TTY_HUPPED
clear_bit(TTY_HUPPED, &tty->flags);
clear_bit(TTY_HUPPED, &tty->flags);
if (test_bit(TTY_HUPPED, &tty->flags)) {
set_bit(TTY_HUPPED, &tty->flags);
if (test_bit(TTY_HUPPED, &tty->flags)) {