On Fri, 19 Sep 2003 15:49:33 +0200, "Koen" <no@ssppaamm.com> wrote in
comp.lang.c++:
[color=blue]
> Hi!
>
> I have a question about building and then using libraries containing
> C++ code.
>
> Let's say I have some C++ code and a .cpp file with 1 function that
> uses some other C++ code / classes etc... Also, any possible exception
> is handled within the function itself.
>
> In code:
>
> MyModule.h
> ----------
> #ifndef MYMODULE_H
> #define MYMODULE_H
>
> extern int Test(float inParam1,float inParam2,float* outResult);
>
> #endif // #ifndef MYMODULE_H
>
> MyModule.cpp
> ------------
> #include "MyModule.h"
> #include "MyClasses.h" // contains MyClassA and MyClassB
>
> int Test(float inParam1,float inParam2,float* outResult)
> {
> int theResult = 0;
> try
> {
> MyClassA a;
> a.Setup(inParam1);
> MyClassB b;
> b.Setup(inParam2);
> *outResult = a.Process(b);
> }
> catch (...)
> {
> theResult = -1;
> }
> return theResult;
> }
>
> Now, I would like to build a library that is callable from C++ AND
> from C that exposes the functionality of that Test function (I just
> gave an example with 1 single function, but in practice there are
> more).
>
> Currently, when I build the library, it is compiled using the C++
> compiler (of course, since I really use C++ classes and so on), and I
> can use the library from a C++ program (.cpp file with main), as
> should...
>
> But I can't seem to find out how to make that function accessible to a
> C program (.c file with main). I get an error like "unresolved
> external symbol _Test", and I know that it probably has something to
> do with the name mangling in C++ being different from C...
> Considering the fact that the *interface* of the library does not
> contain any C++ specific things, and handles all possible exceptions
> internally, it should be possible to use it in C too, right?
>
> Can someone please explain me how to do that?
> Thanks in advance!
>
> Koen
>
> PS
> If someone wants the test code, I can post/send them on request.
>[/color]
You probably can't use C++ code that does things like throwing and
catching exceptions from inside a C program.
While this is implementation specific, it is often necessary on many
platforms for a program containing mixed C and C++ object modules to
have the start-up and main() in C++. It is quite possible that the C
environment created by the C compiler for a C executable will not have
appropriate support for C++ only features such as exceptions.
--
Jack Klein
Home:
http://JK-Technology.Com
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