@deftypefun {int} {gnutls_session_set_id} (gnutls_session_t @var{session}, const gnutls_datum_t * @var{sid}) @var{session}: is a @code{gnutls_session_t} type. @var{sid}: the session identifier This function sets the session ID to be used in a client hello. This is a function intended for exceptional uses. Do not use this function unless you are implementing a custom protocol. To set session resumption parameters use @code{gnutls_session_set_data()} instead. @strong{Returns:} On success, @code{GNUTLS_E_SUCCESS} (0) is returned, otherwise an error code is returned. @strong{Since:} 3.2.1 @end deftypefun