code: func handleGetNetTotals(s *rpcServer, cmd interface{}, closeChan <-chan struct{}) (interface{}, error) {
  	totalBytesRecv, totalBytesSent := s.cfg.ConnMgr.NetTotals()
  	reply := &btcjson.GetNetTotalsResult{
  		TotalBytesRecv: totalBytesRecv,
  		TotalBytesSent: totalBytesSent,
  		TimeMillis:     time.Now().UTC().UnixNano() / int64(time.Millisecond),
  	}
  	return reply, nil
  }
docs: // handleGetNetTotals implements the getnettotals command.