code: func (s *TxSubmitter) SubmitTransactionWithChan(txEnvelope *common.Envelope, eventCh chan TxEvent) (committed bool, txId string, err error) {
  	committed, txId, err = s.sendTransactionInternal(txEnvelope, context.Background(), eventCh, false)
  	return
  }
docs: // SubmitTransactionWithChan submits a token transaction to fabric with an event channel.
  // This function does not wait for transaction commit and returns as soon as the orderer client receives the response.
  // The application will be notified on transaction completion by reading events from the eventCh.
  // When the transaction is committed or failed, an event will be added to eventCh so that the application will be notified.
  // If eventCh has buffer size 0 or its buffer is full, an error will be returned.