int seat_set_active(Seat *s, Session *session);
int seat_active_vt_changed(Seat *s, int vtnr);
int seat_read_active_vt(Seat *s);
int seat_set_active(Seat *s, Session *session);
int seat_active_vt_changed(Seat *s, int vtnr);
int seat_read_active_vt(Seat *s);