Function ttydev_close

freebsd/kern/tty.c:373–412

}

static int
ttydev_close(struct cdev *dev, int fflag, int devtype __unused,
    struct thread *td __unused)
{
	struct tty *tp = dev->si_drv1;

	tty_lock(tp);

	/*
	 * Don't actually close the device if it is being used as the
	 * console.
	 */
	MPASS((tp->t_flags & (TF_OPENED_CONS | TF_OPENED_IN)) == 0 ||
	    (tp->t_flags & TF_OPENED_OUT) == 0);
	if (dev == dev_console)
		tp->t_flags &= ~TF_OPENED_CONS;
	else
		tp->t_flags &= ~(TF_OPENED_IN|TF_OPENED_OUT);

	if (tp->t_flags & TF_OPENED) {
		tty_unlock(tp);
		return (0);
	}

	/* If revoking, flush output now to avoid draining it later. */
	if (fflag & FREVOKE)
		tty_flush(tp, FWRITE);

	tp->t_flags &= ~TF_EXCLUDE;

	/* Properly wake up threads that are stuck - revoke(). */
	tp->t_revokecnt++;
	tty_wakeup(tp, FREAD|FWRITE);
	cv_broadcast(&tp->t_bgwait);
	cv_broadcast(&tp->t_dcdwait);

	ttydev_leave(tp);

	return (0);
}

static __inline int
tty_is_ctty(struct tty *tp, struct proc *p)