Mixing C and C++

[Kai Henningsen]

SC>What you describe is common in implementations of C++, but does not
SC>usually apply to C.  C++ allows specification of runtime code to
SC>be executed (conceptually) before main(), and (conceptually) after
SC>main() exits.  C provides no such facility to the C programmer, and
SC>it is unusual for a C compiler to require that main() be compiled by
SC>that C compiler (but some have that requirement for other reasons).

Not exactly. ANSI-C specifies that exit() or leaving main() will execute
procedures specified via atexit(), and furthermore specifies that at that
time, stdio-cleanup is performed (files closed, etc.). The latter requirement
exists on every Unix-C. It's the difference between exit() and _exit().

SC>Of the C++ object-code compilers I am familiar with, all provide a
SC>companion C compiler, and none have any requirement on main() that
SC>would prevent mixing C and C++ code.  Some C++ object-code compilers
SC>do not even require main() to be written in C++.

This, of course, is something quite different :-) Whether it gives you a
portable program, however, is something else ...

To overcome the problem, I would suggest to use some my_own_main() in both
languages, and a main() which simply calls that. Then, when porting, you just
modify that trivial main(), which should be simple, provided you have compiler
docs. Use whichever language is more appropriate ...

MfG Kai