int gnutls_session_get_data2(gnutls_session_t session, gnutls_datum_t * data);
is a gnutls_session_t structure.
gnutls_datum_t * data
is a pointer to a datum that will hold the session.
Returns all session parameters, in order to support resuming. The
client should call this, and keep the returned session, if he wants
to resume that current version later by calling
gnutls_session_set_data(). This function must be called after a
successful handshake. The returned datum must be freed with
Resuming sessions is really useful and speedups connections after
a succesful one.
On success, GNUTLS_E_SUCCESS (0) is returned, otherwise
an error code is returned.