following negative numbers:
|
Line 1195 the following negative numbers:
|
PCRE_ERROR_BADENDIANNESS the pattern was compiled with different |
PCRE_ERROR_BADENDIANNESS the pattern was compiled with different |
endianness |
endianness |
PCRE_ERROR_BADOPTION the value of \fIwhat\fP was invalid |
PCRE_ERROR_BADOPTION the value of \fIwhat\fP was invalid |
|
PCRE_ERROR_UNSET the requested field is not set |
.sp |
.sp |
The "magic number" is placed at the start of each compiled pattern as an simple |
The "magic number" is placed at the start of each compiled pattern as an simple |
check against passing an arbitrary memory pointer. The endianness error can |
check against passing an arbitrary memory pointer. The endianness error can |
Line 1169 variable.
|
Line 1242 variable.
|
.P |
.P |
If there is a fixed first value, for example, the letter "c" from a pattern |
If there is a fixed first value, for example, the letter "c" from a pattern |
such as (cat|cow|coyote), its value is returned. In the 8-bit library, the |
such as (cat|cow|coyote), its value is returned. In the 8-bit library, the |
value is always less than 256; in the 16-bit library the value can be up to | value is always less than 256. In the 16-bit library the value can be up to |
0xffff. | 0xffff. In the 32-bit library the value can be up to 0x10ffff. |
.P |
.P |
If there is no fixed first value, and if either |
If there is no fixed first value, and if either |
.sp |
.sp |
Line 1183 starts with "^", or
|
Line 1256 starts with "^", or
|
-1 is returned, indicating that the pattern matches only at the start of a |
-1 is returned, indicating that the pattern matches only at the start of a |
subject string or after any newline within the string. Otherwise -2 is |
subject string or after any newline within the string. Otherwise -2 is |
returned. For anchored patterns, -2 is returned. |
returned. For anchored patterns, -2 is returned. |
|
.P |
|
Since for the 32-bit library using the non-UTF-32 mode, this function is unable |
|
to return the full 32-bit range of the character, this value is deprecated; |
|
instead the PCRE_INFO_FIRSTCHARACTERFLAGS and PCRE_INFO_FIRSTCHARACTER values |
|
should be used. |
.sp |
.sp |
PCRE_INFO_FIRSTTABLE |
PCRE_INFO_FIRSTTABLE |
.sp |
.sp |
Line 1205 Return 1 if the (?J) or (?-J) option setting is used i
|
Line 1283 Return 1 if the (?J) or (?-J) option setting is used i
|
.sp |
.sp |
PCRE_INFO_JIT |
PCRE_INFO_JIT |
.sp |
.sp |
Return 1 if the pattern was studied with the PCRE_STUDY_JIT_COMPILE option, and | Return 1 if the pattern was studied with one of the JIT options, and |
just-in-time compiling was successful. The fourth argument should point to an |
just-in-time compiling was successful. The fourth argument should point to an |
\fBint\fP variable. A return value of 0 means that JIT support is not available |
\fBint\fP variable. A return value of 0 means that JIT support is not available |
in this version of PCRE, or that the pattern was not studied with the | in this version of PCRE, or that the pattern was not studied with a JIT option, |
PCRE_STUDY_JIT_COMPILE option, or that the JIT compiler could not handle this | or that the JIT compiler could not handle this particular pattern. See the |
particular pattern. See the | |
.\" HREF |
.\" HREF |
\fBpcrejit\fP |
\fBpcrejit\fP |
.\" |
.\" |
Line 1218 documentation for details of what can and cannot be ha
|
Line 1295 documentation for details of what can and cannot be ha
|
.sp |
.sp |
PCRE_INFO_JITSIZE |
PCRE_INFO_JITSIZE |
.sp |
.sp |
If the pattern was successfully studied with the PCRE_STUDY_JIT_COMPILE option, | If the pattern was successfully studied with a JIT option, return the size of |
return the size of the JIT compiled code, otherwise return zero. The fourth | the JIT compiled code, otherwise return zero. The fourth argument should point |
argument should point to a \fBsize_t\fP variable. | to a \fBsize_t\fP variable. |
.sp |
.sp |
PCRE_INFO_LASTLITERAL |
PCRE_INFO_LASTLITERAL |
.sp |
.sp |
Line 1231 value, -1 is returned. For anchored patterns, a last l
|
Line 1308 value, -1 is returned. For anchored patterns, a last l
|
only if it follows something of variable length. For example, for the pattern |
only if it follows something of variable length. For example, for the pattern |
/^a\ed+z\ed+/ the returned value is "z", but for /^a\edz\ed/ the returned value |
/^a\ed+z\ed+/ the returned value is "z", but for /^a\edz\ed/ the returned value |
is -1. |
is -1. |
|
.P |
|
Since for the 32-bit library using the non-UTF-32 mode, this function is unable |
|
to return the full 32-bit range of the character, this value is deprecated; |
|
instead the PCRE_INFO_REQUIREDCHARFLAGS and PCRE_INFO_REQUIREDCHAR values should |
|
be used. |
.sp |
.sp |
|
PCRE_INFO_MATCHLIMIT |
|
.sp |
|
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 fourth argument |
|
should point to an unsigned 32-bit integer. If no such value has been set, the |
|
call to \fBpcre_fullinfo()\fP returns the error PCRE_ERROR_UNSET. |
|
.sp |
|
PCRE_INFO_MAXLOOKBEHIND |
|
.sp |
|
Return the number of characters (NB not data units) in the longest lookbehind |
|
assertion in the pattern. This information is useful when doing multi-segment |
|
matching using the partial matching facilities. Note that the simple assertions |
|
\eb and \eB require a one-character lookbehind. \eA 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 processed. Otherwise, if there are no |
|
lookbehinds in the pattern, \eA might match incorrectly at the start of a new |
|
segment. |
|
.sp |
PCRE_INFO_MINLENGTH |
PCRE_INFO_MINLENGTH |
.sp |
.sp |
If the pattern was studied and a minimum length for matching subject strings |
If the pattern was studied and a minimum length for matching subject strings |
was computed, its value is returned. Otherwise the returned value is -1. The |
was computed, its value is returned. Otherwise the returned value is -1. The |
value is a number of characters, which in UTF-8 mode may be different from the | value is a number of characters, which in UTF mode may be different from the |
number of bytes. The fourth argument should point to an \fBint\fP variable. A | number of data units. The fourth argument should point to an \fBint\fP |
non-negative value is a lower bound to the length of any matching string. There | variable. A non-negative value is a lower bound to the length of any matching |
may not be any strings of that length that do actually match, but every string | string. There may not be any strings of that length that do actually match, but |
that does match is at least that long. | every string that does match is at least that long. |
.sp |
.sp |
PCRE_INFO_NAMECOUNT |
PCRE_INFO_NAMECOUNT |
PCRE_INFO_NAMEENTRYSIZE |
PCRE_INFO_NAMEENTRYSIZE |
Line 1263 length of the longest name. PCRE_INFO_NAMETABLE return
|
Line 1364 length of the longest name. PCRE_INFO_NAMETABLE return
|
entry of the table. This is a pointer to \fBchar\fP in the 8-bit library, where |
entry of the table. This is a pointer to \fBchar\fP in the 8-bit library, where |
the first two bytes of each entry are the number of the capturing parenthesis, |
the first two bytes of each entry are the number of the capturing parenthesis, |
most significant byte first. In the 16-bit library, the pointer points to |
most significant byte first. In the 16-bit library, the pointer points to |
16-bit data units, the first of which contains the parenthesis number. The rest | 16-bit data units, the first of which contains the parenthesis number. In the |
of the entry is the corresponding name, zero terminated. | 32-bit library, the pointer points to 32-bit data units, the first of which |
| contains the parenthesis number. The rest of the entry is the corresponding |
| name, zero terminated. |
.P |
.P |
The names are in alphabetical order. Duplicate names may appear if (?| is used |
The names are in alphabetical order. Duplicate names may appear if (?| is used |
to create multiple groups with the same number, as described in the |
to create multiple groups with the same number, as described in the |
Line 1337 alternatives begin with one of the following:
|
Line 1440 alternatives begin with one of the following:
|
For such patterns, the PCRE_ANCHORED bit is set in the options returned by |
For such patterns, the PCRE_ANCHORED bit is set in the options returned by |
\fBpcre_fullinfo()\fP. |
\fBpcre_fullinfo()\fP. |
.sp |
.sp |
|
PCRE_INFO_RECURSIONLIMIT |
|
.sp |
|
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 fourth |
|
argument should point to an unsigned 32-bit integer. If no such value has been |
|
set, the call to \fBpcre_fullinfo()\fP returns the error PCRE_ERROR_UNSET. |
|
.sp |
PCRE_INFO_SIZE |
PCRE_INFO_SIZE |
.sp |
.sp |
Return the size of the compiled pattern in bytes (for both libraries). The | Return the size of the compiled pattern in bytes (for all three libraries). The |
fourth argument should point to a \fBsize_t\fP variable. This value does not |
fourth argument should point to a \fBsize_t\fP variable. This value does not |
include the size of the \fBpcre\fP structure that is returned by |
include the size of the \fBpcre\fP structure that is returned by |
\fBpcre_compile()\fP. The value that is passed as the argument to |
\fBpcre_compile()\fP. The value that is passed as the argument to |
Line 1350 does not alter the value returned by this option.
|
Line 1460 does not alter the value returned by this option.
|
.sp |
.sp |
PCRE_INFO_STUDYSIZE |
PCRE_INFO_STUDYSIZE |
.sp |
.sp |
Return the size in bytes of the data block pointed to by the \fIstudy_data\fP | Return the size in bytes (for all three libraries) of the data block pointed to |
field in a \fBpcre_extra\fP block. If \fBpcre_extra\fP is NULL, or there is no | by the \fIstudy_data\fP field in a \fBpcre_extra\fP block. If \fBpcre_extra\fP |
study data, zero is returned. The fourth argument should point to a | is NULL, or there is no study data, zero is returned. The fourth argument |
\fBsize_t\fP variable. The \fIstudy_data\fP field is set by \fBpcre_study()\fP | should point to a \fBsize_t\fP variable. The \fIstudy_data\fP field is set by |
to record information that will speed up matching (see the section entitled | \fBpcre_study()\fP to record information that will speed up matching (see the |
| section entitled |
.\" HTML <a href="#studyingapattern"> |
.\" HTML <a href="#studyingapattern"> |
.\" </a> |
.\" </a> |
"Studying a pattern" |
"Studying a pattern" |
Line 1365 is made available via this option so that it can be sa
|
Line 1476 is made available via this option so that it can be sa
|
\fBpcreprecompile\fP |
\fBpcreprecompile\fP |
.\" |
.\" |
documentation for details). |
documentation for details). |
|
.sp |
|
PCRE_INFO_FIRSTCHARACTERFLAGS |
|
.sp |
|
Return information about the first data unit of any matched string, for a |
|
non-anchored pattern. The fourth argument should point to an \fBint\fP |
|
variable. |
|
.P |
|
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 PCRE_INFO_FIRSTCHARACTER. |
|
.P |
|
If there is no fixed first value, and if either |
|
.sp |
|
(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch |
|
starts with "^", or |
|
.sp |
|
(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set |
|
(if it were set, the pattern would be anchored), |
|
.sp |
|
2 is returned, indicating that the pattern matches only at the start of a |
|
subject string or after any newline within the string. Otherwise 0 is |
|
returned. For anchored patterns, 0 is returned. |
|
.sp |
|
PCRE_INFO_FIRSTCHARACTER |
|
.sp |
|
Return the fixed first character value, if PCRE_INFO_FIRSTCHARACTERFLAGS |
|
returned 1; otherwise returns 0. The fourth argument should point to an |
|
\fBuint_t\fP variable. |
|
.P |
|
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. |
|
.P |
|
If there is no fixed first value, and if either |
|
.sp |
|
(a) the pattern was compiled with the PCRE_MULTILINE option, and every branch |
|
starts with "^", or |
|
.sp |
|
(b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set |
|
(if it were set, the pattern would be anchored), |
|
.sp |
|
-1 is returned, indicating that the pattern matches only at the start of a |
|
subject string or after any newline within the string. Otherwise -2 is |
|
returned. For anchored patterns, -2 is returned. |
|
.sp |
|
PCRE_INFO_REQUIREDCHARFLAGS |
|
.sp |
|
Returns 1 if there is a rightmost literal data unit that must exist in any |
|
matched string, other than at its start. The fourth argument should point to |
|
an \fBint\fP variable. If there is no such value, 0 is returned. If returning |
|
1, the character value itself can be retrieved using PCRE_INFO_REQUIREDCHAR. |
|
.P |
|
For anchored patterns, a last literal value is recorded only if it follows |
|
something of variable length. For example, for the pattern /^a\ed+z\ed+/ the |
|
returned value 1 (with "z" returned from PCRE_INFO_REQUIREDCHAR), but for |
|
/^a\edz\ed/ the returned value is 0. |
|
.sp |
|
PCRE_INFO_REQUIREDCHAR |
|
.sp |
|
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 |
|
fourth argument should point to an \fBuint32_t\fP variable. If there is no such |
|
value, 0 is returned. |
. |
. |
. |
. |
.SH "REFERENCE COUNTS" |
.SH "REFERENCE COUNTS" |
Line 1461 fields (not necessarily in this order):
|
Line 1635 fields (not necessarily in this order):
|
.sp |
.sp |
In the 16-bit version of this structure, the \fImark\fP field has type |
In the 16-bit version of this structure, the \fImark\fP field has type |
"PCRE_UCHAR16 **". |
"PCRE_UCHAR16 **". |
|
.sp |
|
In the 32-bit version of this structure, the \fImark\fP field has type |
|
"PCRE_UCHAR32 **". |
.P |
.P |
The \fIflags\fP field is a bitmap that specifies which of the other fields | The \fIflags\fP field is used to specify which of the other fields are set. The |
are set. The flag bits are: | flag bits are: |
.sp |
.sp |
PCRE_EXTRA_STUDY_DATA | PCRE_EXTRA_CALLOUT_DATA |
PCRE_EXTRA_EXECUTABLE_JIT |
PCRE_EXTRA_EXECUTABLE_JIT |
|
PCRE_EXTRA_MARK |
PCRE_EXTRA_MATCH_LIMIT |
PCRE_EXTRA_MATCH_LIMIT |
PCRE_EXTRA_MATCH_LIMIT_RECURSION |
PCRE_EXTRA_MATCH_LIMIT_RECURSION |
PCRE_EXTRA_CALLOUT_DATA | PCRE_EXTRA_STUDY_DATA |
PCRE_EXTRA_TABLES |
PCRE_EXTRA_TABLES |
PCRE_EXTRA_MARK |
|
.sp |
.sp |
Other flag bits should be set to zero. The \fIstudy_data\fP field and sometimes |
Other flag bits should be set to zero. The \fIstudy_data\fP field and sometimes |
the \fIexecutable_jit\fP field are set in the \fBpcre_extra\fP block that is |
the \fIexecutable_jit\fP field are set in the \fBpcre_extra\fP block that is |
returned by \fBpcre_study()\fP, together with the appropriate flag bits. You |
returned by \fBpcre_study()\fP, together with the appropriate flag bits. You |
should not set these yourself, but you may add to the block by setting the | should not set these yourself, but you may add to the block by setting other |
other fields and their corresponding flag bits. | fields and their corresponding flag bits. |
.P |
.P |
The \fImatch_limit\fP field provides a means of preventing PCRE from using up a |
The \fImatch_limit\fP field provides a means of preventing PCRE from using up a |
vast amount of resources when running patterns that are not going to match, |
vast amount of resources when running patterns that are not going to match, |
Line 1492 patterns that are not anchored, the count restarts fro
|
Line 1669 patterns that are not anchored, the count restarts fro
|
in the subject string. |
in the subject string. |
.P |
.P |
When \fBpcre_exec()\fP is called with a pattern that was successfully studied |
When \fBpcre_exec()\fP is called with a pattern that was successfully studied |
with the PCRE_STUDY_JIT_COMPILE option, the way that the matching is executed | with a JIT option, the way that the matching is executed is entirely different. |
is entirely different. However, there is still the possibility of runaway | However, there is still the possibility of runaway matching that goes on for a |
matching that goes on for a very long time, and so the \fImatch_limit\fP value | very long time, and so the \fImatch_limit\fP value is also used in this case |
is also used in this case (but in a different way) to limit how long the | (but in a different way) to limit how long the matching can continue. |
matching can continue. | |
.P |
.P |
The default value for the limit can be set when PCRE is built; the default |
The default value for the limit can be set when PCRE is built; the default |
default is 10 million, which handles all but the most extreme cases. You can |
default is 10 million, which handles all but the most extreme cases. You can |
Line 1505 block in which \fImatch_limit\fP is set, and PCRE_EXTR
|
Line 1681 block in which \fImatch_limit\fP is set, and PCRE_EXTR
|
the \fIflags\fP field. If the limit is exceeded, \fBpcre_exec()\fP returns |
the \fIflags\fP field. If the limit is exceeded, \fBpcre_exec()\fP returns |
PCRE_ERROR_MATCHLIMIT. |
PCRE_ERROR_MATCHLIMIT. |
.P |
.P |
|
A value for the match limit may also be supplied by an item at the start of a |
|
pattern of the form |
|
.sp |
|
(*LIMIT_MATCH=d) |
|
.sp |
|
where d is a decimal number. However, such a setting is ignored unless d is |
|
less than the limit set by the caller of \fBpcre_exec()\fP or, if no such limit |
|
is set, less than the default. |
|
.P |
The \fImatch_limit_recursion\fP field is similar to \fImatch_limit\fP, but |
The \fImatch_limit_recursion\fP field is similar to \fImatch_limit\fP, but |
instead of limiting the total number of times that \fBmatch()\fP is called, it |
instead of limiting the total number of times that \fBmatch()\fP is called, it |
limits the depth of recursion. The recursion depth is a smaller number than the |
limits the depth of recursion. The recursion depth is a smaller number than the |
Line 1514 This limit is of use only if it is set smaller than \f
|
Line 1699 This limit is of use only if it is set smaller than \f
|
Limiting the recursion depth limits the amount of machine stack that can be |
Limiting the recursion depth limits the amount of machine stack that can be |
used, or, when PCRE has been compiled to use memory on the heap instead of the |
used, or, when PCRE has been compiled to use memory on the heap instead of the |
stack, the amount of heap memory that can be used. This limit is not relevant, |
stack, the amount of heap memory that can be used. This limit is not relevant, |
and is ignored, if the pattern was successfully studied with | and is ignored, when matching is done using JIT compiled code. |
PCRE_STUDY_JIT_COMPILE. | |
.P |
.P |
The default value for \fImatch_limit_recursion\fP can be set when PCRE is |
The default value for \fImatch_limit_recursion\fP can be set when PCRE is |
built; the default default is the same value as the default for |
built; the default default is the same value as the default for |
Line 1524 with a \fBpcre_extra\fP block in which \fImatch_limit_
|
Line 1708 with a \fBpcre_extra\fP block in which \fImatch_limit_
|
PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the \fIflags\fP field. If the limit |
PCRE_EXTRA_MATCH_LIMIT_RECURSION is set in the \fIflags\fP field. If the limit |
is exceeded, \fBpcre_exec()\fP returns PCRE_ERROR_RECURSIONLIMIT. |
is exceeded, \fBpcre_exec()\fP returns PCRE_ERROR_RECURSIONLIMIT. |
.P |
.P |
|
A value for the recursion limit may also be supplied by an item at the start of |
|
a pattern of the form |
|
.sp |
|
(*LIMIT_RECURSION=d) |
|
.sp |
|
where d is a decimal number. However, such a setting is ignored unless d is |
|
less than the limit set by the caller of \fBpcre_exec()\fP or, if no such limit |
|
is set, less than the default. |
|
.P |
The \fIcallout_data\fP field is used in conjunction with the "callout" feature, |
The \fIcallout_data\fP field is used in conjunction with the "callout" feature, |
and is described in the |
and is described in the |
.\" HREF |
.\" HREF |
Line 1572 documentation.
|
Line 1765 documentation.
|
The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be |
The unused bits of the \fIoptions\fP argument for \fBpcre_exec()\fP must be |
zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP, |
zero. The only bits that may be set are PCRE_ANCHORED, PCRE_NEWLINE_\fIxxx\fP, |
PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART, |
PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART, |
PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and | PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_HARD, and |
PCRE_PARTIAL_HARD. | PCRE_PARTIAL_SOFT. |
.P |
.P |
If the pattern was successfully studied with the PCRE_STUDY_JIT_COMPILE option, | If the pattern was successfully studied with one of the just-in-time (JIT) |
the only supported options for JIT execution are PCRE_NO_UTF8_CHECK, | compile options, the only supported options for JIT execution are |
PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, and PCRE_NOTEMPTY_ATSTART. Note in | PCRE_NO_UTF8_CHECK, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, |
particular that partial matching is not supported. If an unsupported option is | PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and PCRE_PARTIAL_SOFT. If an |
used, JIT execution is disabled and the normal interpretive code in | unsupported option is used, JIT execution is disabled and the normal |
\fBpcre_exec()\fP is run. | interpretive code in \fBpcre_exec()\fP is run. |
.sp |
.sp |
PCRE_ANCHORED |
PCRE_ANCHORED |
.sp |
.sp |
Line 1689 unanchored match must start with a specific character,
|
Line 1882 unanchored match must start with a specific character,
|
for that character, and fails immediately if it cannot find it, without |
for that character, and fails immediately if it cannot find it, without |
actually running the main matching function. This means that a special item |
actually running the main matching function. This means that a special item |
such as (*COMMIT) at the start of a pattern is not considered until after a |
such as (*COMMIT) at the start of a pattern is not considered until after a |
suitable starting point for the match has been found. When callouts or (*MARK) | suitable starting point for the match has been found. Also, when callouts or |
items are in use, these "start-up" optimizations can cause them to be skipped | (*MARK) items are in use, these "start-up" optimizations can cause them to be |
if the pattern is never actually used. The start-up optimizations are in effect | skipped if the pattern is never actually used. The start-up optimizations are |
a pre-scan of the subject that takes place before the pattern is run. | in effect a pre-scan of the subject that takes place before the pattern is run. |
.P |
.P |
The PCRE_NO_START_OPTIMIZE option disables the start-up optimizations, possibly |
The PCRE_NO_START_OPTIMIZE option disables the start-up optimizations, possibly |
causing performance to suffer, but ensuring that in cases where the result is |
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) |
"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. If |
are considered at every possible starting position in the subject string. If |
PCRE_NO_START_OPTIMIZE is set at compile time, it cannot be unset at matching |
PCRE_NO_START_OPTIMIZE is set at compile time, it cannot be unset at matching |
time. | time. The use of PCRE_NO_START_OPTIMIZE at matching time (that is, passing it |
| to \fBpcre_exec()\fP) disables JIT execution; in this situation, matching is |
| always done using interpretively. |
.P |
.P |
Setting PCRE_NO_START_OPTIMIZE can change the outcome of a matching operation. |
Setting PCRE_NO_START_OPTIMIZE can change the outcome of a matching operation. |
Consider the pattern |
Consider the pattern |
Line 1732 returned.
|
Line 1927 returned.
|
.sp |
.sp |
When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8 |
When PCRE_UTF8 is set at compile time, the validity of the subject as a UTF-8 |
string is automatically checked when \fBpcre_exec()\fP is subsequently called. |
string is automatically checked when \fBpcre_exec()\fP is subsequently called. |
The value of \fIstartoffset\fP is also checked to ensure that it points to the | The entire string is checked before any other processing takes place. The value |
start of a UTF-8 character. There is a discussion about the validity of UTF-8 | of \fIstartoffset\fP is also checked to ensure that it points to the start of a |
strings in the | UTF-8 character. There is a discussion about the |
| .\" HTML <a href="pcreunicode.html#utf8strings"> |
| .\" </a> |
| validity of UTF-8 strings |
| .\" |
| in the |
.\" HREF |
.\" HREF |
\fBpcreunicode\fP |
\fBpcreunicode\fP |
.\" |
.\" |
Line 1794 documentation.
|
Line 1994 documentation.
|
.rs |
.rs |
.sp |
.sp |
The subject string is passed to \fBpcre_exec()\fP as a pointer in |
The subject string is passed to \fBpcre_exec()\fP as a pointer in |
\fIsubject\fP, a length in bytes in \fIlength\fP, and a starting byte offset | \fIsubject\fP, a length in \fIlength\fP, and a starting offset in |
in \fIstartoffset\fP. If this is negative or greater than the length of the | \fIstartoffset\fP. The units for \fIlength\fP and \fIstartoffset\fP are bytes |
subject, \fBpcre_exec()\fP returns PCRE_ERROR_BADOFFSET. When the starting | for the 8-bit library, 16-bit data items for the 16-bit library, and 32-bit |
offset is zero, the search for a match starts at the beginning of the subject, | data items for the 32-bit library. |
and this is by far the most common case. In UTF-8 mode, the byte offset must | |
point to the start of a UTF-8 character (or the end of the subject). Unlike the | |
pattern string, the subject may contain binary zero bytes. | |
.P |
.P |
|
If \fIstartoffset\fP is negative or greater than the length of the subject, |
|
\fBpcre_exec()\fP returns PCRE_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 offset must point |
|
to the start of a character, or the end of the subject (in UTF-32 mode, one |
|
data unit equals one character, so all offsets are valid). Unlike the pattern |
|
string, the subject may contain binary zeroes. |
|
.P |
A non-zero starting offset is useful when searching for another match in the |
A non-zero starting offset is useful when searching for another match in the |
same subject by calling \fBpcre_exec()\fP again after a previous success. |
same subject by calling \fBpcre_exec()\fP again after a previous success. |
Setting \fIstartoffset\fP differs from just passing over a shortened string and |
Setting \fIstartoffset\fP differs from just passing over a shortened string and |
Line 1864 rounded down.
|
Line 2069 rounded down.
|
When a match is successful, information about captured substrings is returned |
When a match is successful, information about captured substrings is returned |
in pairs of integers, starting at the beginning of \fIovector\fP, and |
in pairs of integers, starting at the beginning of \fIovector\fP, and |
continuing up to two-thirds of its length at the most. The first element of |
continuing up to two-thirds of its length at the most. The first element of |
each pair is set to the byte offset of the first character in a substring, and | each pair is set to the offset of the first character in a substring, and the |
the second is set to the byte offset of the first character after the end of a | second is set to the offset of the first character after the end of a |
substring. \fBNote\fP: these values are always byte offsets, even in UTF-8 | substring. These values are always data unit offsets, even in UTF mode. They |
mode. They are not character counts. | are byte offsets in the 8-bit library, 16-bit data item offsets in the 16-bit |
| library, and 32-bit data item offsets in the 32-bit library. \fBNote\fP: they |
| are not character counts. |
.P |
.P |
The first pair of integers, \fIovector[0]\fP and \fIovector[1]\fP, identify the |
The first pair of integers, \fIovector[0]\fP and \fIovector[1]\fP, identify the |
portion of the subject string matched by the entire pattern. The next pair is |
portion of the subject string matched by the entire pattern. The next pair is |
Line 1882 string that it matched that is returned.
|
Line 2089 string that it matched that is returned.
|
.P |
.P |
If the vector is too small to hold all the captured substring offsets, it is |
If the vector is too small to hold all the captured substring offsets, it is |
used as far as possible (up to two-thirds of its length), and the function |
used as far as possible (up to two-thirds of its length), and the function |
returns a value of zero. If neither the actual string matched not any captured | returns a value of zero. If neither the actual string matched nor any captured |
substrings are of interest, \fBpcre_exec()\fP may be called with \fIovector\fP |
substrings are of interest, \fBpcre_exec()\fP may be called with \fIovector\fP |
passed as NULL and \fIovecsize\fP as zero. However, if the pattern contains |
passed as NULL and \fIovecsize\fP as zero. However, if the pattern contains |
back references and the \fIovector\fP is not big enough to remember the related |
back references and the \fIovector\fP is not big enough to remember the related |
Line 2082 time.
|
Line 2289 time.
|
.sp |
.sp |
PCRE_ERROR_JIT_STACKLIMIT (-27) |
PCRE_ERROR_JIT_STACKLIMIT (-27) |
.sp |
.sp |
This error is returned when a pattern that was successfully studied using the | This error is returned when a pattern that was successfully studied using a |
PCRE_STUDY_JIT_COMPILE option is being matched, but the memory available for | JIT compile option is being matched, but the memory available for the |
the just-in-time processing stack is not large enough. See the | just-in-time processing stack is not large enough. See the |
.\" HREF |
.\" HREF |
\fBpcrejit\fP |
\fBpcrejit\fP |
.\" |
.\" |
documentation for more details. |
documentation for more details. |
.sp |
.sp |
PCRE_ERROR_BADMODE (-28) | PCRE_ERROR_BADMODE (-28) |
.sp |
.sp |
This error is given if a pattern that was compiled by the 8-bit library is |
This error is given if a pattern that was compiled by the 8-bit library is |
passed to a 16-bit library function, or vice versa. | passed to a 16-bit or 32-bit library function, or vice versa. |
.sp |
.sp |
PCRE_ERROR_BADENDIANNESS (-29) | PCRE_ERROR_BADENDIANNESS (-29) |
.sp |
.sp |
This error is given if a pattern that was compiled and saved is reloaded on a |
This error is given if a pattern that was compiled and saved is reloaded on a |
host with different endianness. The utility function |
host with different endianness. The utility function |
\fBpcre_pattern_to_host_byte_order()\fP can be used to convert such a pattern |
\fBpcre_pattern_to_host_byte_order()\fP can be used to convert such a pattern |
so that it runs on the new host. |
so that it runs on the new host. |
|
.sp |
|
PCRE_ERROR_JIT_BADOPTION |
|
.sp |
|
This error is returned when a pattern that was successfully studied using a JIT |
|
compile option 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 |
|
.\" HREF |
|
\fBpcrejit\fP |
|
.\" |
|
documentation for more details. |
|
.sp |
|
PCRE_ERROR_BADLENGTH (-32) |
|
.sp |
|
This error is given if \fBpcre_exec()\fP is called with a negative value for |
|
the \fIlength\fP argument. |
.P |
.P |
Error numbers -16 to -20 and -22 are not used by \fBpcre_exec()\fP. | Error numbers -16 to -20, -22, and 30 are not used by \fBpcre_exec()\fP. |
. |
. |
. |
. |
.\" HTML <a name="badutf8reasons"></a> |
.\" HTML <a name="badutf8reasons"></a> |
Line 2110 Error numbers -16 to -20 and -22 are not used by \fBpc
|
Line 2333 Error numbers -16 to -20 and -22 are not used by \fBpc
|
.rs |
.rs |
.sp |
.sp |
This section applies only to the 8-bit library. The corresponding information |
This section applies only to the 8-bit library. The corresponding information |
for the 16-bit library is given in the | for the 16-bit and 32-bit libraries is given in the |
.\" HREF |
.\" HREF |
\fBpcre16\fP |
\fBpcre16\fP |
.\" |
.\" |
page. | and |
| .\" HREF |
| \fBpcre32\fP |
| .\" |
| pages. |
.P |
.P |
When \fBpcre_exec()\fP returns either PCRE_ERROR_BADUTF8 or |
When \fBpcre_exec()\fP returns either PCRE_ERROR_BADUTF8 or |
PCRE_ERROR_SHORTUTF8, and the size of the output vector (\fIovecsize\fP) is at |
PCRE_ERROR_SHORTUTF8, and the size of the output vector (\fIovecsize\fP) is at |
Line 2184 character.
|
Line 2411 character.
|
.sp |
.sp |
The first byte of a character has the value 0xfe or 0xff. These values can |
The first byte of a character has the value 0xfe or 0xff. These values can |
never occur in a valid UTF-8 string. |
never occur in a valid UTF-8 string. |
|
.sp |
|
PCRE_UTF8_ERR22 |
|
.sp |
|
This error code was formerly used when the presence of a so-called |
|
"non-character" caused an error. Unicode corrigendum #9 makes it clear that |
|
such characters should not cause a string to be rejected, and so this code is |
|
no longer in use and is never returned. |
. |
. |
. |
. |
.SH "EXTRACTING CAPTURED SUBSTRINGS BY NUMBER" |
.SH "EXTRACTING CAPTURED SUBSTRINGS BY NUMBER" |
Line 2620 When a recursive subpattern is processed, the matching
|
Line 2854 When a recursive subpattern is processed, the matching
|
recursively, using private vectors for \fIovector\fP and \fIworkspace\fP. This |
recursively, using private vectors for \fIovector\fP and \fIworkspace\fP. This |
error is given if the output vector is not large enough. This should be |
error is given if the output vector is not large enough. This should be |
extremely rare, as a vector of size 1000 is used. |
extremely rare, as a vector of size 1000 is used. |
|
.sp |
|
PCRE_ERROR_DFA_BADRESTART (-30) |
|
.sp |
|
When \fBpcre_dfa_exec()\fP is called with the \fBPCRE_DFA_RESTART\fP 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. |
. |
. |
. |
. |
.SH "SEE ALSO" |
.SH "SEE ALSO" |
.rs |
.rs |
.sp |
.sp |
\fBpcre16\fP(3), \fBpcrebuild\fP(3), \fBpcrecallout\fP(3), \fBpcrecpp(3)\fP(3), | \fBpcre16\fP(3), \fBpcre32\fP(3), \fBpcrebuild\fP(3), \fBpcrecallout\fP(3), |
\fBpcrematching\fP(3), \fBpcrepartial\fP(3), \fBpcreposix\fP(3), | \fBpcrecpp(3)\fP(3), \fBpcrematching\fP(3), \fBpcrepartial\fP(3), |
\fBpcreprecompile\fP(3), \fBpcresample\fP(3), \fBpcrestack\fP(3). | \fBpcreposix\fP(3), \fBpcreprecompile\fP(3), \fBpcresample\fP(3), |
| \fBpcrestack\fP(3). |
. |
. |
. |
. |
.SH AUTHOR |
.SH AUTHOR |
Line 2644 Cambridge CB2 3QH, England.
|
Line 2886 Cambridge CB2 3QH, England.
|
.rs |
.rs |
.sp |
.sp |
.nf |
.nf |
Last updated: 21 January 2012 | Last updated: 12 May 2013 |
Copyright (c) 1997-2012 University of Cambridge. | Copyright (c) 1997-2013 University of Cambridge. |
.fi |
.fi |