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REx - Remote Export Framework and Remote Events

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lEver wanted to communicate with VI which are across context boundaries?

Those typical boundaries, are

  • different LabVIEW project

  • LabVIEW into LabVIEW EXE,

  • EXE to EXE

  • PC to PC across a network or even the internet


Usually to get around these boundaries, we have to flatten to some easier transport mechanism like a string and then unflatten on the other end.


There are a whole other host of situations and and reasons why cross context boundary communication is useful and not just a simple slam dunk using existing primitives in LabVIEW


REx (Remote Export Framework) is a useful framework that you can take advantage of to eliminate the typical boundaries

Instead of spend 45 minutes trying to describe it, see the linked videos below, (also in the PPT) until more written content gets made.


Basic Demo - Current App http://screencast.com/t/JbW2mM3jx


Creating & Using a New Command http://screencast.com/t/GhkE2CEx4Ip

Send into EXE http://screencast.com/t/bxbI0B4l8Xs

EXE to EXE http://screencast.com/t/xCJw2B39mFQr

Debugging Ports / Services http://screencast.com/t/E0RXrgM3Yex
Rebuild of EXE (addendum) http://screencast.com/t/36oWmrybjRMj
1/12/15 Update: attached new VIPC which upgrades REx to to address the issues w/ things not moving into the tools menu properly

Remote Export – REx Framework.pptx

REx Installation Full.vipc

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Please check out the attached files that I did a save for previous on.

I don't have 2011 on my pc (or the time to check the install at the moment) so if you could see if it's operational for you that'll help me out (along w/ anyone else that wants to use the 2011 version)




Thanks for the port!

I've just tested on my machine with LV2011 and it works just fine. I was able to run the DEMO Command Sender.vi & DEMO Command Listener.vi in the development environment, as well as the sender in the IDE and the listener as separate executable. No relinking issues or any kind of problem with file versions this far.


EDIT: Well ok, the Rex_Sprinboard library seems to miss some files for generating user icons and such. I guess that's just not available in LV2011. It's missing files from ..vi.libLabVIEW Icon API*

Does my installation miss something?

Edited by LogMAN
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Thanks Norm

I can open Rex.LVLib without problem in LV2011.

Your Zip contain Session-Root.Lvclass too. is it normal?

Please, is it possible to have your exempl in LV2011 ? Oups i see them in other folder

Best regards

Eric Bobillier

Edited by Bobillier
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EDIT: Well ok, the Rex_Sprinboard library seems to miss some files for generating user icons and such. I guess that's just not available in LV2011. It's missing files from ..vi.libLabVIEW Icon API*

Does my installation miss something?

All, I can't do much about the Icon stuff for the 2011 port as a lot changed around those versions.

Your best bet is simply to edit the Command Creator Springboard and comment out the icon modification part of the code.

It should be easy to find but if you run into trouble let me know and I'll direct you along.


Hi Norm After few controls , it appears that one def-type ( KeyedArray.ctl)is missing in your dependency for the Rex_Sprinboard,and all about ICON API are missing too. Eric

KeyedArray.ctl should make it's way onto your PC if you install AMC from the tools network.

I'm sorry about the dependency, but because I'm not going to spend too much time on the 2011port, hopefully this will work

Please let me know if that doesn't


Happy wireworking


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  • 2 months later...

Hello Norm,


Thanks for your work!

I installed the REx using "REx Installation Full.vipc" in LabVIEW 2012 SP1.

Everything is working perfect (the same as described in videos), but I can't create a new command with the "MAIN - Create New REx_CMD.vi".

I have the attached error message displayed when press "Build".


Can you help me to resolve this issue?








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  • 2 weeks later...

Is it possible that the REx to send/receive data between two EXE on the same local host, but build from different projects?




This allows you to talk between ANY LabVIEW instance irrespective of the boundary.

Good luck!

The only thing to be very intentional in setting up, is making sure that you have the right 'Service Name' configured for the listener and pointing to that specific one on the remote connection


Good luck

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Very, very cool, Norm. :)


Let's say I wanted to remotely monitor a test system. Would it be breaking to have the remote system broadcast its disposition to the entire network every 30 seconds or so, ignoring errors in the case that no listeners are running? What are the limits of data types that can be passed? What would be the ideal way to show the entire front panel of the remote system? Duplicate the front panel on a listener, bundle the data on the sender, then unbundle on the listener?


Edit: I'm imagining more than just the remote panel capabilities built into LabVIEW.


Edit 2: So I upgraded from (installed when I installed TLB`, I think) to the version attached here (, and now the REx»New Command button is gone from my tools menu, and the examples folder went from having the source files shown in your video, to only having the Listener exe and ini in it. It's like it uninstalled what I had and didn't replace it. I did uninstall the whole package and reinstall it, and restart LabVIEW, but no joy.


Edit 3: Ok, I found the demos, at least. Looks like everything is in user.lib now. Were the tools menu options supposed to go away?


Ryan R.

Edited by RnDMonkey
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Well, after a full system restart, the menu options are back, and creating a new command worked! Amazing what restarting a Winblows machine can do!


Ryan R.


I'm sorry for all the troubles.

It's true that I haven't done as much testing of the install w/ the recent builds.

I'll double check and re-post the updates that you found. Thank you!


Also, since you've now got command creation going, are you able to get it to talk across the boundaries you need?



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How secure are the messages communicating this way via tcp/ip and the vi server (correct me if this is not the case)?

Is it open to simple sniffing/wireshark/viserver listen to all?

I know this is not a specific issue for REx, I just thought that you might have a solution maybe by communication between processes in memory for local machines or hashing/encrypting the messages.

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