ttyclose(tp);
sabttyclose(dev, flags, mode, p)	dev_t dev;	int flags, mode;	struct proc *p;{	struct sab_softc *bc = sab_cd.cd_devs[SAB_CARD(dev)];	struct sabtty_softc *sc = bc->sc_child[SAB_PORT(dev)];	struct tty *tp = sc->sc_tty;	int s;	(*linesw[tp->t_line].l_close)(tp, flags);	s = spltty();	if ((tp->t_cflag & HUPCL) || ((tp->t_state & TS_ISOPEN) == 0)) {		sabtty_mdmctrl(sc, 0, DMSET);		sabtty_flush(sc);		sabtty_reset(sc);	}	splx(s);	ttyclose(tp);	return (0);}