What does the framework executable do?

I'm porting a Windows run-time SDK (headers and DLLs) to the Mac. Since it was my first such experience, I mimicked what I had done when I did this for Linux; I put the dylibs in /usr/local/lib and the headers in /usr/local/include and all was well until I started thinking about distribution and installation, at which point I learned about frameworks. Now I have a framework, which I'll call Foo, and it is at /Library/Frameworks/Foo.framework. My "demo" program, which is built with GCC/Make, and has a "-framework Foo" in the compile command, compiles okay, but the linker cannot find the framework. I then discovered that there must be a "Unix executable" named Foo, but I can find no documentation that tells me what that consists of. All the Apple document says, in effect, "delegate all that to XCode"; but I've invested a lot of time in using gcc/make to do all this, and starting over with XCode would be a big detour for me. So is there documentation that tells me explicity what goes into that executable?

What does the framework executable do?
 
 
Q