Richard Hulme wrote in a message to Kevin Ring:

 RH> I also remember more recently a discussion on Usenet about
 RH> whether or not IBM was going to implement the Win32 API
 RH> directly in this manner or not for future versions of OS/2. 
 RH> Apparently, there is much less of a performance drop when
 RH> "re-routing" the Win32 API - probably due to both using a
 RH> flat memory model (Does the Win32 API use a flat memory
 RH> model?  I don't know *anything* about the Win32 API and very
 RH> little about the Win16 API).

IBM is emulating the Win32 API.  The project is known, appropriately, as
"Dax."

Win32 is not a monolithic API.  Win32 is the NT API, Win32s is the subset
of the NT API which can be provided by extra DLLs on Windows 3.1, and
Win32c is the superset of Win32s (but not a subset of Win32) that is the
Windows 95 API.

And yes, Win32 is a 32-bit flat model.  It looks a lot like OS/2 flat
model, except that you get 4 GB selectors instead of 512 MB selectors.
 
-- Mike


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