# pcre2_callout_enumerate man page

Return to the PCRE2 index page.

This page is part of the PCRE2 HTML documentation. It was generated automatically from the original man page. If there is any nonsense in it, please consult the man page, in case the conversion went wrong.
SYNOPSIS

#include <pcre2.h>

int pcre2_callout_enumerate(const pcre2_code *code, int (*callback)(pcre2_callout_enumerate_block *, void *), 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.

Return to the PCRE2 index page.