CONS_POLL
if ((sc->sc_flags & CONS_POLL) == 0) {
sc->sc_flags |= CONS_POLL;
sc->sc_flags &= ~CONS_POLL;
if (sc->sc_flags & CONS_POLL)
sc->sc_flags &= ~CONS_POLL;
if ((sc->sc_flags & CONS_POLL) == 0) {
sc->sc_flags |= CONS_POLL;