GUS_DMAIN_ACTIVE
sc->sc_flags |= GUS_DMAIN_ACTIVE;
sc->sc_flags &= ~GUS_DMAIN_ACTIVE;
sc->sc_flags &= ~GUS_DMAIN_ACTIVE;
sc->sc_flags &= ~(GUS_OPEN|GUS_LOCKED|GUS_DMAOUT_ACTIVE|GUS_DMAIN_ACTIVE);
if (sc->sc_flags & GUS_DMAIN_ACTIVE) {