PF_RT_DNPIPE
snl_add_msg_attr_u16(nw, PF_RT_DNPIPE, r->dnpipe);
{ .type = PF_RT_DNPIPE, .off = _OUT(r.dnpipe), .cb = snl_attr_get_uint16 },
{ .type = PF_RT_DNPIPE, .off = _OUT(dnpipe), .cb = nlattr_get_uint16 },
nlattr_add_u16(nw, PF_RT_DNPIPE, rule->dnpipe);