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IMFDXGIDeviceManager::LockDevice method (mfobjects.h)

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Gives the caller exclusive access to the Microsoft Direct3D device.

Syntax

HRESULT LockDevice(
  [in]  HANDLE hDevice,
  [in]  REFIID riid,
  [out] void   **ppUnkDevice,
  [in]  BOOL   fBlock
);

Parameters

[in] hDevice

A handle to the Direct3D device. To get the device handle, call IMFDXGIDeviceManager::OpenDeviceHandle.

[in] riid

The interface identifier (IID) of the requested interface. The Direct3D device will support the following interfaces:

[out] ppUnkDevice

Receives a pointer to the requested interface. The caller must release the interface.

[in] fBlock

Specifies whether to wait for the device lock. If the device is already locked and this parameter is TRUE, the method blocks until the device is unlocked. Otherwise, if the device is locked and this parameter is FALSE, the method returns immediately with the error code DXVA2_E_VIDEO_DEVICE_LOCKED.

Return value

This method can return one of these values.

Return code Description
S_OK
 Success.
E_HANDLE
 The specified handle is not a Direct3D device handle.
MF_E_DXGI_DEVICE_NOT_INITIALIZED
 The DXGI Device Manager was not initialized. The owner of the device must call IMFDXGIDeviceManager::ResetDevice.
MF_E_DXGI_NEW_VIDEO_DEVICE
 The device handle is invalid.
MF_E_DXGI_VIDEO_DEVICE_LOCKED
 The device is locked and fBlock is FALSE.

Remarks

When you are done using the Direct3D device, call IMFDXGIDeviceManager::UnlockDevice to unlock the device.

If the method returns MF_E_DXGI_NEW_VIDEO_DEVICE, call IMFDXGIDeviceManager::CloseDeviceHandle to close the handle and then call OpenDeviceHandle again to get a new handle. The IMFDXGIDeviceManager::ResetDevice method invalidates all open device handles.

If fBlock is TRUE, this method can potentially deadlock. For example, it will deadlock if a thread calls LockDevice and then waits on another thread that calls LockDevice. It will also deadlock if a thread calls LockDevice twice without calling UnlockDevice in between.

Requirements

Requirement Value
Minimum supported client Windows 8 [desktop apps | UWP apps]
Minimum supported server Windows Server 2012 [desktop apps | UWP apps]
Target Platform Windows
Header mfobjects.h (include Mfidl.h)

See also

IMFDXGIDeviceManager