CARP_NL_STATE
snl_add_msg_attr_u32(&nw, CARP_NL_STATE, carpr->carpr_state);
{ .type = CARP_NL_STATE, .off = _OUT(carpr_state), .cb = snl_attr_get_uint32 },
{ .type = CARP_NL_STATE, .off = _OUT(state), .cb = nlattr_get_uint32 },
nlattr_add_u32(nw, CARP_NL_STATE, sc->sc_state);