ICAT::GetTableDescriptorByTag method (mpeg2psiparser.h)

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This topic applies to Update Rollup 2 for Microsoft Windows XP Media Center Edition 2005 and later.

The GetTableDescriptorByTag method searches the CAT for a descriptor with the specified descriptor tag.

Syntax

HRESULT GetTableDescriptorByTag(
  [in]      BYTE               bTag,
  [in, out] DWORD              *pdwCookie,
  [out]     IGenericDescriptor **ppDescriptor
);

Parameters

[in] bTag

Specifies the descriptor tag for which to search.

[in, out] pdwCookie

Pointer to a variable that specifies the start position in the descriptor list. This parameter is optional. If the value of pdwCookie is NULL, the search starts from the first descriptor in the list. Otherwise, the search starts from the position given in pdwCookie. When the method returns, the pdwCookie parameter contains the position of the next matching descriptor, if any. You can use this parameter to iterate through the descriptor list, looking for every instance of a particular descriptor tag.

[out] ppDescriptor

Receives a pointer to the IGenericDescriptor interface. Use this interface to retrieve the information in the descriptor. The caller must release the interface.

Return value

The method returns an HRESULT. Possible values include those in the following table.

Remarks

If the value of pdwCookie is not NULL, the method returns either MPEG2_S_NO_MORE_DATA_AVAILABLE or MPEG2_S_MORE_DATA_AVAILABLE to indicate whether the MGT contains additional tags that match the search criteria.

Requirements

See also

ICAT Interface