LabVIEW

[t_houston]

I've been programming in LV for a couple of decades but have run across an new area I have had zero exposure to.  I am having to fix/support an application written to handle multiple data streams across a network.  It uses VITs.  Can someone point me to a reasonable tutorial/description of VITs and how you set them up, etc?

I am a bit stumped since the code has zero documentation.  There is a queue (been there and done that) but it appears that they are pushing a cluster into it and magically there is another instance of this VIT.  An example or link would do wonders.  I've done a bit of searching but maybe I'm not using the correct magic incantation (key words)

Thanks

[mikeporter · Accepted solution]

In terms of incantations I have found placing the entrails of an unspotted goat on the keyboard at moon-rise to be highly effective...

But seriously though folks... VITs are just VIs with a different file extension. The key difference is that when one is opened (manually or programatically) you get a copy of the routine in memory. Open it 10 times and you get 10 copies of the same code.
Now to your specific problem... Look at the code that is dequeuing the cluster. That is where to start looking for the code calling the VITs.

Mike...

[Akiel]

aah thats were ive been going wrong Ive been waiting for a moonless night....

[t_houston]

Thanks for the info.  The problem is that I/we can't find anywhere that the queue is read and the vi in question is launched.  There must be another vi running that shares the queue but we can't seem to find where or how it is launched.  It has to be there because the vi gets launched.  I love taking over spagetti code with zero comments or documentation.  This is one HUGE convoluted disaster.

Due to not having worked with VITs before, I was wondering if there was some feature I was not aware of that would allow you to automatically fire one off from some type of wierd queue operation. It appears to be quite simple.......if you can find the code. 

[mikeporter]

Well, the queue has to be named so you could try doing a search for the queue name -- or a search on the dequeue function or open VI reference function.

Mike...

PS: Is houston you location or name?

[mikeporter]

Also, if the cluster is a typedef you could look for all the places it occurs.

Mike...

[thouston@iccne…]

I'm a Texas expatriot but that is my name. 

I found the code.  The app was written by a consulting company and apparently they wanted to come back to do upgrades because they tried to make things as difficult to figure out as possible.  They hid the launch VI's behind a white graphic so they did not show up.  They obfuscated everything.as much as possible.  I finally found the code after doing a bunch of find operations.

[mikeporter]

Would it be impolite to ask who the schmucks were that wrote that mess? You might consider it a public service...

Mike...