Function cngrab

freebsd/kern/kern_cons.c:372–383

    "Console device control");

void
cngrab()
{
	struct cn_device *cnd;
	struct consdev *cn;

	STAILQ_FOREACH(cnd, &cn_devlist, cnd_next) {
		cn = cnd->cnd_cn;
		if (!kdb_active || !(cn->cn_flags & CN_FLAG_NODEBUG))
			cn->cn_ops->cn_grab(cn);
	}
}

void
cnungrab()