@item @var{int} @ref{gnutls_certificate_set_openpgp_key_mem2} (gnutls_certificate_credentials_t      @var{res}, const gnutls_datum_t * @var{cert}, const gnutls_datum_t * @var{key}, const char * @var{subkey_id}, gnutls_openpgp_crt_fmt_t @var{format})
