int gnutls_certificate_type_set_priority(gnutls_session_t session, const int * list);
is a gnutls_session_t structure.
const int * list
is a 0 terminated list of gnutls_certificate_type_t elements.
Sets the priority on the certificate types supported by gnutls.
Priority is higher for elements specified before others.
After specifying the types you want, you must append a 0.
Note that the certificate type priority is set on the client.
The server does not use the cert type priority except for disabling
types that were not specified.