Int 21 Fn 4BF1  - Virus - "jerusalem 2" - Installation Check               [v]

   AX = 4BF1h

Return: AX = 1FB4h if resident

See Also: AH=3Fh/BX=FEB0h"VIRUS",AX=4BDDh"VIRUS",AX=4BFEh"VIRUS"