Question

Possible Duplicate:
How to check (via the preprocessor) if a C source file is being compiled as C++ code

I’m trying to find a standard macro which will test whether a header file is being compiled as C or as C++. The purpose of this is that the header may be included by either C or C++ code, and must behave slightly differently depending on which. Specifically:

In C, I need this to be the code:

extern size_t insert (const char*);

In C++, I need this to be the code:

extern "C" size_t insert (const char*);

Additionally, is there a way to avoid putting #ifdef’s around every declaration in the header?

Answer 1

It is normal to bracket C header files as follows so they can be used in C++ programs. Check your system header files such as stdio.h and you will probably see this:

#ifdef __cplusplus
extern "C" {
#endif

...

#ifdef __cplusplus
}
#endif