/[pcre]/code/trunk/doc/pcreapi.3
ViewVC logotype

Diff of /code/trunk/doc/pcreapi.3

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 788 by ph10, Tue Dec 6 15:38:01 2011 UTC revision 1113 by chpe, Tue Oct 16 15:57:12 2012 UTC
# Line 1  Line 1 
1  .TH PCREAPI 3  .TH PCREAPI 3 "07 September 2012" "PCRE 8.32"
2  .SH NAME  .SH NAME
3  PCRE - Perl-compatible regular expressions  PCRE - Perl-compatible regular expressions
4    .sp
5    .B #include <pcre.h>
6    .
7    .
8  .SH "PCRE NATIVE API BASIC FUNCTIONS"  .SH "PCRE NATIVE API BASIC FUNCTIONS"
9  .rs  .rs
10  .sp  .sp
 .B #include <pcre.h>  
 .PP  
11  .SM  .SM
12  .B pcre *pcre_compile(const char *\fIpattern\fP, int \fIoptions\fP,  .B pcre *pcre_compile(const char *\fIpattern\fP, int \fIoptions\fP,
13  .ti +5n  .ti +5n
# Line 32  PCRE - Perl-compatible regular expressio Line 34  PCRE - Perl-compatible regular expressio
34  .B "const char *\fIsubject\fP," int \fIlength\fP, int \fIstartoffset\fP,  .B "const char *\fIsubject\fP," int \fIlength\fP, int \fIstartoffset\fP,
35  .ti +5n  .ti +5n
36  .B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);  .B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);
 .  
 .  
 .SH "PCRE NATIVE API AUXILIARY FUNCTIONS"  
 .rs  
 .sp  
 .B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP);  
 .PP  
 .B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP);  
 .PP  
 .B void pcre_assign_jit_stack(pcre_extra *\fIextra\fP,  
 .ti +5n  
 .B pcre_jit_callback \fIcallback\fP, void *\fIdata\fP);  
37  .PP  .PP
38  .B int pcre_dfa_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"  .B int pcre_dfa_exec(const pcre *\fIcode\fP, "const pcre_extra *\fIextra\fP,"
39  .ti +5n  .ti +5n
# Line 52  PCRE - Perl-compatible regular expressio Line 42  PCRE - Perl-compatible regular expressio
42  .B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,  .B int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP,
43  .ti +5n  .ti +5n
44  .B int *\fIworkspace\fP, int \fIwscount\fP);  .B int *\fIworkspace\fP, int \fIwscount\fP);
45  .PP  .
46    .
47    .SH "PCRE NATIVE API STRING EXTRACTION FUNCTIONS"
48    .rs
49    .sp
50  .B int pcre_copy_named_substring(const pcre *\fIcode\fP,  .B int pcre_copy_named_substring(const pcre *\fIcode\fP,
51  .ti +5n  .ti +5n
52  .B const char *\fIsubject\fP, int *\fIovector\fP,  .B const char *\fIsubject\fP, int *\fIovector\fP,
# Line 96  PCRE - Perl-compatible regular expressio Line 90  PCRE - Perl-compatible regular expressio
90  .B void pcre_free_substring(const char *\fIstringptr\fP);  .B void pcre_free_substring(const char *\fIstringptr\fP);
91  .PP  .PP
92  .B void pcre_free_substring_list(const char **\fIstringptr\fP);  .B void pcre_free_substring_list(const char **\fIstringptr\fP);
93    .
94    .
95    .SH "PCRE NATIVE API AUXILIARY FUNCTIONS"
96    .rs
97    .sp
98    .B pcre_jit_stack *pcre_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP);
99    .PP
100    .B void pcre_jit_stack_free(pcre_jit_stack *\fIstack\fP);
101    .PP
102    .B void pcre_assign_jit_stack(pcre_extra *\fIextra\fP,
103    .ti +5n
104    .B pcre_jit_callback \fIcallback\fP, void *\fIdata\fP);
105  .PP  .PP
106  .B const unsigned char *pcre_maketables(void);  .B const unsigned char *pcre_maketables(void);
107  .PP  .PP
# Line 103  PCRE - Perl-compatible regular expressio Line 109  PCRE - Perl-compatible regular expressio
109  .ti +5n  .ti +5n
110  .B int \fIwhat\fP, void *\fIwhere\fP);  .B int \fIwhat\fP, void *\fIwhere\fP);
111  .PP  .PP
 .B int pcre_info(const pcre *\fIcode\fP, int *\fIoptptr\fP, int  
 .B *\fIfirstcharptr\fP);  
 .PP  
112  .B int pcre_refcount(pcre *\fIcode\fP, int \fIadjust\fP);  .B int pcre_refcount(pcre *\fIcode\fP, int \fIadjust\fP);
113  .PP  .PP
114  .B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);  .B int pcre_config(int \fIwhat\fP, void *\fIwhere\fP);
115  .PP  .PP
116  .B char *pcre_version(void);  .B const char *pcre_version(void);
117    .PP
118    .B int pcre_pattern_to_host_byte_order(pcre *\fIcode\fP,
119    .ti +5n
120    .B pcre_extra *\fIextra\fP, const unsigned char *\fItables\fP);
121  .  .
122  .  .
123  .SH "PCRE NATIVE API INDIRECTED FUNCTIONS"  .SH "PCRE NATIVE API INDIRECTED FUNCTIONS"
# Line 127  PCRE - Perl-compatible regular expressio Line 134  PCRE - Perl-compatible regular expressio
134  .B int (*pcre_callout)(pcre_callout_block *);  .B int (*pcre_callout)(pcre_callout_block *);
135  .  .
136  .  .
137    .SH "PCRE 8-BIT, 16-BIT AND 32-BIT LIBRARIES"
138    .rs
139    .sp
140    From release 8.30, PCRE can be compiled as a library for handling 16-bit
141    character strings as well as, or instead of, the original library that handles
142    8-bit character strings. From release 8.32, PCRE can also be compiled as a
143    library for handling 32-bit character strings. To avoid too much complication,
144    this document describes the 8-bit versions of the functions, with only
145    occasional references to the 16-bit and 32-bit libraries.
146    .P
147    The 16-bit functions operate in the same way as their 8-bit counterparts; they
148    just use different data types for their arguments and results, and their names
149    start with \fBpcre16_\fP instead of \fBpcre_\fP. For every option that has UTF8
150    in its name (for example, PCRE_UTF8), there is a corresponding 16-bit name with
151    UTF8 replaced by UTF16. This facility is in fact just cosmetic; the 16-bit
152    option names define the same bit values.
153    .P
154    The 32-bit functions operate in the same way as their 8-bit counterparts; they
155    just use different data types for their arguments and results, and their names
156    start with \fBpcre32_\fP instead of \fBpcre_\fP. For every option that has UTF8
157    in its name (for example, PCRE_UTF8), there is a corresponding 32-bit name with
158    UTF8 replaced by UTF32. This facility is in fact just cosmetic; the 32-bit
159    option names define the same bit values.
160    .P
161    References to bytes and UTF-8 in this document should be read as references to
162    16-bit data quantities and UTF-16 when using the 16-bit library, unless
163    specified otherwise. More details of the specific differences for the 16-bit
164    library are given in the
165    .\" HREF
166    \fBpcre16\fP
167    .\"
168    page.
169    .
170    .P
171    References to bytes and UTF-8 in this document should be read as references to
172    32-bit data quantities and UTF-32 when using the 32-bit library, unless
173    specified otherwise. More details of the specific differences for the 32-bit
174    library are given in the
175    .\" HREF
176    \fBpcre32\fP
177    .\"
178    page.
179    .
180    .
181  .SH "PCRE API OVERVIEW"  .SH "PCRE API OVERVIEW"
182  .rs  .rs
183  .sp  .sp
184  PCRE has its own native API, which is described in this document. There are  PCRE has its own native API, which is described in this document. There are
185  also some wrapper functions that correspond to the POSIX regular expression  also some wrapper functions (for the 8-bit library only) that correspond to the
186  API, but they do not give access to all the functionality. They are described  POSIX regular expression API, but they do not give access to all the
187  in the  functionality. They are described in the
188  .\" HREF  .\" HREF
189  \fBpcreposix\fP  \fBpcreposix\fP
190  .\"  .\"
191  documentation. Both of these APIs define a set of C function calls. A C++  documentation. Both of these APIs define a set of C function calls. A C++
192  wrapper is also distributed with PCRE. It is documented in the  wrapper (again for the 8-bit library only) is also distributed with PCRE. It is
193    documented in the
194  .\" HREF  .\" HREF
195  \fBpcrecpp\fP  \fBpcrecpp\fP
196  .\"  .\"
197  page.  page.
198  .P  .P
199  The native API C function prototypes are defined in the header file  The native API C function prototypes are defined in the header file
200  \fBpcre.h\fP, and on Unix systems the library itself is called \fBlibpcre\fP.  \fBpcre.h\fP, and on Unix-like systems the (8-bit) library itself is called
201  It can normally be accessed by adding \fB-lpcre\fP to the command for linking  \fBlibpcre\fP. It can normally be accessed by adding \fB-lpcre\fP to the
202  an application that uses PCRE. The header file defines the macros PCRE_MAJOR  command for linking an application that uses PCRE. The header file defines the
203  and PCRE_MINOR to contain the major and minor release numbers for the library.  macros PCRE_MAJOR and PCRE_MINOR to contain the major and minor release numbers
204  Applications can use these to include support for different releases of PCRE.  for the library. Applications can use these to include support for different
205    releases of PCRE.
206  .P  .P
207  In a Windows environment, if you want to statically link an application program  In a Windows environment, if you want to statically link an application program
208  against a non-dll \fBpcre.a\fP file, you must define PCRE_STATIC before  against a non-dll \fBpcre.a\fP file, you must define PCRE_STATIC before
# Line 218  specialist use. Most commonly, no specia Line 271  specialist use. Most commonly, no specia
271  internal tables that are generated when PCRE is built are used.  internal tables that are generated when PCRE is built are used.
272  .P  .P
273  The function \fBpcre_fullinfo()\fP is used to find out information about a  The function \fBpcre_fullinfo()\fP is used to find out information about a
274  compiled pattern; \fBpcre_info()\fP is an obsolete version that returns only  compiled pattern. The function \fBpcre_version()\fP returns a pointer to a
275  some of the available information, but is retained for backwards compatibility.  string containing the version of PCRE and its date of release.
 The function \fBpcre_version()\fP returns a pointer to a string containing the  
 version of PCRE and its date of release.  
276  .P  .P
277  The function \fBpcre_refcount()\fP maintains a reference count in a data block  The function \fBpcre_refcount()\fP maintains a reference count in a data block
278  containing a compiled pattern. This is provided for the benefit of  containing a compiled pattern. This is provided for the benefit of
# Line 269  PCRE supports five different conventions Line 320  PCRE supports five different conventions
320  strings: a single CR (carriage return) character, a single LF (linefeed)  strings: a single CR (carriage return) character, a single LF (linefeed)
321  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
322  Unicode newline sequence. The Unicode newline sequences are the three just  Unicode newline sequence. The Unicode newline sequences are the three just
323  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,
324  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
325  (paragraph separator, U+2029).  (paragraph separator, U+2029).
326  .P  .P
# Line 332  which it was compiled. Details are given Line 383  which it was compiled. Details are given
383  .\" HREF  .\" HREF
384  \fBpcreprecompile\fP  \fBpcreprecompile\fP
385  .\"  .\"
386  documentation. However, compiling a regular expression with one version of PCRE  documentation, which includes a description of the
387  for use with a different version is not guaranteed to work and may cause  \fBpcre_pattern_to_host_byte_order()\fP function. However, compiling a regular
388  crashes.  expression with one version of PCRE for use with a different version is not
389    guaranteed to work and may cause crashes.
390  .  .
391  .  .
392  .SH "CHECKING BUILD-TIME OPTIONS"  .SH "CHECKING BUILD-TIME OPTIONS"
# Line 351  documentation has more details about the Line 403  documentation has more details about the
403  .P  .P
404  The first argument for \fBpcre_config()\fP is an integer, specifying which  The first argument for \fBpcre_config()\fP is an integer, specifying which
405  information is required; the second argument is a pointer to a variable into  information is required; the second argument is a pointer to a variable into
406  which the information is placed. The following information is available:  which the information is placed. The returned value is zero on success, or the
407    negative error code PCRE_ERROR_BADOPTION if the value in the first argument is
408    not recognized. The following information is available:
409  .sp  .sp
410    PCRE_CONFIG_UTF8    PCRE_CONFIG_UTF8
411  .sp  .sp
412  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;
413  otherwise it is set to zero.  otherwise it is set to zero. This value should normally be given to the 8-bit
414    version of this function, \fBpcre_config()\fP. If it is given to the 16-bit
415    or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
416    .sp
417      PCRE_CONFIG_UTF16
418    .sp
419    The output is an integer that is set to one if UTF-16 support is available;
420    otherwise it is set to zero. This value should normally be given to the 16-bit
421    version of this function, \fBpcre16_config()\fP. If it is given to the 8-bit
422    or 32-bit version of this function, the result is PCRE_ERROR_BADOPTION.
423    .sp
424      PCRE_CONFIG_UTF32
425    .sp
426    The output is an integer that is set to one if UTF-32 support is available;
427    otherwise it is set to zero. This value should normally be given to the 32-bit
428    version of this function, \fBpcre32_config()\fP. If it is given to the 8-bit
429    or 16-bit version of this function, the result is PCRE_ERROR_BADOPTION.
430  .sp  .sp
431    PCRE_CONFIG_UNICODE_PROPERTIES    PCRE_CONFIG_UNICODE_PROPERTIES
432  .sp  .sp
# Line 368  properties is available; otherwise it is Line 438  properties is available; otherwise it is
438  The output is an integer that is set to one if support for just-in-time  The output is an integer that is set to one if support for just-in-time
439  compiling is available; otherwise it is set to zero.  compiling is available; otherwise it is set to zero.
440  .sp  .sp
441      PCRE_CONFIG_JITTARGET
442    .sp
443    The output is a pointer to a zero-terminated "const char *" string. If JIT
444    support is available, the string contains the name of the architecture for
445    which the JIT compiler is configured, for example "x86 32bit (little endian +
446    unaligned)". If JIT support is not available, the result is NULL.
447    .sp
448    PCRE_CONFIG_NEWLINE    PCRE_CONFIG_NEWLINE
449  .sp  .sp
450  The output is an integer whose value specifies the default character sequence  The output is an integer whose value specifies the default character sequence
451  that is recognized as meaning "newline". The four values that are supported  that is recognized as meaning "newline". The values that are supported in
452  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
453  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
454  environments. The default should normally correspond to the standard sequence  same values. However, the value for LF is normally 21, though some EBCDIC
455  for your operating system.  environments use 37. The corresponding values for CRLF are 3349 and 3365. The
456    default should normally correspond to the standard sequence for your operating
457    system.
458  .sp  .sp
459    PCRE_CONFIG_BSR    PCRE_CONFIG_BSR
460  .sp  .sp
# Line 387  or CRLF. The default can be overridden w Line 466  or CRLF. The default can be overridden w
466    PCRE_CONFIG_LINK_SIZE    PCRE_CONFIG_LINK_SIZE
467  .sp  .sp
468  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
469  linkage in compiled regular expressions. The value is 2, 3, or 4. Larger values  linkage in compiled regular expressions. For the 8-bit library, the value can
470  allow larger regular expressions to be compiled, at the expense of slower  be 2, 3, or 4. For the 16-bit library, the value is either 2 or 4 and is still
471  matching. The default value of 2 is sufficient for all but the most massive  a number of bytes. For the 32-bit library, the value is either 2 or 4 and is
472  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
473    most massive patterns, since it allows the compiled pattern to be up to 64K in
474    size. Larger values allow larger regular expressions to be compiled, at the
475    expense of slower matching.
476  .sp  .sp
477    PCRE_CONFIG_POSIX_MALLOC_THRESHOLD    PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
478  .sp  .sp
# Line 473  documentation). For those options that c Line 555  documentation). For those options that c
555  the pattern, the contents of the \fIoptions\fP argument specifies their  the pattern, the contents of the \fIoptions\fP argument specifies their
556  settings at the start of compilation and execution. The PCRE_ANCHORED,  settings at the start of compilation and execution. The PCRE_ANCHORED,
557  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
558  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
559  compile time.  compile time.
560  .P  .P
561  If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.  If \fIerrptr\fP is NULL, \fBpcre_compile()\fP returns NULL immediately.
# Line 484  not try to free it. Normally, the offset Line 566  not try to free it. Normally, the offset
566  byte that was being processed when the error was discovered is placed in the  byte that was being processed when the error was discovered is placed in the
567  variable pointed to by \fIerroffset\fP, which must not be NULL (if it is, an  variable pointed to by \fIerroffset\fP, which must not be NULL (if it is, an
568  immediate error is given). However, for an invalid UTF-8 string, the offset is  immediate error is given). However, for an invalid UTF-8 string, the offset is
569  that of the first byte of the failing character. Also, some errors are not  that of the first byte of the failing character.
 detected until checks are carried out when the whole pattern has been scanned;  
 in these cases the offset passed back is the length of the pattern.  
570  .P  .P
571  Note that the offset is in bytes, not characters, even in UTF-8 mode. It may  Some errors are not detected until the whole pattern has been scanned; in these
572  sometimes point into the middle of a UTF-8 character.  cases, the offset passed back is the length of the pattern. Note that the
573    offset is in bytes, not characters, even in UTF-8 mode. It may sometimes point
574    into the middle of a UTF-8 character.
575  .P  .P
576  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
577  \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 589  documentation. Line 671  documentation.
671  .sp  .sp
672    PCRE_EXTENDED    PCRE_EXTENDED
673  .sp  .sp
674  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
675  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
676  include the VT character (code 11). In addition, characters between an  include the VT character (code 11). In addition, characters between an
677  unescaped # outside a character class and the next newline, inclusive, are also  unescaped # outside a character class and the next newline, inclusive, are also
678  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 608  comment is a literal newline sequence in Line 690  comment is a literal newline sequence in
690  happen to represent a newline do not count.  happen to represent a newline do not count.
691  .P  .P
692  This option makes it possible to include comments inside complicated patterns.  This option makes it possible to include comments inside complicated patterns.
693  Note, however, that this applies only to data characters. Whitespace characters  Note, however, that this applies only to data characters. White space characters
694  may never appear within special character sequences in a pattern, for example  may never appear within special character sequences in a pattern, for example
695  within the sequence (?( that introduces a conditional subpattern.  within the sequence (?( that introduces a conditional subpattern.
696  .sp  .sp
# Line 686  indicated by a single character (CR or L Line 768  indicated by a single character (CR or L
768  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
769  CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three  CRLF sequence. Setting PCRE_NEWLINE_ANYCRLF specifies that any of the three
770  preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies  preceding sequences should be recognized. Setting PCRE_NEWLINE_ANY specifies
771  that any Unicode newline sequence should be recognized. The Unicode newline  that any Unicode newline sequence should be recognized.
772  sequences are the three just mentioned, plus the single characters VT (vertical  .P
773  tab, U+000B), FF (formfeed, U+000C), NEL (next line, U+0085), LS (line  In an ASCII/Unicode environment, the Unicode newline sequences are the three
774  separator, U+2028), and PS (paragraph separator, U+2029). The last two are  just mentioned, plus the single characters VT (vertical tab, U+000B), FF (form
775    feed, U+000C), NEL (next line, U+0085), LS (line separator, U+2028), and PS
776    (paragraph separator, U+2029). For the 8-bit library, the last two are
777  recognized only in UTF-8 mode.  recognized only in UTF-8 mode.
778  .P  .P
779    When PCRE is compiled to run in an EBCDIC (mainframe) environment, the code for
780    CR is 0x0d, the same as ASCII. However, the character code for LF is normally
781    0x15, though in some EBCDIC environments 0x25 is used. Whichever of these is
782    not LF is made to correspond to Unicode's NEL character. EBCDIC codes are all
783    less than 256. For more details, see the
784    .\" HREF
785    \fBpcrebuild\fP
786    .\"
787    documentation.
788    .P
789  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
790  as a number, giving eight possibilities. Currently only six are used (default  as a number, giving eight possibilities. Currently only six are used (default
791  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 700  PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is Line 794  PCRE_NEWLINE_CR with PCRE_NEWLINE_LF is
794  other combinations may yield unused numbers and cause an error.  other combinations may yield unused numbers and cause an error.
795  .P  .P
796  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
797  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,
798  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
799  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
800  other circumstances, line break sequences in patterns are treated as literal  other circumstances, line break sequences in patterns are treated as literal
# Line 755  with Perl. It can also be set by a (?U) Line 849  with Perl. It can also be set by a (?U)
849    PCRE_UTF8    PCRE_UTF8
850  .sp  .sp
851  This option causes PCRE to regard both the pattern and the subject as strings  This option causes PCRE to regard both the pattern and the subject as strings
852  of UTF-8 characters instead of single-byte character strings. However, it is  of UTF-8 characters instead of single-byte strings. However, it is available
853  available only when PCRE is built to include UTF-8 support. If not, the use  only when PCRE is built to include UTF support. If not, the use of this option
854  of this option provokes an error. Details of how this option changes the  provokes an error. Details of how this option changes the behaviour of PCRE are
855  behaviour of PCRE are given in the  given in the
856  .\" HREF  .\" HREF
857  \fBpcreunicode\fP  \fBpcreunicode\fP
858  .\"  .\"
# Line 766  page. Line 860  page.
860  .sp  .sp
861    PCRE_NO_UTF8_CHECK    PCRE_NO_UTF8_CHECK
862  .sp  .sp
863  When PCRE_UTF8 is set, the validity of the pattern as a UTF-8 string is  When PCRE_UTF8 is set, the validity of the pattern as a UTF-8
864  automatically checked. There is a discussion about the  string is automatically checked. There is a discussion about the
865  .\" HTML <a href="pcre.html#utf8strings">  .\" HTML <a href="pcreunicode.html#utf8strings">
866  .\" </a>  .\" </a>
867  validity of UTF-8 strings  validity of UTF-8 strings
868  .\"  .\"
869  in the main  in the
870  .\" HREF  .\" HREF
871  \fBpcre\fP  \fBpcreunicode\fP
872  .\"  .\"
873  page. If an invalid UTF-8 sequence of bytes is found, \fBpcre_compile()\fP  page. If an invalid UTF-8 sequence is found, \fBpcre_compile()\fP returns an
874  returns an error. If you already know that your pattern is valid, and you want  error. If you already know that your pattern is valid, and you want to skip
875  to skip this check for performance reasons, you can set the PCRE_NO_UTF8_CHECK  this check for performance reasons, you can set the PCRE_NO_UTF8_CHECK option.
876  option. When it is set, the effect of passing an invalid UTF-8 string as a  When it is set, the effect of passing an invalid UTF-8 string as a pattern is
877  pattern is undefined. It may cause your program to crash. Note that this option  undefined. It may cause your program to crash. Note that this option can also
878  can also be passed to \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP, to suppress  be passed to \fBpcre_exec()\fP and \fBpcre_dfa_exec()\fP, to suppress the
879  the UTF-8 validity checking of subject strings.  validity checking of subject strings.
880  .  .
881  .  .
882  .SH "COMPILATION ERROR CODES"  .SH "COMPILATION ERROR CODES"
# Line 790  the UTF-8 validity checking of subject s Line 884  the UTF-8 validity checking of subject s
884  .sp  .sp
885  The following table lists the error codes than may be returned by  The following table lists the error codes than may be returned by
886  \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
887  both compiling functions. As PCRE has developed, some error codes have fallen  both compiling functions. Note that error messages are always 8-bit ASCII
888  out of use. To avoid confusion, they have not been re-used.  strings, even in 16-bit or 32-bit mode. As PCRE has developed, some error codes
889    have fallen out of use. To avoid confusion, they have not been re-used.
890  .sp  .sp
891     0  no error     0  no error
892     1  \e at end of pattern     1  \e at end of pattern
# Line 825  out of use. To avoid confusion, they hav Line 920  out of use. To avoid confusion, they hav
920    29  (?R or (?[+-]digits must be followed by )    29  (?R or (?[+-]digits must be followed by )
921    30  unknown POSIX class name    30  unknown POSIX class name
922    31  POSIX collating elements are not supported    31  POSIX collating elements are not supported
923    32  this version of PCRE is not compiled with PCRE_UTF8 support    32  this version of PCRE is compiled without UTF support
924    33  [this code is not in use]    33  [this code is not in use]
925    34  character value in \ex{...} sequence is too large    34  character value in \ex{...} sequence is too large
926    35  invalid condition (?(0)    35  invalid condition (?(0)
# Line 837  out of use. To avoid confusion, they hav Line 932  out of use. To avoid confusion, they hav
932    41  unrecognized character after (?P    41  unrecognized character after (?P
933    42  syntax error in subpattern name (missing terminator)    42  syntax error in subpattern name (missing terminator)
934    43  two named subpatterns have the same name    43  two named subpatterns have the same name
935    44  invalid UTF-8 string    44  invalid UTF-8 string (specifically UTF-8)
936    45  support for \eP, \ep, and \eX has not been compiled    45  support for \eP, \ep, and \eX has not been compiled
937    46  malformed \eP or \ep sequence    46  malformed \eP or \ep sequence
938    47  unknown property name after \eP or \ep    47  unknown property name after \eP or \ep
939    48  subpattern name is too long (maximum 32 characters)    48  subpattern name is too long (maximum 32 characters)
940    49  too many named subpatterns (maximum 10000)    49  too many named subpatterns (maximum 10000)
941    50  [this code is not in use]    50  [this code is not in use]
942    51  octal value is greater than \e377 (not in UTF-8 mode)    51  octal value is greater than \e377 in 8-bit non-UTF-8 mode
943    52  internal error: overran compiling workspace    52  internal error: overran compiling workspace
944    53  internal error: previously-checked referenced subpattern    53  internal error: previously-checked referenced subpattern
945          not found          not found
# Line 863  out of use. To avoid confusion, they hav Line 958  out of use. To avoid confusion, they hav
958    65  different names for subpatterns of the same number are    65  different names for subpatterns of the same number are
959          not allowed          not allowed
960    66  (*MARK) must have an argument    66  (*MARK) must have an argument
961    67  this version of PCRE is not compiled with PCRE_UCP support    67  this version of PCRE is not compiled with Unicode property
962            support
963    68  \ec must be followed by an ASCII character    68  \ec must be followed by an ASCII character
964    69  \ek is not followed by a braced, angle-bracketed, or quoted name    69  \ek is not followed by a braced, angle-bracketed, or quoted name
965      70  internal error: unknown opcode in find_fixedlength()
966      71  \eN is not supported in a class
967      72  too many forward references
968      73  disallowed Unicode code point (>= 0xd800 && <= 0xdfff)
969      74  invalid UTF-16 string (specifically UTF-16)
970      75  name is too long in (*MARK), (*PRUNE), (*SKIP), or (*THEN)
971      76  character value in \eu.... sequence is too large
972      77  invalid UTF-32 string (specifically UTF-32)
973  .sp  .sp
974  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
975  be used if the limits were changed when PCRE was built.  be used if the limits were changed when PCRE was built.
# Line 898  below Line 1002  below
1002  in the section on matching a pattern.  in the section on matching a pattern.
1003  .P  .P
1004  If studying the pattern does not produce any useful information,  If studying the pattern does not produce any useful information,
1005  \fBpcre_study()\fP returns NULL. In that circumstance, if the calling program  \fBpcre_study()\fP returns NULL by default. In that circumstance, if the
1006  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
1007  \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,
1008  .P  if \fBpcre_study()\fP is called with the PCRE_STUDY_EXTRA_NEEDED option, it
1009  The second argument of \fBpcre_study()\fP contains option bits. There is only  returns a \fBpcre_extra\fP block even if studying did not find any additional
1010  one option: PCRE_STUDY_JIT_COMPILE. If this is set, and the just-in-time  information. It may still return NULL, however, if an error occurs in
1011  compiler is available, the pattern is further compiled into machine code that  \fBpcre_study()\fP.
1012  executes much faster than the \fBpcre_exec()\fP matching function. If  .P
1013  the just-in-time compiler is not available, this option is ignored. All other  The second argument of \fBpcre_study()\fP contains option bits. There are three
1014  bits in the \fIoptions\fP argument must be zero.  further options in addition to PCRE_STUDY_EXTRA_NEEDED:
1015    .sp
1016      PCRE_STUDY_JIT_COMPILE
1017      PCRE_STUDY_JIT_PARTIAL_HARD_COMPILE
1018      PCRE_STUDY_JIT_PARTIAL_SOFT_COMPILE
1019    .sp
1020    If any of these are set, and the just-in-time compiler is available, the
1021    pattern is further compiled into machine code that executes much faster than
1022    the \fBpcre_exec()\fP interpretive matching function. If the just-in-time
1023    compiler is not available, these options are ignored. All undefined bits in the
1024    \fIoptions\fP argument must be zero.
1025  .P  .P
1026  JIT compilation is a heavyweight optimization. It can take some time for  JIT compilation is a heavyweight optimization. It can take some time for
1027  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 931  When you are finished with a pattern, yo Line 1045  When you are finished with a pattern, yo
1045  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
1046  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
1047  \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
1048  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
1049  new function when convenient.  function when convenient.
1050  .P  .P
1051  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
1052  real application there should be tests for errors):  real application there should be tests for errors):
# Line 954  real application there should be tests f Line 1068  real application there should be tests f
1068  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
1069  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
1070  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
1071  guarantee that no shorter strings match. The value is used by  guarantee that no shorter strings match. The value is used to avoid wasting
1072  \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
1073  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.  
1074  .P  .P
1075  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
1076  single fixed starting character. A bitmap of possible starting bytes is  single fixed starting character. A bitmap of possible starting bytes is
1077  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
1078  matching.  matching. (In 16-bit mode, the bitmap is used for 16-bit values less than 256.
1079    In 32-bit mode, the bitmap is used for 32-bit values less than 256.)
1080  .P  .P
1081  These two optimizations apply to both \fBpcre_exec()\fP and  These two optimizations apply to both \fBpcre_exec()\fP and
1082  \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.
1083  \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
1084  just-in-time compiling is successful. The optimizations can be disabled by  when calling \fBpcre_exec()\fP or \fBpcre_dfa_exec()\fP, but if this is done,
1085  setting the PCRE_NO_START_OPTIMIZE option when calling \fBpcre_exec()\fP or  JIT execution is also disabled. You might want to do this if your pattern
1086  \fBpcre_dfa_exec()\fP. You might want to do this if your pattern contains  contains callouts or (*MARK) and you want to make use of these facilities in
1087  callouts or (*MARK) (which cannot be handled by the JIT compiler), and you want  cases where matching fails. See the discussion of PCRE_NO_START_OPTIMIZE
 to make use of these facilities in cases where matching fails. See the  
 discussion of PCRE_NO_START_OPTIMIZE  
1088  .\" HTML <a href="#execoptions">  .\" HTML <a href="#execoptions">
1089  .\" </a>  .\" </a>
1090  below.  below.
# Line 985  below. Line 1097  below.
1097  .sp  .sp
1098  PCRE handles caseless matching, and determines whether characters are letters,  PCRE handles caseless matching, and determines whether characters are letters,
1099  digits, or whatever, by reference to a set of tables, indexed by character  digits, or whatever, by reference to a set of tables, indexed by character
1100  value. When running in UTF-8 mode, this applies only to characters with codes  value. When running in UTF-8 mode, this applies only to characters
1101  less than 128. By default, higher-valued codes never match escapes such as \ew  with codes less than 128. By default, higher-valued codes never match escapes
1102  or \ed, but they can be tested with \ep if PCRE is built with Unicode character  such as \ew or \ed, but they can be tested with \ep if PCRE is built with
1103  property support. Alternatively, the PCRE_UCP option can be set at compile  Unicode character property support. Alternatively, the PCRE_UCP option can be
1104  time; this causes \ew and friends to use Unicode property support instead of  set at compile time; this causes \ew and friends to use Unicode property
1105  built-in tables. The use of locales with Unicode is discouraged. If you are  support instead of built-in tables. The use of locales with Unicode is
1106  handling characters with codes greater than 128, you should either use UTF-8  discouraged. If you are handling characters with codes greater than 128, you
1107  and Unicode, or use locales, but not try to mix the two.  should either use UTF-8 and Unicode, or use locales, but not try to mix the
1108    two.
1109  .P  .P
1110  PCRE contains an internal set of tables that are used when the final argument  PCRE contains an internal set of tables that are used when the final argument
1111  of \fBpcre_compile()\fP is NULL. These are sufficient for many applications.  of \fBpcre_compile()\fP is NULL. These are sufficient for many applications.
# Line 1046  below in the section on matching a patte Line 1159  below in the section on matching a patte
1159  .B int \fIwhat\fP, void *\fIwhere\fP);  .B int \fIwhat\fP, void *\fIwhere\fP);
1160  .PP  .PP
1161  The \fBpcre_fullinfo()\fP function returns information about a compiled  The \fBpcre_fullinfo()\fP function returns information about a compiled
1162  pattern. It replaces the obsolete \fBpcre_info()\fP function, which is  pattern. It replaces the \fBpcre_info()\fP function, which was removed from the
1163  nevertheless retained for backwards compability (and is documented below).  library at version 8.30, after more than 10 years of obsolescence.
1164  .P  .P
1165  The first argument for \fBpcre_fullinfo()\fP is a pointer to the compiled  The first argument for \fBpcre_fullinfo()\fP is a pointer to the compiled
1166  pattern. The second argument is the result of \fBpcre_study()\fP, or NULL if  pattern. The second argument is the result of \fBpcre_study()\fP, or NULL if
# Line 1056  information is required, and the fourth Line 1169  information is required, and the fourth
1169  to receive the data. The yield of the function is zero for success, or one of  to receive the data. The yield of the function is zero for success, or one of
1170  the following negative numbers:  the following negative numbers:
1171  .sp  .sp
1172    PCRE_ERROR_NULL       the argument \fIcode\fP was NULL    PCRE_ERROR_NULL           the argument \fIcode\fP was NULL
1173                          the argument \fIwhere\fP was NULL                              the argument \fIwhere\fP was NULL
1174    PCRE_ERROR_BADMAGIC   the "magic number" was not found    PCRE_ERROR_BADMAGIC       the "magic number" was not found
1175    PCRE_ERROR_BADOPTION  the value of \fIwhat\fP was invalid    PCRE_ERROR_BADENDIANNESS  the pattern was compiled with different
1176                                endianness
1177      PCRE_ERROR_BADOPTION      the value of \fIwhat\fP was invalid
1178  .sp  .sp
1179  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
1180  check against passing an arbitrary memory pointer. Here is a typical call of  check against passing an arbitrary memory pointer. The endianness error can
1181  \fBpcre_fullinfo()\fP, to obtain the length of the compiled pattern:  occur if a compiled pattern is saved and reloaded on a different host. Here is
1182    a typical call of \fBpcre_fullinfo()\fP, to obtain the length of the compiled
1183    pattern:
1184  .sp  .sp
1185    int rc;    int rc;
1186    size_t length;    size_t length;
# Line 1097  a NULL table pointer. Line 1214  a NULL table pointer.
1214  .sp  .sp
1215    PCRE_INFO_FIRSTBYTE    PCRE_INFO_FIRSTBYTE
1216  .sp  .sp
1217  Return information about the first byte of any matched string, for a  Return information about the first data unit of any matched string, for a
1218  non-anchored pattern. The fourth argument should point to an \fBint\fP  non-anchored pattern. (The name of this option refers to the 8-bit library,
1219  variable. (This option used to be called PCRE_INFO_FIRSTCHAR; the old name is  where data units are bytes.) The fourth argument should point to an \fBint\fP
1220  still recognized for backwards compatibility.)  variable.
1221    .P
1222    If there is a fixed first value, for example, the letter "c" from a pattern
1223    such as (cat|cow|coyote), its value is returned. In the 8-bit library, the
1224    value is always less than 256. In the 16-bit library the value can be up to
1225    0xffff. In the 32-bit library the value can be up to 0x10ffff.
1226  .P  .P
1227  If there is a fixed first byte, for example, from a pattern such as  If there is no fixed first value, and if either
 (cat|cow|coyote), its value is returned. Otherwise, if either  
1228  .sp  .sp
1229  (a) the pattern was compiled with the PCRE_MULTILINE option, and every branch  (a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
1230  starts with "^", or  starts with "^", or
# Line 1114  starts with "^", or Line 1235  starts with "^", or
1235  -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
1236  subject string or after any newline within the string. Otherwise -2 is  subject string or after any newline within the string. Otherwise -2 is
1237  returned. For anchored patterns, -2 is returned.  returned. For anchored patterns, -2 is returned.
1238    .P
1239    Since for the 32-bit library using the non-UTF-32 mode, this function is unable
1240    to return the full 32-bit range of the character, this value is deprecated;
1241    instead the PCRE_INFO_FIRSTCHARACTERFLAGS and PCRE_INFO_FIRSTCHARACTER values should
1242    be used.
1243  .sp  .sp
1244    PCRE_INFO_FIRSTTABLE    PCRE_INFO_FIRSTTABLE
1245  .sp  .sp
1246  If the pattern was studied, and this resulted in the construction of a 256-bit  If the pattern was studied, and this resulted in the construction of a 256-bit
1247  table indicating a fixed set of bytes for the first byte in any matching  table indicating a fixed set of values for the first data unit in any matching
1248  string, a pointer to the table is returned. Otherwise NULL is returned. The  string, a pointer to the table is returned. Otherwise NULL is returned. The
1249  fourth argument should point to an \fBunsigned char *\fP variable.  fourth argument should point to an \fBunsigned char *\fP variable.
1250  .sp  .sp
# Line 1136  Return 1 if the (?J) or (?-J) option set Line 1262  Return 1 if the (?J) or (?-J) option set
1262  .sp  .sp
1263    PCRE_INFO_JIT    PCRE_INFO_JIT
1264  .sp  .sp
1265  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
1266  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
1267  \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
1268  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,
1269  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  
1270  .\" HREF  .\" HREF
1271  \fBpcrejit\fP  \fBpcrejit\fP
1272  .\"  .\"
# Line 1149  documentation for details of what can an Line 1274  documentation for details of what can an
1274  .sp  .sp
1275    PCRE_INFO_JITSIZE    PCRE_INFO_JITSIZE
1276  .sp  .sp
1277  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
1278  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
1279  argument should point to a \fBsize_t\fP variable.  to a \fBsize_t\fP variable.
1280  .sp  .sp
1281    PCRE_INFO_LASTLITERAL    PCRE_INFO_LASTLITERAL
1282  .sp  .sp
1283  Return the value of the rightmost literal byte that must exist in any matched  Return the value of the rightmost literal data unit that must exist in any
1284  string, other than at its start, if such a byte has been recorded. The fourth  matched string, other than at its start, if such a value has been recorded. The
1285  argument should point to an \fBint\fP variable. If there is no such byte, -1 is  fourth argument should point to an \fBint\fP variable. If there is no such
1286  returned. For anchored patterns, a last literal byte is recorded only if it  value, -1 is returned. For anchored patterns, a last literal value is recorded
1287  follows something of variable length. For example, for the pattern  only if it follows something of variable length. For example, for the pattern
1288  /^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
1289  is -1.  is -1.
1290    .P
1291    Since for the 32-bit library using the non-UTF-32 mode, this function is unable
1292    to return the full 32-bit range of the character, this value is deprecated;
1293    instead the PCRE_INFO_REQUIREDCHARFLAGS and PCRE_INFO_REQUIREDCHAR values should
1294    be used.
1295    .sp
1296      PCRE_INFO_MAXLOOKBEHIND
1297    .sp
1298    Return the number of characters (NB not bytes) in the longest lookbehind
1299    assertion in the pattern. Note that the simple assertions \eb and \eB require a
1300    one-character lookbehind. This information is useful when doing multi-segment
1301    matching using the partial matching facilities.
1302  .sp  .sp
1303    PCRE_INFO_MINLENGTH    PCRE_INFO_MINLENGTH
1304  .sp  .sp
1305  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
1306  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
1307  value is a number of characters, not bytes (this may be relevant in UTF-8  value is a number of characters, which in UTF-8 mode may be different from the
1308  mode). The fourth argument should point to an \fBint\fP variable. A  number of bytes. The fourth argument should point to an \fBint\fP variable. A
1309  non-negative value is a lower bound to the length of any matching string. There  non-negative value is a lower bound to the length of any matching string. There
1310  may not be any strings of that length that do actually match, but every string  may not be any strings of that length that do actually match, but every string
1311  that does match is at least that long.  that does match is at least that long.
# Line 1191  The map consists of a number of fixed-si Line 1328  The map consists of a number of fixed-si
1328  the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size of each  the number of entries, and PCRE_INFO_NAMEENTRYSIZE gives the size of each
1329  entry; both of these return an \fBint\fP value. The entry size depends on the  entry; both of these return an \fBint\fP value. The entry size depends on the
1330  length of the longest name. PCRE_INFO_NAMETABLE returns a pointer to the first  length of the longest name. PCRE_INFO_NAMETABLE returns a pointer to the first
1331  entry of the table (a pointer to \fBchar\fP). The first two bytes of each entry  entry of the table. This is a pointer to \fBchar\fP in the 8-bit library, where
1332  are the number of the capturing parenthesis, most significant byte first. The  the first two bytes of each entry are the number of the capturing parenthesis,
1333  rest of the entry is the corresponding name, zero terminated.  most significant byte first. In the 16-bit library, the pointer points to
1334    16-bit data units, the first of which contains the parenthesis number.
1335    In the 32-bit library, the pointer points to 32-bit data units, the first of
1336    which contains the parenthesis number. The rest
1337    of the entry is the corresponding name, zero terminated.
1338  .P  .P
1339  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
1340  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 1212  table in the order in which they were fo Line 1353  table in the order in which they were fo
1353  necessarily the case because later subpatterns may have lower numbers.  necessarily the case because later subpatterns may have lower numbers.
1354  .P  .P
1355  As a simple example of the name/number table, consider the following pattern  As a simple example of the name/number table, consider the following pattern
1356  (assume PCRE_EXTENDED is set, so white space - including newlines - is  after compilation by the 8-bit library (assume PCRE_EXTENDED is set, so white
1357  ignored):  space - including newlines - is ignored):
1358  .sp  .sp
1359  .\" JOIN  .\" JOIN
1360    (?<date> (?<year>(\ed\ed)?\ed\ed) -    (?<date> (?<year>(\ed\ed)?\ed\ed) -
# Line 1268  For such patterns, the PCRE_ANCHORED bit Line 1409  For such patterns, the PCRE_ANCHORED bit
1409  .sp  .sp
1410    PCRE_INFO_SIZE    PCRE_INFO_SIZE
1411  .sp  .sp
1412  Return the size of the compiled pattern. The fourth argument should point to a  Return the size of the compiled pattern in bytes (for both libraries). The
1413  \fBsize_t\fP variable. This value does not include the size of the \fBpcre\fP  fourth argument should point to a \fBsize_t\fP variable. This value does not
1414  structure that is returned by \fBpcre_compile()\fP. The value that is passed as  include the size of the \fBpcre\fP structure that is returned by
1415  the argument to \fBpcre_malloc()\fP when \fBpcre_compile()\fP is getting memory  \fBpcre_compile()\fP. The value that is passed as the argument to
1416  in which to place the compiled data is the value returned by this option plus  \fBpcre_malloc()\fP when \fBpcre_compile()\fP is getting memory in which to
1417  the size of the \fBpcre\fP structure. Studying a compiled pattern, with or  place the compiled data is the value returned by this option plus the size of
1418  without JIT, does not alter the value returned by this option.  the \fBpcre\fP structure. Studying a compiled pattern, with or without JIT,
1419    does not alter the value returned by this option.
1420  .sp  .sp
1421    PCRE_INFO_STUDYSIZE    PCRE_INFO_STUDYSIZE
1422  .sp  .sp
1423  Return the size of the data block pointed to by the \fIstudy_data\fP field in a  Return the size in bytes of the data block pointed to by the \fIstudy_data\fP
1424  \fBpcre_extra\fP block. If \fBpcre_extra\fP is NULL, or there is no study data,  field in a \fBpcre_extra\fP block. If \fBpcre_extra\fP is NULL, or there is no
1425  zero is returned. The fourth argument should point to a \fBsize_t\fP variable.  study data, zero is returned. The fourth argument should point to a
1426  The \fIstudy_data\fP field is set by \fBpcre_study()\fP to record information  \fBsize_t\fP variable. The \fIstudy_data\fP field is set by \fBpcre_study()\fP
1427  that will speed up matching (see the section entitled  to record information that will speed up matching (see the section entitled
1428  .\" HTML <a href="#studyingapattern">  .\" HTML <a href="#studyingapattern">
1429  .\" </a>  .\" </a>
1430  "Studying a pattern"  "Studying a pattern"
# Line 1293  is made available via this option so tha Line 1435  is made available via this option so tha
1435  \fBpcreprecompile\fP  \fBpcreprecompile\fP
1436  .\"  .\"
1437  documentation for details).  documentation for details).
 .  
 .  
 .SH "OBSOLETE INFO FUNCTION"  
 .rs  
1438  .sp  .sp
1439  .B int pcre_info(const pcre *\fIcode\fP, int *\fIoptptr\fP, int    PCRE_INFO_FIRSTCHARACTERFLAGS
1440  .B *\fIfirstcharptr\fP);  .sp
1441  .PP  Return information about the first data unit of any matched string, for a
1442  The \fBpcre_info()\fP function is now obsolete because its interface is too  non-anchored pattern. The fourth argument should point to an \fBint\fP
1443  restrictive to return all the available data about a compiled pattern. New  variable.
1444  programs should use \fBpcre_fullinfo()\fP instead. The yield of  .P
1445  \fBpcre_info()\fP is the number of capturing subpatterns, or one of the  If there is a fixed first value, for example, the letter "c" from a pattern
1446  following negative numbers:  such as (cat|cow|coyote), 1 is returned, and the character value can be
1447    retrieved using PCRE_INFO_FIRSTCHARACTER.
1448    .P
1449    If there is no fixed first value, and if either
1450  .sp  .sp
1451    PCRE_ERROR_NULL       the argument \fIcode\fP was NULL  (a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
1452    PCRE_ERROR_BADMAGIC   the "magic number" was not found  starts with "^", or
1453    .sp
1454    (b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
1455    (if it were set, the pattern would be anchored),
1456    .sp
1457    2 is returned, indicating that the pattern matches only at the start of a
1458    subject string or after any newline within the string. Otherwise 0 is
1459    returned. For anchored patterns, 0 is returned.
1460  .sp  .sp
1461  If the \fIoptptr\fP argument is not NULL, a copy of the options with which the    PCRE_INFO_FIRSTCHARACTER
1462  pattern was compiled is placed in the integer it points to (see  .sp
1463  PCRE_INFO_OPTIONS above).  Return the fixed first character value, if PCRE_INFO_FIRSTCHARACTERFLAGS returned 1;
1464    otherwise returns 0. The fourth argument should point to an \fBuint_t\fP
1465    variable.
1466    .P
1467    In the 8-bit library, the value is always less than 256. In the 16-bit library
1468    the value can be up to 0xffff. In the 32-bit library in UTF-32 mode the value
1469    can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32 mode.
1470  .P  .P
1471  If the pattern is not anchored and the \fIfirstcharptr\fP argument is not NULL,  If there is no fixed first value, and if either
1472  it is used to pass back information about the first character of any matched  .sp
1473  string (see PCRE_INFO_FIRSTBYTE above).  (a) the pattern was compiled with the PCRE_MULTILINE option, and every branch
1474    starts with "^", or
1475    .sp
1476    (b) every branch of the pattern starts with ".*" and PCRE_DOTALL is not set
1477    (if it were set, the pattern would be anchored),
1478    .sp
1479    -1 is returned, indicating that the pattern matches only at the start of a
1480    subject string or after any newline within the string. Otherwise -2 is
1481    returned. For anchored patterns, -2 is returned.
1482    .sp
1483      PCRE_INFO_REQUIREDCHARFLAGS
1484    .sp
1485    Returns 1 if there is a rightmost literal data unit that must exist in any matched
1486    string, other than at its start. The fourth argument should  point to an \fBint\fP
1487    variable. If there is no such value, 0 is returned. If returning 1, the character
1488    value itself can be retrieved using PCRE_INFO_REQUIREDCHAR.
1489    .P
1490    For anchored patterns, a last literal value is recorded only if it follows something
1491    of variable length. For example, for the pattern /^a\ed+z\ed+/ the returned value
1492    1 (with "z" returned from PCRE_INFO_REQUIREDCHAR), but for /^a\edz\ed/ the returned
1493    value is 0.
1494    .sp
1495      PCRE_INFO_REQUIREDCHAR
1496    .sp
1497    Return the value of the rightmost literal data unit that must exist in any
1498    matched string, other than at its start, if such a value has been recorded. The
1499    fourth argument should point to an \fBuint32_t\fP variable. If there is no such
1500    value, 0 is returned.
1501  .  .
1502  .  .
1503  .SH "REFERENCE COUNTS"  .SH "REFERENCE COUNTS"
# Line 1411  fields (not necessarily in this order): Line 1592  fields (not necessarily in this order):
1592    const unsigned char *\fItables\fP;    const unsigned char *\fItables\fP;
1593    unsigned char **\fImark\fP;    unsigned char **\fImark\fP;
1594  .sp  .sp
1595  The \fIflags\fP field is a bitmap that specifies which of the other fields  In the 16-bit version of this structure, the \fImark\fP field has type
1596  are set. The flag bits are:  "PCRE_UCHAR16 **".
1597  .sp  .sp
1598    PCRE_EXTRA_STUDY_DATA  In the 32-bit version of this structure, the \fImark\fP field has type
1599    "PCRE_UCHAR32 **".
1600    .P
1601    The \fIflags\fP field is used to specify which of the other fields are set. The
1602    flag bits are:
1603    .sp
1604      PCRE_EXTRA_CALLOUT_DATA
1605    PCRE_EXTRA_EXECUTABLE_JIT    PCRE_EXTRA_EXECUTABLE_JIT
1606      PCRE_EXTRA_MARK
1607    PCRE_EXTRA_MATCH_LIMIT    PCRE_EXTRA_MATCH_LIMIT
1608    PCRE_EXTRA_MATCH_LIMIT_RECURSION    PCRE_EXTRA_MATCH_LIMIT_RECURSION
1609    PCRE_EXTRA_CALLOUT_DATA    PCRE_EXTRA_STUDY_DATA
1610    PCRE_EXTRA_TABLES    PCRE_EXTRA_TABLES
   PCRE_EXTRA_MARK  
1611  .sp  .sp
1612  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
1613  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
1614  returned by \fBpcre_study()\fP, together with the appropriate flag bits. You  returned by \fBpcre_study()\fP, together with the appropriate flag bits. You
1615  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
1616  other fields and their corresponding flag bits.  fields and their corresponding flag bits.
1617  .P  .P
1618  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
1619  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 1441  patterns that are not anchored, the coun Line 1628  patterns that are not anchored, the coun
1628  in the subject string.  in the subject string.
1629  .P  .P
1630  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
1631  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.
1632  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
1633  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
1634  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.  
1635  .P  .P
1636  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
1637  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 1463  This limit is of use only if it is set s Line 1649  This limit is of use only if it is set s
1649  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
1650  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
1651  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,
1652  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.  
1653  .P  .P
1654  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
1655  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 1495  called. See the Line 1680  called. See the
1680  documentation for a discussion of saving compiled patterns for later use.  documentation for a discussion of saving compiled patterns for later use.
1681  .P  .P
1682  If PCRE_EXTRA_MARK is set in the \fIflags\fP field, the \fImark\fP field must  If PCRE_EXTRA_MARK is set in the \fIflags\fP field, the \fImark\fP field must
1683  be set to point to a \fBchar *\fP variable. If the pattern contains any  be set to point to a suitable variable. If the pattern contains any
1684  backtracking control verbs such as (*MARK:NAME), and the execution ends up with  backtracking control verbs such as (*MARK:NAME), and the execution ends up with
1685  a name to pass back, a pointer to the name string (zero terminated) is placed  a name to pass back, a pointer to the name string (zero terminated) is placed
1686  in the variable pointed to by the \fImark\fP field. The names are within the  in the variable pointed to by the \fImark\fP field. The names are within the
1687  compiled pattern; if you wish to retain such a name you must copy it before  compiled pattern; if you wish to retain such a name you must copy it before
1688  freeing the memory of a compiled pattern. If there is no name to pass back, the  freeing the memory of a compiled pattern. If there is no name to pass back, the
1689  variable pointed to by the \fImark\fP field set to NULL. For details of the  variable pointed to by the \fImark\fP field is set to NULL. For details of the
1690  backtracking control verbs, see the section entitled  backtracking control verbs, see the section entitled
1691  .\" HTML <a href="pcrepattern#backtrackcontrol">  .\" HTML <a href="pcrepattern#backtrackcontrol">
1692  .\" </a>  .\" </a>
# Line 1521  documentation. Line 1706  documentation.
1706  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
1707  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,
1708  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, PCRE_NOTEMPTY_ATSTART,
1709  PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_SOFT, and  PCRE_NO_START_OPTIMIZE, PCRE_NO_UTF8_CHECK, PCRE_PARTIAL_HARD, and
1710  PCRE_PARTIAL_HARD.  PCRE_PARTIAL_SOFT.
1711  .P  .P
1712  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)
1713  the only supported options for JIT execution are PCRE_NO_UTF8_CHECK,  compile options, the only supported options for JIT execution are
1714  PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY, and PCRE_NOTEMPTY_ATSTART. Note in  PCRE_NO_UTF8_CHECK, PCRE_NOTBOL, PCRE_NOTEOL, PCRE_NOTEMPTY,
1715  particular that partial matching is not supported. If an unsupported option is  PCRE_NOTEMPTY_ATSTART, PCRE_PARTIAL_HARD, and PCRE_PARTIAL_SOFT. If an
1716  used, JIT execution is disabled and the normal interpretive code in  unsupported option is used, JIT execution is disabled and the normal
1717  \fBpcre_exec()\fP is run.  interpretive code in \fBpcre_exec()\fP is run.
1718  .sp  .sp
1719    PCRE_ANCHORED    PCRE_ANCHORED
1720  .sp  .sp
# Line 1648  causing performance to suffer, but ensur Line 1833  causing performance to suffer, but ensur
1833  "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)
1834  are considered at every possible starting position in the subject string. If  are considered at every possible starting position in the subject string. If
1835  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
1836  time.  time. The use of PCRE_NO_START_OPTIMIZE disables JIT execution; when it is set,
1837    matching is always done using interpretively.
1838  .P  .P
1839  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.
1840  Consider the pattern  Consider the pattern
# Line 1681  returned. Line 1867  returned.
1867  .sp  .sp
1868  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
1869  string is automatically checked when \fBpcre_exec()\fP is subsequently called.  string is automatically checked when \fBpcre_exec()\fP is subsequently called.
1870  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
1871  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
1872  strings in the  UTF-8 character. There is a discussion about the
1873  .\" HTML <a href="pcre.html#utf8strings">  .\" HTML <a href="pcreunicode.html#utf8strings">
1874  .\" </a>  .\" </a>
1875  section on UTF-8 support  validity of UTF-8 strings
1876  .\"  .\"
1877  in the main  in the
1878  .\" HREF  .\" HREF
1879  \fBpcre\fP  \fBpcreunicode\fP
1880  .\"  .\"
1881  page. If an invalid UTF-8 sequence of bytes is found, \fBpcre_exec()\fP returns  page. If an invalid sequence of bytes is found, \fBpcre_exec()\fP returns the
1882  the error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is  error PCRE_ERROR_BADUTF8 or, if PCRE_PARTIAL_HARD is set and the problem is a
1883  a truncated UTF-8 character at the end of the subject, PCRE_ERROR_SHORTUTF8. In  truncated character at the end of the subject, PCRE_ERROR_SHORTUTF8. In both
1884  both cases, information about the precise nature of the error may also be  cases, information about the precise nature of the error may also be returned
1885  returned (see the descriptions of these errors in the section entitled \fIError  (see the descriptions of these errors in the section entitled \fIError return
1886  return values from\fP \fBpcre_exec()\fP  values from\fP \fBpcre_exec()\fP
1887  .\" HTML <a href="#errorlist">  .\" HTML <a href="#errorlist">
1888  .\" </a>  .\" </a>
1889  below).  below).
# Line 1711  checks for performance reasons, you can Line 1897  checks for performance reasons, you can
1897  calling \fBpcre_exec()\fP. You might want to do this for the second and  calling \fBpcre_exec()\fP. You might want to do this for the second and
1898  subsequent calls to \fBpcre_exec()\fP if you are making repeated calls to find  subsequent calls to \fBpcre_exec()\fP if you are making repeated calls to find
1899  all the matches in a single subject string. However, you should be sure that  all the matches in a single subject string. However, you should be sure that
1900  the value of \fIstartoffset\fP points to the start of a UTF-8 character (or the  the value of \fIstartoffset\fP points to the start of a character (or the end
1901  end of the subject). When PCRE_NO_UTF8_CHECK is set, the effect of passing an  of the subject). When PCRE_NO_UTF8_CHECK is set, the effect of passing an
1902  invalid UTF-8 string as a subject or an invalid value of \fIstartoffset\fP is  invalid string as a subject or an invalid value of \fIstartoffset\fP is
1903  undefined. Your program may crash.  undefined. Your program may crash.
1904  .sp  .sp
1905    PCRE_PARTIAL_HARD    PCRE_PARTIAL_HARD
# Line 1748  documentation. Line 1934  documentation.
1934  .rs  .rs
1935  .sp  .sp
1936  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
1937  \fIsubject\fP, a length (in bytes) in \fIlength\fP, and a starting byte offset  \fIsubject\fP, a length in bytes in \fIlength\fP, and a starting byte offset
1938  in \fIstartoffset\fP. If this is negative or greater than the length of the  in \fIstartoffset\fP. If this is negative or greater than the length of the
1939  subject, \fBpcre_exec()\fP returns PCRE_ERROR_BADOFFSET. When the starting  subject, \fBpcre_exec()\fP returns PCRE_ERROR_BADOFFSET. When the starting
1940  offset is zero, the search for a match starts at the beginning of the subject,  offset is zero, the search for a match starts at the beginning of the subject,
# Line 1836  string that it matched that is returned. Line 2022  string that it matched that is returned.
2022  .P  .P
2023  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
2024  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
2025  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
2026  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
2027  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
2028  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 2036  time. Line 2222  time.
2222  .sp  .sp
2223    PCRE_ERROR_JIT_STACKLIMIT (-27)    PCRE_ERROR_JIT_STACKLIMIT (-27)
2224  .sp  .sp
2225  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
2226  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
2227  the just-in-time processing stack is not large enough. See the  just-in-time processing stack is not large enough. See the
2228  .\" HREF  .\" HREF
2229  \fBpcrejit\fP  \fBpcrejit\fP
2230  .\"  .\"
2231  documentation for more details.  documentation for more details.
2232    .sp
2233      PCRE_ERROR_BADMODE        (-28)
2234    .sp
2235    This error is given if a pattern that was compiled by the 8-bit library is
2236    passed to a 16-bit or 32-bit library function, or vice versa.
2237    .sp
2238      PCRE_ERROR_BADENDIANNESS  (-29)
2239    .sp
2240    This error is given if a pattern that was compiled and saved is reloaded on a
2241    host with different endianness. The utility function
2242    \fBpcre_pattern_to_host_byte_order()\fP can be used to convert such a pattern
2243    so that it runs on the new host.
2244  .P  .P
2245  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.
2246  .  .
2247  .  .
2248  .\" HTML <a name="badutf8reasons"></a>  .\" HTML <a name="badutf8reasons"></a>
2249  .SS "Reason codes for invalid UTF-8 strings"  .SS "Reason codes for invalid UTF-8 strings"
2250  .rs  .rs
2251  .sp  .sp
2252    This section applies only to the 8-bit library. The corresponding information
2253    for the 16-bit library is given in the
2254    .\" HREF
2255    \fBpcre16\fP
2256    .\"
2257    page. The corresponding information for the 32-bit library is given in the
2258    .\" HREF
2259    \fBpcre32\fP
2260    .\"
2261    page.
2262    .P
2263  When \fBpcre_exec()\fP returns either PCRE_ERROR_BADUTF8 or  When \fBpcre_exec()\fP returns either PCRE_ERROR_BADUTF8 or
2264  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
2265  least 2, the offset of the start of the invalid UTF-8 character is placed in  least 2, the offset of the start of the invalid UTF-8 character is placed in
# Line 2119  character. Line 2328  character.
2328  .sp  .sp
2329  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
2330  never occur in a valid UTF-8 string.  never occur in a valid UTF-8 string.
2331    .sp
2332      PCRE_UTF8_ERR2
2333    .sp
2334    Non-character. These are the last two characters in each plane (0xfffe, 0xffff,
2335    0x1fffe, 0x1ffff .. 0x10fffe, 0x10ffff), and the characters 0xfdd0..0xfdef.
2336  .  .
2337  .  .
2338  .SH "EXTRACTING CAPTURED SUBSTRINGS BY NUMBER"  .SH "EXTRACTING CAPTURED SUBSTRINGS BY NUMBER"
# Line 2348  other alternatives. Ultimately, when it Line 2562  other alternatives. Ultimately, when it
2562  will yield PCRE_ERROR_NOMATCH.  will yield PCRE_ERROR_NOMATCH.
2563  .  .
2564  .  .
2565    .SH "OBTAINING AN ESTIMATE OF STACK USAGE"
2566    .rs
2567    .sp
2568    Matching certain patterns using \fBpcre_exec()\fP can use a lot of process
2569    stack, which in certain environments can be rather limited in size. Some users
2570    find it helpful to have an estimate of the amount of stack that is used by
2571    \fBpcre_exec()\fP, to help them set recursion limits, as described in the
2572    .\" HREF
2573    \fBpcrestack\fP
2574    .\"
2575    documentation. The estimate that is output by \fBpcretest\fP when called with
2576    the \fB-m\fP and \fB-C\fP options is obtained by calling \fBpcre_exec\fP with
2577    the values NULL, NULL, NULL, -999, and -999 for its first five arguments.
2578    .P
2579    Normally, if its first argument is NULL, \fBpcre_exec()\fP immediately returns
2580    the negative error code PCRE_ERROR_NULL, but with this special combination of
2581    arguments, it returns instead a negative number whose absolute value is the
2582    approximate stack frame size in bytes. (A negative number is used so that it is
2583    clear that no match has happened.) The value is approximate because in some
2584    cases, recursive calls to \fBpcre_exec()\fP occur when there are one or two
2585    additional variables on the stack.
2586    .P
2587    If PCRE has been compiled to use the heap instead of the stack for recursion,
2588    the value returned is the size of each block that is obtained from the heap.
2589    .
2590    .
2591  .\" HTML <a name="dfamatch"></a>  .\" HTML <a name="dfamatch"></a>
2592  .SH "MATCHING A PATTERN: THE ALTERNATIVE FUNCTION"  .SH "MATCHING A PATTERN: THE ALTERNATIVE FUNCTION"
2593  .rs  .rs
# Line 2529  When a recursive subpattern is processed Line 2769  When a recursive subpattern is processed
2769  recursively, using private vectors for \fIovector\fP and \fIworkspace\fP. This  recursively, using private vectors for \fIovector\fP and \fIworkspace\fP. This
2770  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
2771  extremely rare, as a vector of size 1000 is used.  extremely rare, as a vector of size 1000 is used.
2772    .sp
2773      PCRE_ERROR_DFA_BADRESTART (-30)
2774    .sp
2775    When \fBpcre_dfa_exec()\fP is called with the \fBPCRE_DFA_RESTART\fP option,
2776    some plausibility checks are made on the contents of the workspace, which
2777    should contain data about the previous partial match. If any of these checks
2778    fail, this error is given.
2779  .  .
2780  .  .
2781  .SH "SEE ALSO"  .SH "SEE ALSO"
2782  .rs  .rs
2783  .sp  .sp
2784  \fBpcrebuild\fP(3), \fBpcrecallout\fP(3), \fBpcrecpp(3)\fP(3),  \fBpcre16\fP(3), \fBpcre32\fP(3), \fBpcrebuild\fP(3), \fBpcrecallout\fP(3),
2785  \fBpcrematching\fP(3), \fBpcrepartial\fP(3), \fBpcreposix\fP(3),  \fBpcrecpp(3)\fP(3), \fBpcrematching\fP(3), \fBpcrepartial\fP(3),
2786  \fBpcreprecompile\fP(3), \fBpcresample\fP(3), \fBpcrestack\fP(3).  \fBpcreposix\fP(3), \fBpcreprecompile\fP(3), \fBpcresample\fP(3),
2787    \fBpcrestack\fP(3).
2788  .  .
2789  .  .
2790  .SH AUTHOR  .SH AUTHOR
# Line 2553  Cambridge CB2 3QH, England. Line 2801  Cambridge CB2 3QH, England.
2801  .rs  .rs
2802  .sp  .sp
2803  .nf  .nf
2804  Last updated: 02 December 2011  Last updated: 07 September 2012
2805  Copyright (c) 1997-2011 University of Cambridge.  Copyright (c) 1997-2012 University of Cambridge.
2806  .fi  .fi

Legend:
Removed from v.788  
changed lines
  Added in v.1113

  ViewVC Help
Powered by ViewVC 1.1.5