Int 21 Fn 4412  O - Dr Dos 5.0-6.0 - Determine Dos Type                    [O]

   AX = 4412h
   CF set

Return: CF set if not DR DOS
       AX = error code (see #1366 at AH=59h/BX=0000h)
   CF clear if DR DOS
       DX = AX = version code (see #1267)

Note:  this obsolete call, which is no longer supported in Novell DOS 7, is
     identical to AX=4452h

See Also: AX=4452h