#include <pcre.h>
void pcre_free_substring_list(const char **stringptr);
This is a convenience function for freeing the store obtained by a previous call to pcre_get_substring_list(). Its only argument is a pointer to the list of string pointers.
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.