int compat_mc_setsockopt(struct sock *, int, int, char __user *, unsigned int,
int (*)(struct sock *, int, int, char __user *,
unsigned int));
-int compat_mc_getsockopt(struct sock *, int, int, char __user *, int __user *,
- int (*)(struct sock *, int, int, char __user *,
- int __user *));
struct compat_group_req {
__u32 gr_interface;