Int 2F Fn 5601  - Interlnk - Check If Redirected Drive                     [R]

   AX = 5601h
   DX = magic value FFFFh
   BH = drive number (0=A:)
   BL = instance number (00h=any, 01h=first loaded, etc.)

Return: (as for AL=00h if redirected drive)

See Also: AX=5600h,AX=5601h