[RESOLVED] Is Binary Compatibility the Answer?

[NWilliams]

Greetings all,

I have done quite a bit of searching on this forum as well as Google to try to find a direct answer to the question I'm about to ask. There have been several similar questions and all advice points to 'use binary compatibility'.

I have authored an Active-X DLL that contains some fairly sensitve code that I will be licensing to several vendors. I do this because selling source code isn't an option since none of these vendors' software is written in VB6. The DLL performs a function of which there will only be one parameter passed, and a string returned - this will simply never change (export structure, that is). The inner workings of said function will, however. In fact it will change often.

The vendors are working with languages such as cpp and vb.net. I have created this DLL and it works fine with my own projects (both client app and DLL in VB6) - until I recompile the DLL after an update and attempt to simply replace the DLL in the system directory (the DLL is registered upon installation).

My question is this: When using binary compatibility, will this have any affect on the update-ability of the vendor's software? Would the VB Active-X DLL easily interop with say.. C++ like one would imagine? (yes, I know the entire point of Active-X is interoperability) The goal is that these softwares will be written, and the only thing that will need to be updated in their application is the function that my DLL performs - so the only thing needing to be updated is the physical DLL without them having to recompile their software at all.

The binary compatibility option in the project's properties is confusing in that I must select a file. I assume this file being selected would be the binary file that it is compatible with? This is ambiguous in that I want to use the same DLL with all vendors' software - which won't even exist at the time of first compile so I have no idea of their binary. Is this possible? It is acceptable if I must create a version for each, however I would like to avoid that.

Thanks in advance for any advice or resources you guys/girls could point me toward, or answers you can provide.

[techgnome]

Look in my sig... there's a link to a tutorial about binary compatibility.... it should answer all your questions.
But in short, yes, binary compatibility is what you need.

-tg

[NWilliams]

Thank you very much, this looks to be exactly what I was hoping to find. Looks like if I would have searched more thoroughly I would have found the post you link to. My appologies for taking up space. Mod can lock the thread if they like.

In the event anyone reaches this thread searching for the same answer, and his signature has changed, he was referring to this thread.