Writing a library for linux and windows?

[KarlisRepsons]

Hi,
perhaps someone can give some links or other info about how should a C++ library be written, so it can be compiled for both Linux and Windows applications?

[helios]

Generally speaking, any program that uses nothing but what the language provides and doesn't rely on undefined behavior is completely portable.
For example,

extern "C" const char *f(){
    return "Hello, World!\n";
}

It's using system calls, such as CreateFile() or fork(), and assuming different things about the system, such as a given endianness or type size, that introduce portability problems.

If you can give more details, we may be able to provide better defined advice.

[KarlisRepsons]

Well, thanks... Too general question, sorry. Maybe later I come back here...