IMDSPStorage::GetAttributes method (mswmdm.h)

Article
10/13/2021

The GetAttributes method retrieves the attributes of this storage object.

Syntax

HRESULT GetAttributes(
  [out] DWORD         *pdwAttributes,
  [out] _WAVEFORMATEX *pFormat
);

Parameters

[out] pdwAttributes

Pointer to a DWORD containing the attributes as defined by in the IWMDMStorage::GetAttributes method.

[out] pFormat

Pointer to a _WAVEFORMATEX structure that is filled with attribute information about the object.

Return value

The method returns an HRESULT. All the interface methods in Windows Media Device Manager 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 an extensive list of possible error codes, see Error Codes.

Remarks

Evaluation of attributes is a crucial step when exposing the contents of the media device. Devices may not support hierarchical storage of data on storage media. The GetAttributes method allows the application to infer the support and format of the file system by discovering its structure through object attributes.

For example, the attributes of a top-level IMDSPStorage interface indicate a storage medium, and IMDSPEnumStorage exposes the contents of the medium. For an .mp3 file, the attributes indicate a file whose type can be determined by further examination of both the attributes and the file name. In a hierarchical medium, the attributes can indicate a directory whose contents can be exposed by IMDSPStorage::EnumStorage.

The _WAVEFORMATEX parameter is optional. If you pass a valid _WAVEFORMATEX pointer to an audio file, GetAttributes passes descriptive information back into the structure. However, if the file is not audio, the _WAVEFORMATEX parameter is ignored.

This method must be implemented. It must not return WMDM_E_NOTSUPPORTED or E_NOTIMPL. For more information, see Mandatory and Optional Interfaces.

Requirements

Requirement	Value
Target Platform	Windows
Header	mswmdm.h
Library	Mssachlp.lib