c++ #ifdef Mac OS X question

According to this answer:

#ifdef __APPLE__
    #include "TargetConditionals.h"
    #ifdef TARGET_OS_IPHONE
         // iOS
    #elif TARGET_IPHONE_SIMULATOR
        // iOS Simulator
    #elif TARGET_OS_MAC
        // Other kinds of Mac OS
    #else
        // Unsupported platform
    #endif
#endif

So in short:

#ifdef __APPLE__
    #include "TargetConditionals.h"
    #ifdef TARGET_OS_MAC
        #include <GLUT/glut.h>
        #include <OpenGL/OpenGL.h>
    #endif
#elif defined _WIN32 || defined _WIN64
    #include <GL\glut.h>
#endif