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IWMDMProgress::Progress

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The Progress method indicates that an operation is still in progress.

Syntax

HRESULT Progress(
  DWORD  dwTranspiredTicks
);

Parameters

dwTranspiredTicks

[in]  DWORD containing the number of ticks that have transpired so far.

Return Values

The method returns an HRESULT. All the interface methods in Windows Media Device Manager and service provider can return any of the following classes of error codes:

  • Standard COM error codes
  • Windows error codes converted to HRESULT values
  • Windows Media Device Manager error codes

For a complete list of possible error codes, see Error Codes.

Possible values include, but are not limited to, those in the following table.

Return code Description
S_OK The method succeeded.
WMDM_E_USER_CANCELLED The application instructs Windows Media Device Manager to cancel the current operation without waiting for it to finish.
E_FAIL An unspecified error occurred.

Remarks

The interface that owns the method that is implementing an operation calls the Progress method as the operation defined by the method is carried out. The intention is that Progress will be called once per estimated tick. However, the dwTranspiredTicks parameter must be checked on each call because the operation being performed may not guarantee a call once for each estimated tick.

The application returns S_OK to the calling method to indicate that the operation should continue. The application returns WMDM_E_USER_CANCELLED to indicate that the operation should be cancelled. If the application is using block mode and returns WMDM_E_USER_CANCELLED, then Windows Media Device Manager will return this same error to the application.

Requirements

Header: Defined in wmdm.idl.

Library: mssachlp.lib

See Also