socket_ioctl
extern int socket_ioctl(struct sonode *, int, intptr_t, int, struct cred *,
return (socket_ioctl(so, cmd, arg, mode, cr, rvalp));
error = socket_ioctl(so, FIOASYNC, (intptr_t)&async, FKIOCTL,
rval = socket_ioctl(so, cmd, arg,