cf, err := os.Open(cdf)
		if err != nil {
			return fmt.Errorf("opening counter data file %s: %s", cdf, err)
		}
		defer cf.Close()
		var cdr *decodecounter.CounterDataReader
		cdr, err = decodecounter.NewCounterDataReader(cdf, cf)
		if err != nil {
			return fmt.Errorf("reading counter data file %s: %s", cdf, err)
		}
		var data decodecounter.FuncPayload
		for {
			ok, err := cdr.NextFunc(&data)
			if err != nil {