PF_APPLETALK
sk = sk_alloc(net, PF_APPLETALK, GFP_KERNEL, &ddp_proto, kern);
.family = PF_APPLETALK,
.family = PF_APPLETALK,
sock_unregister(PF_APPLETALK);
sock_unregister(PF_APPLETALK);
MODULE_ALIAS_NETPROTO(PF_APPLETALK);
[PF_APPLETALK] = "PF_APPLETALK",
case PF_APPLETALK: