DLL build by Labview App Builder doesn't work if Built-IN functions used!?

Question

Hi All,
I hope somebody shed some light on this;
(All VIs are in the attached case1-2.zip)
Case 1:
A VI reads a 1D array data and Uses RMS.vi to calc the rms of the data and returns the rms value and the error value. (make1_dll.vi).
This VI is used to build a DLL. (test1.dll using the test1.bld)
Call this DLL in a new VI (just to test that the DLL works) (test1.vi)
RUN the new VI >>> Result Nothing happens No Error or Crash and No result!!!
Case2 :
Build the above without using the “RMS.vi” and works OK. (see case2 VIs)
Any idea why the build-in function doesn’t work?
Best regards
Attachments:
case1-2.zip ‏44 KB

Answer 1

Joel A wrote:
You might want to look at the path building you are doing to find the RMS VI. If you are using relative paths, then LabVIEW calls like "VI Path" will have an extra path if the VI is an exe or inside an LLB.
Drop some probes (indicators, outputs, etc.), rebuild and double check the paths. I've been burned by this before...
If this is the case, you can use the VI properties, or path parsing to solve it.
joel
I don't think that is the problem. The RMS.vi is referenced as statically linked VI in the make1_dll.vi.
As such it should be linked into the LabVIEW DLL as well. What I suspect is the problem is the fact that
the RMS.vi uses the lvanlys.dll and that for some reason there is something going wrong with the LabVIEW
test1.dll, which runs in the LabVIEW runtime context, calling lvanlys.dll while executed in the context
of LabVIEW itself. Probably something to do with the changes to how lvanlys.dll is treated between LV 7.0
and 7.1.
I see this same behaviour on my system too, so an installation problem is quite unlikely. Other than that calling a LabVIEW dll from within LabVIEW makes not that much sense (but did work fine in the past save from some hassles in 6.0 and 6.0.1), I have no explanation why this doesn't work.
Rolf Kalbermatter
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions