int status = tty_register_ldisc(N_HDLC, NULL); 
int status = tty_unregister_ldisc(N_HDLC); 
static void __exit n_hdlc_exit(void){	/* Release tty registration of line discipline */	int status = tty_register_ldisc(N_HDLC, NULL);	if (status)		printk(hdlc_unregister_fail, status);	else		printk(hdlc_unregister_ok);}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/64ccd715d3cf498318b14b646ce5f97e7ab15bb5/n_hdlc.c/clean/drivers/char/n_hdlc.c