extern int isdn_tty_stat_callback(int, isdn_ctrl *);
extern int isdn_tty_rcv_skb(int, int, int, struct sk_buff *);
extern int isdn_tty_capi_facility(capi_msg *cm);
extern int isdn_tty_stat_callback(int, isdn_ctrl *);
extern int isdn_tty_rcv_skb(int, int, int, struct sk_buff *);
extern int isdn_tty_capi_facility(capi_msg *cm);