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IWMStreamConfig2::GetDataUnitExtensionCount method (wmsdkidl.h)

[The feature associated with this page, Windows Media Format 11 SDK, is a legacy feature. It has been superseded by Source Reader and Sink Writer. Source Reader and Sink Writer have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Source Reader and Sink Writer instead of Windows Media Format 11 SDK, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The GetDataUnitExtensionCount method retrieves the total number of data unit extension systems that have been added to the stream.

Syntax

HRESULT GetDataUnitExtensionCount(
  [out] WORD *pcDataUnitExtensions
);

Parameters

[out] pcDataUnitExtensions

Pointer to a WORD that receives the count of data unit extensions.

Return value

The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Return code Description
S_OK
The method succeeded.
E_INVALIDARG
pcDataUnitExtensions is NULL.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only],Windows Media Format 9 Series SDK, or later versions of the SDK
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header wmsdkidl.h (include Wmsdk.h)
Library Wmvcore.lib; WMStubDRM.lib (if you use DRM)

See also

IWMStreamConfig2 Interface

IWMStreamConfig2::GetDataUnitExtension