@deftypefun {int} {gnutls_x509_tlsfeatures_init} (gnutls_x509_tlsfeatures_t * @var{f}) @var{f}: The TLS features This function will initialize a X.509 TLS features extension structure @strong{Returns:} On success, @code{GNUTLS_E_SUCCESS} (0) is returned, otherwise a negative error value. @strong{Since:} 3.5.1 @end deftypefun