I've decided to compile the Zero Phase Shift.vi filter into a dll. This vi relies on IIR.lsb and IIR.c files.
There is no problems with running the vi itself. However, using a dll that was built from this vi generates a fatal Windows error message
LABVIEW.LIB was not called from a LabVIEW process (for example, if one tries to call the dll from within a VB program)
If I remove the lsb reference from the vi, then calling the dll has no problems. I have tried to reference the IIR.lsb explicitly from the Build Shared Lib wizard, that did not work.
I used LabVIEW 7.1
Andrew