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  · DriverStudio          Obtaining Plug and Play Hardware IDs in Windows 95
  · DriverBundle          and WDM Drivers
  · Previews
  · Compatibility         In a Plug and Play environment, the operating system
 [Downloads]  ·           detects the presence of a device and notifies the
                          driver responsible for controlling it. For Win32
 Wizards                  Driver Model (WDM) drivers, the operating system
  · Utilities             notifies the driver by calling the driver's AddDevice
  · NT source             entry point. For VxDs in Windows 95 and Windows 98,
 examples                 notification is in the form of a control message,
  · VxD source            namely PNP_NEWDEVNODE.
 examples
  · WDM source            If a driver supports more than one device, and it
 examples                 does not handle all devices in the same way, then it
 [Resources]  ·           needs to determine which of the physical devices
 Technical papers         under its control corresponds to a notification sent
  · Useful links          by the operating system. Since the operating system
  · Technical tips        assigns a unique Hardware ID to each device, one way
 [Support]  ·             for the driver to identify a device is by its
                          Hardware ID.
 Support
  · Knowledge base        WDM
  · Problem               A WDM driver can obtain the Hardware ID of a device
 submission               using the Physical Device Object (PDO) pointer that
  · Product               the system passes as a parameter to AddDevice. A WDM
 registration             driver calls the system service IoGetDeviceProperty
  · Release notes         as follows:
 [Shop NuMega]  ·
 Buy it!                      NTSTATUS status;
  · Price list                ULONG ReqLen;
  · How to buy                USHORT HardwareID[MAX_ID_SIZE];
  · Sales offices             status =IoGetDeviceProperty(
                                  PDO,
                                  DevicePropertyHardwareID,
 [Y2K Compliance]                 sizeof(HardwareID),
                                  HardwareID,
                                  &ReqLen
 [More information]               );

                          IoGetDeviceProperty writes the device's hardware IDs
                          into the provided buffer. Compatible ID strings are
                          delimited by commas. If the provided buffer is too
                          small, the service returns STATUS_BUFFER_OVERFLOW.
                          Since the buffer may have to be quite large, it is a
                          good idea to allocate it temporarily from the paged
                          pool, and release it when no longer needed.

                          A WDM driver built with DriverWorks can just call
                          member GetHardwareID of class KPnpLowerDevice.

                          VxD
                          A VxD makes an analogous call to the Configuration
                          Manager, passing the DevNode rather than a PDO
                          (assuming VtoolsD):

                              CONFIGRET status;
                              ULONG ReqLen;
                              USHORT HardwareID[MAX_ID_SIZE];
                              status =CONFIGMG_Get_Device_ID(
                                  DevNode,
                                  HardwareID,
                                  sizeof(HardwareID),
                                  0
                                  );

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