What's with “#ifdef _MAC” in Windows header files?

Question

I was browsing through Windows\'s Platform SDK header files (what a life, right?), and I noticed many places contained references to the preprocessor symbol _MAC. F

Answer 1

As you can see in Windows.h header file, macro _MAC is defined as follows:

#if defined(_68K_) || defined(_MPPC_)
#define _MAC
#endif
#endif

So, yes, it is defined only for old macOS environment (before it started to use intel processors)