Int 2F Fn 1688  U - Ms Windows 3.0, 386max V6.01 - Get Alias Selector To   [W]

   AX = 1688h
   BX = 0BADh

Return: AX = 0000h if supported
       BX = alias selector for LDT

Note:  use the LSL instruction or GetSelectorLimit() to find LDT size
   this call should be considered obsolete for Windows 3.1+, as the
     alias selector can be retrieved via the API entry point for
     "MS-DOS" retrieved from INT 2F/AX=168Ah (see #2407)

See Also: AX=1687h,#2407