LV2010 Network Streams Bug

[viScience]

It appears that you cannot create a Network Stream datatype of a cluster that contains a variant.

For example a datatype of a cluster containing a string, a variant and a boolean does not work correctly.

I am not sure if this is a bug or a restriction in the range of valid datatypes for this API.

[jareds]

Hi sachsm,

Maybe you should post your code, because I'm able to pass data that has a cluster containing a string, a variant, and a boolean.  Also, what's your system configuration?  OS?  32-bit or 64-bit LabVIEW?  What are you streaming data between?

[viScience]

Actually the problem is in how the Read (or Write) Network Stream vi's propogate the data type.  Take a look at the attached image that depicts what I am talking about.  Start with a simple cluster type that just has a single string in it.  Check the cluster output from the read vi and see that it did not update with the correct type.  Then add a boolean and observe that it then decided to propogate the string, continue in this manner with say a variant and see the trend continue.  As you observed in your testing, this does not mean that the Network Stream does not work once you get it going but it seems there might be a bug in 'design' phase.

[jareds]

I hadn't noticed that.  It definitely looks like that shouldn't be happening.  I'll look into this a little further and see if there's anything that we can do or are doing wrong.

[reddog]

This appears to be an editor bug with LV 2010 in regards to how the data type of the terminal gets updated.  While I can't reproduce the issue you've described exactly, there's definitely issues with getting the cluster to update when changing the names of the cluster elements after wiring the cluster to the data type terminal of the Create VI.  I'm generally able to get the cluster to update when adding elements to the cluster, but it's certainly possible I'm missing something from how you're interacting with the diagram.  We hope to fix this issue for the LV 2011 release.  In the meantime, you should be able to use the unbundle instead of unbundle by name to work around the problem.  Also, I believe another work around would be to delete the wire from the data type terminal of the Create VI, save the VI, close LV, and restart LV.  After restarting LV, the unbundle by name should update appropriately once you wire the data type of the Create VI again (at least it did in the few tests I conducted).