// Process the measuring points.
func MeasuringPointsDo(f func(*MeasuringPoint)) {
    // Get a channel with the measuring points.

    outChan := make(chan *MeasuringPoint)

    measuringPointOutChanChan <- outChan

    // Process the points.

    for mp := range outChan {
        f(mp)
    }
}



// The measuring backend goroutine.
func etmBackend() {
    measurings := make(map[string]*MeasuringPoint)

    for {
        select {
        case measuring := <-measuringInChan:
            // Received a new measuring.
            if mp, ok := measurings[measuring.id]; ok {
                // Measuring point found.
                mp.update(measuring)

                measurings[measuring.id] = mp
            } else {
                // New measuring point.
                measurings[measuring.id] = newMeasuringPoint(measuring)
            }
        case outChan := <-measuringPointOutChanChan:
            // Retrieve the measuring points.
            go func() {
                for _, mp := range measurings {
                    outChan <- mp
                }
            }()
        }
    }
}