call by reference using dlls

[Neil.Pate]

Hi there,

I have a question about the behaviour of DLLs when using a call by reference node. If a DLL is loaded in some earlier VI, and a sub-VI of this calls-by-reference another VI which uses the same DLL, will the same instance of the DLL be used, or will LabVIEW load a fresh DLL into memory?

Thanks!

Neil

[BJD1613]

Try this attached example. I am calling the same dll in parallel. What this will do if in highlighted execution is call both but one or the other will have to wait until the first instance of the DLL is finished executing. Once the first instance is done the second instance will execute. So the DLL will not work like a template it will have to call itself again after the first instance unloads itself. Hope this helps.

[Neil.Pate]

Thanks Brandon,

I neglected to mention I am using 7.0, so I can't run the attached VIs, would it be possible for you to save them in 7.0 format?

I have tried something similar before, and the LV IDE loads the DLL once and data can be shared between apps, but when both are compiled this link breaks (like it should I suppose). I am still unsure what happens when a DLL is dynamically loaded loaded using a call-by-reference function.

[BJD1613]

here you go. try this.