ATMIOC_SPECIAL
#define ATM_NEWBACKENDIF _IOW('a',ATMIOC_SPECIAL+3,atm_backend_t)
#define ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL+4,struct atm_iobuf)
#define ATM_DROPPARTY _IOW('a', ATMIOC_SPECIAL+5,int)
#define ATM_SETSC _IOW('a',ATMIOC_SPECIAL+1,int)
#define ATM_SETBACKEND _IOW('a',ATMIOC_SPECIAL+2,atm_backend_t)
#define ATMSIGD_CTRL _IO('a',ATMIOC_SPECIAL)
#define COMPAT_ATM_ADDPARTY _IOW('a', ATMIOC_SPECIAL + 4, struct compat_atm_iobuf)