#include unsigned int new_style_hook(const struct nf_hook_ops *ops, /* not: unsigned int hook; */ struct sk_buff *skb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { (void) ops; (void) skb; (void) in; (void) out; (void) okfn; return 0; } struct nf_hook_ops netfilter_ops = { .hook = new_style_hook };