DLL created by labview get stuck

[tomer-p]

I tried to run test created with lab view with external tool.

This tool load dll and call execution function.

I created a dll from the Labview test (I used simple function for test that only extract numbers) and I used __stdcall

when I use this dll from an executable It works fine. (My application call a dll, and the dll call to the dll created from labview)

however when I use it from my dll it get stuck

I tried to load the dll dynamically with loadLibrary() and It works fine only for the first time (It gets stuck when I called it again)

I found that if I call it from the same thread it works fine, but if I call it from two different threads (the second call is long after the first call has finished, so there is no race condition) It gets stuck from the second thread.

I used visual studio to see where the call get stuck, and it is in lvrt.dll 

Does anyone know what can I do to solve this problem.

[Lycangeek]

Although the writeup is about .NET, the issue is the same, so check out http://detritus.blogs.com/lycangeek/2005/05/labview_and_asp.html

The problem might be that the first thread is not pumping messages and so the LabVIEW gets hung up waiting for events. This problem has been fixed in LV 8 so I'm assuming you're using an earlier version. If so, you can follow the steps outlined in the link above (creating a message pumping thread and calling your DLL with that first).