Can a Messenger Channel have multiple readers and writers?

[RTSLVU]

I get that Messenger Channels can have multiple writers but will multiple readers on the same Channel work too? 

Here's a simplified example of what I am asking

I believe the loops should just ignore any messages that they are not programmed to handle. 

Or will there be a race condition where the first loop to dequeue the message gets it but the others don't even see it?

[avogadro5 · Accepted solution]

It seems to work like a queue, so each enqueued element can only be dequeued once.

If you want each reader to get a copy I think you need the Event Messenger channel type and its interesting dataflow requirements.

[RTSLVU]

Damn you are right, I just ran a quick test and the Messenger Channels act like a Queue with multiple readers there's a race condition dequeuing the channel and only the first "reader" to dequeue the message gets it. 

Oh well I just wanted to save some wires on my block diagram.  

[Quiztus2]

Event MessengerM Channel Wire Toolkit for LabVIEW - Download - VIPM by JKI

you can specify the receiver by an integer or string using that toolkit.

[RTSLVU]

I will give that a look for my next project. At first glance though I'm not sure if it will work for this project without a lot of rewriting code. My architecture is basically a QMH but with Messenger channel wires. My message contains a text "command" for the state machine in the receiving loop and an optional variant payload.   

[Quiztus2]

Your usecase is exactly what this was created for.

[crossrulz]

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@RTSLVU wrote:

Damn you are right, I just ran a quick test and the Messenger Channels act like a Queue with multiple readers there's a race condition dequeuing the channel and only the first "reader" to dequeue the message gets it.

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If you dig into the generated Channel VIs, you will find that it is mostly just a wrapped up queue. So this behavior makes complete sense.