ATZ_F_CRITICAL
flags = sc->sc_flags & ~(ATZ_F_CRITICAL | ATZ_F_HOT | ATZ_F_PASSIVE);
flags |= ATZ_F_CRITICAL;
if ((changed & ATZ_F_CRITICAL) != 0) {
sc->sc_flags &= ~(ATZ_F_CRITICAL | ATZ_F_HOT | ATZ_F_PASSIVE);