Int 21 Fn 4000  - Fartbell.exe - Installation Check                        [j]

   AX = 4000h
   BX = 0002h
   CX = 0000h
   DS:DX = 0000h:0000h

Return: CF clear if installed
       AX = CS of resident code
Program: FARTBELL is a joke program by Guenther Thiele which makes various
     noises when programs output a bell

See Also: AX=4001h