Function regerror
pub unsafe extern "C" fn regerror(errcode: c_int, preg: *const regex_t, errbuf: *mut c_char, errbuf_size: size_t) -> size_tregerrorpub unsafe extern "C" fn regerror(errcode: c_int, preg: *const regex_t, errbuf: *mut c_char, errbuf_size: size_t) -> size_t