crossPlatform01.cpp

#ifdef _WIN32
    //Windows
    #include "stdio.h"
    #include <iostream>
    #include "windows.h"
    #include "math.h"
#elif __APPLE__
    #include "TargetConditionals.h"
    #include "stdio.h"
    #include <iostream>
#elif __linux__ //__GNUC__
    // linux
    #include "stdio.h"
    #include <iostream>
#elif __unix__
    // Unix
    #include "stdio.h"
    #include <iostream>
#elif defined(_POSIX_VERSION)
    // POSIX
    #include "stdio.h"
    #include <iostream>
#else
#   error "Unknown compiler"
#endif

using namespace std;

int main(void)
{
    #ifdef _WIN32
    {
        cout<<"Windows world"<<endl;
        system("pause");
    }
    #endif
    #ifdef __APPLE__
    {
        cout<<"Mac world"<<endl;
    }
    #endif
    #ifdef __linux__
    {
        cout<<"Linux world"<<endl;
    }
    #endif
    #ifdef __unix__
    {
        cout<<"Unix world"<<endl;
    }
    #endif
    #ifdef _POSIX_VERSION
    {
        cout<<"Posix world"<<endl;
    }
    #endif
    return 0;
}