Section: C Library Functions (3)
Updated: 05 November 2013
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PCRE - Perl-compatible regular expressions  


#include <pcre.h>

int pcre_config(int what, void *where);

int pcre16_config(int what, void *where);

int pcre32_config(int what, void *where);  


This function makes it possible for a client program to find out which optional features are available in the version of the PCRE library it is using. The arguments are as follows:

  what     A code specifying what information is required
  where    Points to where to put the data

The where argument must point to an integer variable, except for PCRE_CONFIG_MATCH_LIMIT and PCRE_CONFIG_MATCH_LIMIT_RECURSION, when it must point to an unsigned long integer. The available codes are:

  PCRE_CONFIG_JIT           Availability of just-in-time compiler
                              support (1=yes 0=no)
  PCRE_CONFIG_JITTARGET     String containing information about the
                              target architecture for the JIT compiler,
                              or NULL if there is no JIT support
  PCRE_CONFIG_LINK_SIZE     Internal link size: 2, 3, or 4
  PCRE_CONFIG_PARENS_LIMIT  Parentheses nesting limit
  PCRE_CONFIG_MATCH_LIMIT   Internal resource limit
                            Internal recursion depth limit
  PCRE_CONFIG_NEWLINE       Value of the default newline sequence:
                                13 (0x000d)    for CR
                                10 (0x000a)    for LF
                              3338 (0x0d0a)    for CRLF
                                -2             for ANYCRLF
                                -1             for ANY
  PCRE_CONFIG_BSR           Indicates what \R matches by default:
                                 0             all Unicode line endings
                                 1             CR, LF, or CRLF only
                            Threshold of return slots, above which
                              malloc() is used by the POSIX API
  PCRE_CONFIG_STACKRECURSE  Recursion implementation (1=stack 0=heap)
  PCRE_CONFIG_UTF16         Availability of UTF-16 support (1=yes
                               0=no); option for pcre16_config()
  PCRE_CONFIG_UTF32         Availability of UTF-32 support (1=yes
                               0=no); option for pcre32_config()
  PCRE_CONFIG_UTF8          Availability of UTF-8 support (1=yes 0=no);
                              option for pcre_config()
                            Availability of Unicode property support
                              (1=yes 0=no)

The function yields 0 on success or PCRE_ERROR_BADOPTION otherwise. That error is also given if PCRE_CONFIG_UTF16 or PCRE_CONFIG_UTF32 is passed to pcre_config(), if PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF32 is passed to pcre16_config(), or if PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF16 is passed to pcre32_config().

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.