static void if_set_termios(struct tty_struct *tty, struct termios *old);
static int if_tiocmget(struct tty_struct *tty, struct file *file);
static int if_tiocmset(struct tty_struct *tty, struct file *file,
static void if_set_termios(struct tty_struct *tty, struct termios *old);
static int if_tiocmget(struct tty_struct *tty, struct file *file);
static int if_tiocmset(struct tty_struct *tty, struct file *file,