BWI_F_STOP
sc->sc_flags &= ~BWI_F_STOP;
sc->sc_flags |= BWI_F_STOP;
(sc->sc_flags & BWI_F_STOP)) {
if (sc->sc_flags & BWI_F_STOP) {
!(sc->sc_flags & BWI_F_STOP))
if (sc->sc_flags & BWI_F_STOP) {
|| (sc->sc_flags & BWI_F_STOP))