code: func Fprintf(writer io.Writer, reader io.Reader, format string) error {
  
  	return ProcessMessage(reader, func(encodedBytes []byte) error {
  		var decodedObjects []interface{}
  		var row *Row
  		var err error
  		// fmt.Printf("chan input encoded: %s\n", string(encodedBytes))
  		if row, err = DecodeRow(encodedBytes); err != nil {
  			return fmt.Errorf("Failed to decode byte: %v\n", err)
  		}
  
  		decodedObjects = append(decodedObjects, row.K...)
  		decodedObjects = append(decodedObjects, row.V...)
  		fmt.Fprintf(writer, format, decodedObjects...)
  
  		return nil
  	})
  }
docs: // Fprintf reads MessagePack encoded messages from reader,
  // and formats according to a format specifier and writes to writer.