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IWMStreamList::GetStreams 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 It has been superseded by Source Reader and Sink Writer.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 GetStreams method retrieves an array of stream numbers that make up the list.

Syntax

HRESULT GetStreams(
  [out]     WORD *pwStreamNumArray,
  [in, out] WORD *pcStreams
);

Parameters

[out] pwStreamNumArray

Pointer to a WORD array containing the stream numbers. Pass NULL to retrieve the required size of the array.

[in, out] pcStreams

On input, a pointer to a variable containing the size of the pwStreamNumArray array. On output, if the method succeeds, this variable contains the number of stream numbers entered into pwStreamNumArray by the method.

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_POINTER
The pcStreams parameter is NULL.
ASF_E_BUFFERTOOSMALL
The input value of pcStreams is not large enough.

Remarks

You should make two calls to GetStreams. On the first call, pass NULL as pwStreamNumArray. On return, the value pointed to by pcStreams is set to the number of stream numbers in the stream number array. Then you can allocate the required amount of memory for the array and pass a pointer to it as pwStreamNumArray on the second call.

Stream numbers are in the range of 1 through 63.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only],Windows Media Format 7 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

IWMStreamList Interface