port_update_poll_desc
if (!port_update_poll_desc(port, port->net_rbio, /*for_write=*/0))
if (!port_update_poll_desc(port, port->net_wbio, /*for_write=*/1))
if (!port_update_poll_desc(port, net_rbio, /*for_write=*/0))
if (!port_update_poll_desc(port, net_wbio, /*for_write=*/1))