How to call Fortran .dll file that using other library files?

Question

Hi,
I am trying to do some arkward tasks using LabView, and I am desperately need help....
 A little bit background:
1. My co-worker has some code written in Fortran, where he called other libraries (many from CERNLAB or PAW). Those stuffs are pretty powerful in mathmatical calculation and simulations.
2. In some of my LabView code, I need to call his Fortran source code in order to do some complicated calculations. I have no capablility to translate his Fortran code to Labview (or is it even possible??), so we end up with trying to use "Call library function node" where I just provide input/outputs to communicate with his code. The idea sounds simple enough?
3. We complie the Fortran code into .dll, and then specifiy the dll in "Call library function node". The first try with a very simple Fortran code, something like c = a+b*a, was sucessful. The dll file and Call lib function worked good. It's sort of proved the concept.
4. Now I am trying more complicated Fortran code (say Test.dll), which calling other library (.lib files) that using typical "call xxx(a,b,c)" line, and my nightmare started....  It seems nothing was excuted when I call Test.dll in LabView.
Questions:
1. How do LabView know if the Test.dll code needs functions from other .lib files? Do I need to copy all the .lib files to a specific folder?
2. When I create .dll file, for LabView to be able to use it, are there any special requirement on the way the .dll is compiled?
3. Seems there is mismatch btw the data type in Fortran and LabView. For example, LabView's  Signed 8-bit Integer seems different with a integer in Fortran. How can i know the correlation btw data type in different langurage, i.e. LabView vs Fortran?
4. Are there any good examples that I can take a look?
I would highly appreicate any suggestions/helps!
Rgds,
Harry

Answer 1

You are aware that Intel Visual Fortran is the successor to Compaq Visual Fortran (I think you made a mistype with the Virtual)? So an upgrade might be at its place.
Anyhow I'm really not familiar with Fortran at all, but lib files are usually compiled into an EXE or DLL and not loaded dynamically. 1) 
So there should be no problem with locating those libs. What most likely is a problem are other DLL dependencies such as any Fortran Runtime library or possibly other third party DLLs the more advanced code in your DLL might be using.
Typically most compilers can be configured to link the runtime library code statically into the DLL, as altenbach reports for the Intel compiler, otherwise you must make sure to install the  redistributable Fortran Runtime Library for your compiler. Besides that you must make sure to find out what other runtime dependencies your code might have and install them.
1) One exception I know of is LabWindows CVI which allows to also load lib files dynamically. This is supposedly a legacy feature from LabWindows for DOS, which allowed that feature to simulate dynamic module loading in order to swap modules at runtime to work around the 640k memory limitation of DOS.
Rolf Kalbermatter
CIT Engineering Netherlands
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