watch what parameters are pasted to dll

Hello all. I've got a DLL and EXE that was written (in VB I think) a long time ago. I've been asked to find out how the whole thing goes together in hopes of updating it to .NET. I can register the DLL and can get the parameter names and types that it wants but what I'm putting in isn't generating any out put (its a function with a string return). I'm wondering if there is anything out there that would let me see what the original program is sending in to the dll. I've tried to search google but all it gives me is decompiler type stuff that only outputs to assembly which isn't helping. My hacker skills are a bit lacking these days it seems.

Thanks for any input.

Stephen

It's possible you are using it incorrectly. Recheck the parameters it wants and make sure VB is sending the correct type and you are receiving the output in the correct type variable.

I am passing in the right types. Hard to mess up (int,int,long,optional string) as string. I'm just not sure what the original programmer had for those values.

In the database he has id columns that match the variable names for the int,int,long but those values don't seem to return what I expect. That's why I would like to find out what is getting passed in.

It's not like I'm dead in the water and I have a good idea as to what is returned but would like to be sure.

Stephen

I know you think the DLL was written in VB but maybe it was written in C/C++. Integers are different in VB as they are in C/C++. Also, you need to know how the DLL wants it's parameters sent; ByVal or By ByRef. Strings could also be handled differently. Why don't you see for sure if it's a VB or a C/C++ DLL. Without having a copy of it I really can't tell you how to deal with it nor do I know what you can do to find out what it wants.

Thanks for your help. I was looking at the whole program again and it wasn't done in VB. It's in File Maker Pro. What version I don't know. I really shouldn't spend a bunch of time on this as I could rewrite the functions from scratch faster. So unless there is a fairly easy answer to just watching from the OS what parameters are that are passed then its really not worth to much effort.

Thanks again for your help.

Stephen