thunk_rfb_poll
if (thunk_rfb_poll(&sc->sc_rfb, NULL) == -1)
while (thunk_rfb_poll(&sc->sc_rfb, &event) > 0) {
while (thunk_rfb_poll(&sc->sc_rfb, NULL) > 0)
if (thunk_rfb_poll(&sc->sc_rfb, &event) > 0) {
int thunk_rfb_poll(thunk_rfb_t *, thunk_rfb_event_t *);