int dp_send_error_msg(struct datapath *, const struct sender *,
uint16_t, uint16_t, const void *, size_t);
int dp_update_port_flags(struct datapath *dp, const struct ofp_port_mod *opm);
int dp_send_error_msg(struct datapath *, const struct sender *,
uint16_t, uint16_t, const void *, size_t);
int dp_update_port_flags(struct datapath *dp, const struct ofp_port_mod *opm);