SwSrvc Fn 0005H: Unhook Notification Chain

 Expects: AX    0005H
          ES:DI address of an SwCallbackInfoRec structure
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 Returns: AX    0000H and CF is clear (NC) if successful
                CF is set (CY) if the switcher does not support this fn.
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    Info: Use this fn before terminating an application which has used
          SwSrvcFn 0004H (hook notification chain).  This stops the task-
          switcher from calling your notification handler.

See Also: Switcher Services and Notifications
          INT 2fH 4bxxH (switcher functions)
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