C->Cdll->C#dll under VS2008

Hello experts !
I try to implement the following calling chain (for history reasons, thus is a given):
C (.c file, main) -> calling C(.c file dll) -> calling C#(cs. file dll). All that’s under VS2008. Of course, between the C dll and the C# dll I have implemented a COM model, works fine; between the C main and the C dll is basic (I use a .def file for the C dll). The compiler is C++ for the C projects.
Now, with the C-C dll working ok, I try to insert #import <the C# tlb library> into the C dll to start building the COM to the C#. The build of the C dll says error 2773, i.e. I need to use the C++ compiler (which is the case, and referenced into the project’s properties). As soon as I change the C dll source file type to .cpp the build goes through, but not anymore the one of the C main (error LNK 2019, doesn’t find the C dll function). All starts from the 2773 error which is not in accordance with the project’s settings. Any hints?
Thanks!

To call from C functions compiled with C++ you need in the function prototypes add
extern "C"

you could wrap the contents of the h file that contains the dll-interface used by the main
inside the following code

Code:

---

#ifdef __cplusplus
extern "C" {
#endif

/* here go all the function prototypes that should be called from the pure C */


#ifdef __cplusplus
}
#endif

---

Thanks Vart! I put it into the .h file.