Johny,

you must take care of calling convention. I'd suggest to go through the Chapter 18 in Michael Etzel's book on Mixed Language Programming issues (take a look at compiler Attributes like C/STDCALL and ALIAS. Table 18-2, page 486, is very helpful). An (opposite way) example of calling Fortran DLL from C++ you can find here.

Artur

Use dumpbin /exports cppdll.dll to see what the real alias is. See my comments in this thread.

Message Edited by intel.software.network.support on 12-09-2005 09:56 AM

My guess is that since the DLL function is in C++, it has a "mangled" name. We haven't seen the C++ declaration yet.

The routine should start out something like this:

I note that the routine name appears as mixed case in the linker warning, making me wonder if there's a !DEC$ ATTRIBUTES ALIAS there or perhaps /names:asis.

Steve

The directive is being recognized - you can tell because the global name the linker is looking for is in mixed case, due to the ALIAS. If it weren't, it would be looking for _CPPFUNCTION@8.

The problem is in your C++ file, as suggested in my earlier reply. No, the directives don't "unmangle" the name. By default, C++ encodes a routine name and its arguments into a string of gibberish (to us), based on a known algorithm. If you don't know what that gibberish name is, you can't call it from languages other than C++. By adding "C" (in quotes) to the extern declaration, that tells C++ that it's a C routine and to not apply C++ name-mangling.

Steve

You should put extern "C" in both definition and declaration (.h file). I'm not a C++ expert and I'm not exactly sure what disadvantages it can potentially bring;
I think in most "normal" cases you can safely use it.
As you see, you needn't use it necessarily -- personally I think using C++ mangled name is just ugly.