NAME

PCRE - Perl-compatible regular expressions

SYNOPSIS

#include <pcre.h>

int pcre_fullinfo(const pcre *code, const pcre_extra *extra,
     int what, void *where);

int pcre16_fullinfo(const pcre16 *code, const pcre16_extra *extra,
     int what, void *where);

int pcre32_fullinfo(const pcre32 *code, const pcre32_extra *extra,
     int what, void *where);

DESCRIPTION

This function returns information about a compiled pattern. Its arguments are:

code Compiled regular expression
extra Result of pcre[16|32]_study() or NULL
what What information is required
where Where to put the information

The following information is available:

PCRE_INFO_BACKREFMAX Number of highest back reference
PCRE_INFO_CAPTURECOUNT Number of capturing subpatterns
PCRE_INFO_DEFAULT_TABLES Pointer to default tables
PCRE_INFO_FIRSTBYTE Fixed first data unit for a match, or
-1 for start of string
or after newline, or
-2 otherwise
PCRE_INFO_FIRSTTABLE Table of first data units (after studying)
PCRE_INFO_HASCRORLF Return 1 if explicit CR or LF matches exist
PCRE_INFO_JCHANGED Return 1 if (?J) or (?-J) was used
PCRE_INFO_JIT Return 1 after successful JIT compilation
PCRE_INFO_JITSIZE Size of JIT compiled code
PCRE_INFO_LASTLITERAL Literal last data unit required
PCRE_INFO_MINLENGTH Lower bound length of matching strings
PCRE_INFO_MATCHEMPTY Return 1 if the pattern can match an empty string,
0 otherwise
PCRE_INFO_MATCHLIMIT Match limit if set, otherwise PCRE_RROR_UNSET
PCRE_INFO_MAXLOOKBEHIND Length (in characters) of the longest lookbehind assertion
PCRE_INFO_NAMECOUNT Number of named subpatterns
PCRE_INFO_NAMEENTRYSIZE Size of name table entry
PCRE_INFO_NAMETABLE Pointer to name table
PCRE_INFO_OKPARTIAL Return 1 if partial matching can be tried
(always returns 1 after release 8.00)
PCRE_INFO_OPTIONS Option bits used for compilation
PCRE_INFO_SIZE Size of compiled pattern
PCRE_INFO_STUDYSIZE Size of study data
PCRE_INFO_FIRSTCHARACTER Fixed first data unit for a match
PCRE_INFO_FIRSTCHARACTERFLAGS Returns
1 if there is a first data character set, which can
then be retrieved using PCRE_INFO_FIRSTCHARACTER,
2 if the first character is at the start of the data
string or after a newline, and
0 otherwise
PCRE_INFO_RECURSIONLIMIT Recursion limit if set, otherwise PCRE_ERROR_UNSET
PCRE_INFO_REQUIREDCHAR Literal last data unit required
PCRE_INFO_REQUIREDCHARFLAGS Returns 1 if the last data character is set (which can then
be retrieved using PCRE_INFO_REQUIREDCHAR); 0 otherwise

The where argument must point to an integer variable, except for the following what values:

PCRE_INFO_DEFAULT_TABLES const uint8_t *
PCRE_INFO_FIRSTCHARACTER uint32_t
PCRE_INFO_FIRSTTABLE const uint8_t *
PCRE_INFO_JITSIZE size_t
PCRE_INFO_MATCHLIMIT uint32_t
PCRE_INFO_NAMETABLE PCRE_SPTR16 (16-bit library)
PCRE_INFO_NAMETABLE PCRE_SPTR32 (32-bit library)
PCRE_INFO_NAMETABLE const unsigned char * (8-bit library)
PCRE_INFO_OPTIONS unsigned long int
PCRE_INFO_SIZE size_t
PCRE_INFO_STUDYSIZE size_t
PCRE_INFO_RECURSIONLIMIT uint32_t
PCRE_INFO_REQUIREDCHAR uint32_t

The yield of the function is zero on success or:

PCRE_ERROR_NULL the argument code was NULL
the argument where was NULL
PCRE_ERROR_BADMAGIC the "magic number" was not found
PCRE_ERROR_BADOPTION the value of what was invalid
PCRE_ERROR_UNSET the option was not set

There is a complete description of the PCRE native API in the pcreapi page and a description of the POSIX API in the pcreposix page.