IWMDMOperation::BeginWrite (deprecated)
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This is preliminary documentation and subject to change.
This topic documents a feature of the Windows Media Device Manager SDK. We recommend that you migrate your application to use the Windows Portable Devices API. For more information, see the Windows Portable Devices SDK.
The BeginWrite method indicates that a "write to device" action is beginning. Windows Media Device Manager only calls this method if the application calls IWMDMStorageControl/2/3::Insert/2/3 and passes in this interface.
Syntax
HRESULT BeginWrite();
Parameters
This method takes no parameters.
Return Values
The application should return one of the following HRESULT values.
| Return code | Description |
| S_OK | The read operation should continue. |
| WMDM_E_USER_CANCELLED | The read operation should be cancelled without finishing. |
| E_FAIL | An unspecified error occurred, and the read operation should be cancelled without finishing. |
If the application returns either E_FAIL or WMDM_E_USER_CANCELLED, Windows Media Device Manager will call the End method to indicate that termination is finished. If the application is using block mode and returns WMDM_E_USER_CANCELLED, then Windows Media Device Manager will return that error to the application.
Remarks
This method is called just before the Windows Media Device Manager calls IWMDMOperation::TransferObjectData to begin writing data to the device.
Example Code
The following C++ code example implements the BeginWrite method and outputs a message when a write-to-device action is beginning.
HRESULT BeginWrite()
{
// TODO: Display the message: "IWMDMOperation event--BeginWrite."
// If the global handle of the destination file is uninitialized, fail.
if (m_File == INVALID_HANDLE_VALUE)
return E_FAIL;
// Global status to let TransferObjectData know what kind of
// operation is happening.
m_OperationStatus = OPERATION_WRITE;
return S_OK;
}
Requirements
Header: Defined in mswmdm.h.
Library: mssachlp.lib
See Also