Synopsis

#include <pcre2.h>

int pcre2_callout_enumerate(
      const pcre2_code *code,
      int (*callback)(pcre2_callout_enumerate_block *callout_block,
                      void *callout_data),
      void *callout_data);

Description

This function scans a compiled regular expression and calls the callback() function for each callout within the pattern. The yield of the function is zero for success and non-zero otherwise. The arguments are:

code

Points to the compiled pattern

callback

The callback function

callout_data

User data that is passed to the callback

The callback() function is passed a pointer to a data block containing the following fields (not necessarily in this order):

uint32_t version

Block version number

uint32_t callout_number

Number for numbered callouts

PCRE2_SIZE pattern_position

Offset to next item in pattern

PCRE2_SIZE next_item_length

Length of next item in pattern

PCRE2_SIZE callout_string_offset

Offset to string within pattern

PCRE2_SIZE callout_string_length

Length of callout string

PCRE2_SPTR callout_string

Points to callout string or is NULL

The second argument passed to the callback() function is the callout data that was passed to pcre2_callout_enumerate(). The callback() function must return zero for success. Any other value causes the pattern scan to stop, with the value being passed back as the result of pcre2_callout_enumerate().

There is a complete description of the PCRE2 native API in the pcre2api page and a description of the POSIX API in the pcre2posix page.