pfil_head_get
pfh = pfil_head_get(PFIL_TYPE_AF, AF_INET);
pfh = pfil_head_get(PFIL_TYPE_AF, AF_INET);
pfh = pfil_head_get(PFIL_TYPE_AF, AF_INET);
pfh = pfil_head_get(PFIL_TYPE_AF, AF_INET);
pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
struct pfil_head *pfil_head_get(int, u_long);