"undefined symbol" error while using a custom instrument driver

Question

Hello all, I'm facing a problem related to instrument driver creation.
I want to pack a part of my code to a .FP to be able to reuse it in other applications of mine. This part of code includes calls to Windows API and a third party dll. I have included both windows.h and the include for the dll in the header file for the instrument. I developed the source code and next a little application that simply calls one function to test the result of my work, but I get some 'undefined symbol' errores while linking the test application with the instrument. The instrument header file is included in program source file.
Situation is as follows:
I can run the test application if I include the source file for the instrument directly in the project (without loading the instrument)
I created a static library and can have the test program up and running if directly including the library in the project (again without the .fp file)
I get linker errors when trying to use the instrument I created based on the same code, both when including the instrument at source code level and when including at library level. Adding the .fp to the project makes no difference
Linker errors are all related to WinSDK and third-party dll functions.
Question is: where and how I have to declare the symbols apart including the appropriate .h files in the instrument header file?
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Answer 1

Being waited on to log on... how flattering
I wish I had a simple and obvious solution, but I don't.
The problem in this case is that, whereas DLLs (via their import libraries) carry no additional build-time dependencies to their clients, that is not the case with object files and static libraries: any project that uses those .obj and .lib files must satisfy all of their dependencies when that project builds.
There is a mechanism, with .fp files, to advertise such dependencies to the clients of the .fp, and that is the auto-load list (Edit>>FP Auto-Load List, in the function tree editor). The caveat, however, is that these indirect dependencies must have a companion .fp that you can add to this list. And in your case, you don't have one. So the only solution I can think of is for you to create a very thin wrapper module where you would wrap all of the SDK functions that you need, then create a basic .fp for this wrapper -- you can do this semi-automatically, from the header file (Options>>Generate Function Tree) -- and then add this .fp to the auto-load list of your primary .fp. And then you'll probably have to create a second .fp wrapper for your other dependency (a non-SDK third-party DLL?).
Once you have declared the dependency chain for this .fp, you should then be able to use it on any test application and CVI should know to link in these additional static libraries whenever it builds the test application.
If you choose to go this route, you'll probably have to deal with a bunch of non-standard data types in the parameters of the SDK functions. I don't remember if these are automatically added to the .fp when you create it from the header file. If not, all you need to do is add them to the .fp  later (Options>>Data Types, from the function panel editor). Don't worry about providing the definitions for these data types. They're not necessary. You just need to make sure that their names are in the list.
Luis
Message Edited by LuisG on 05-19-2010 10:43 AM