tag	line	file	source code
hangup	1733	drivers/char/serial.c	tty->hangup = rs_hangup;
hangup	270	drivers/char/tty_io.c	if (tty->hangup)
hangup	271	drivers/char/tty_io.c	(tty->hangup)(tty);
hangup	265	include/linux/tty.h	void (*hangup)(struct tty_struct *tty);