rfs4_client_setcb
rfs4_client_setcb(cp, &args->callback, args->callback_ident);
rfs4_client_setcb(cp_confirmed, &args->callback,
rfs4_client_setcb(newcp, &args->callback, args->callback_ident);
extern void rfs4_client_setcb(rfs4_client_t *, cb_client4 *,