Call function in c++ dll without header

Question

I would like to call a method from an dll, but i don\'t have the source neither the header file. I tried to use the dumpbin /exports to see the name of the method, but i can

Answer 1

The C++ language does not know anything about dlls.

Is this on Windows? One way would be to:

• open the dll up in depends.exe shipped with (Visual Studio)
• verify the signature of the function you want to call
• use LoadLibrary() to get load this dll (be careful about the path)
• use GetProcAddress() to get a pointer to the function you want to call
• use this pointer-to-function to make a call with valid arguments
• use FreeLibrary() to release the handle

BTW: This method is also commonly referred to as runtime dynamic linking as opposed to compile-time dynamic linking where you compile your sources with the associated lib file.

There exists some similar mechanism for *nixes with dlopen, but my memory starts to fail after that. Something called objdump or nm should get you started with inspecting the function(s).