int pcre_get_named_substring(const pcre *code, const char *subject, int *ovector, int stringcount, const char *stringname, const char **stringptr);
This is a convenience function for extracting a captured substring by name. The arguments are:
code Compiled pattern subject Subject that has been successfully matched ovector Offset vector that pcre_exec() used stringcount Value returned by pcre_exec() stringname Name of the required substring stringptr Where to put the string pointer
The yield is the length of the extracted substring, PCRE_ERROR_NOMEMORY if sufficient memory could not be obtained, or PCRE_ERROR_NOSUBSTRING if the string name is invalid.
There is a complete description of the PCRE API in the pcreapi page.