Int 16 Fn FFC5  U - PC Tools V5.1-8.0 Desktop - Check Whether Desktop Loa  [U]

   AX = FFC5h

Return: BL = nonzero if loaded resident
      = 00h if nonresident

Note:  available only when popped up; should call AX=FFEFh first to ensure
     that DESKTOP is active

See Also: AX=FFEFh,AX=FFF3h