def dedicate_device(self, userid, vaddr, raddr, mode):
        """dedicate device

        :userid: The name of the image obtaining a dedicated device
        :vaddr: The virtual device number of the device
        :raddr: A real device number to be dedicated or attached
                to the specified image
        :mode: Specify a 1 if the virtual device is to be in read-only mode.
               Otherwise, specify a 0.
        """
        # dedicate device to directory entry
        self._dedicate_device(userid, vaddr, raddr, mode)
dedicate device

        :userid: The name of the image obtaining a dedicated device
        :vaddr: The virtual device number of the device
        :raddr: A real device number to be dedicated or attached
                to the specified image
        :mode: Specify a 1 if the virtual device is to be in read-only mode.
               Otherwise, specify a 0.