IMDSPStorage::CreateStorage method (mswmdm.h)

Article
10/13/2021

The CreateStorage method creates a new storage and returns a pointer to the IMDSPStorage interface on the newly created storage. This method is optional unless dwAttributes is WMDM_FILE_ATTR_FILE. In that case, this method must be implemented and must not return WMDM_E_NOTSUPPORTED or E_NOTIMPL. For more information, see Mandatory and Optional Interfaces.

Syntax

HRESULT CreateStorage(
  [in]  DWORD         dwAttributes,
  [in]  _WAVEFORMATEX *pFormat,
  [in]  LPWSTR        pwszName,
  [out] IMDSPStorage  **ppNewStorage
);

Parameters

[in] dwAttributes

DWORD containing the attributes for the new storage. The following table lists the available storage attributes.

Attribute	Description
WMDM_STORAGECONTROL_INSERTBEFORE	The new storage object will be created in front of the target object.
WMDM_STORAGECONTROL_INSERTAFTER	The new storage object will be created after the target object.
WMDM_STORAGECONTROL_INSERTINTO	The new storage object will be created in the target object folder.
WMDM_STORAGECONTROL_OVERWRITE	If storage with the same name already exists, it will be destroyed and a new storage created.
WMDM_STORAGE_ATTR_FILESYSTEM	This object is the top-level storage medium (for example, a storage card or some other on-board storage.)
WMDM_STORAGE_ATTR_REMOVABLE	This storage medium is removable.
WMDM_STORAGE_ATTR_CANEDITMETADATA	This storage can edit metadata.
WMDM_STORAGE_ATTR_FOLDERS	This storage medium supports folders and file hierarchy.
WMDM_FILE_ATTR_FOLDER	This is a folder on the storage medium.
WMDM_FILE_ATTR_LINK	This is a link that creates an association among multiple files.
WMDM_FILE_ATTR_FILE	This is a file on the storage medium.
WMDM_FILE_ATTR_AUDIO	This file is audio data.
WMDM_FILE_ATTR_DATA	This file is non-audio data.
WMDM_FILE_ATTR_CANPLAY	This audio file can be played by the device.
WMDM_FILE_ATTR_CANDELETE	This file can be deleted.
WMDM_FILE_ATTR_CANMOVE	This file or folder can be moved around on the storage medium.
WMDM_FILE_ATTR_CANRENAME	This file or folder can be renamed.
WMDM_FILE_ATTR_CANREAD	This file can be read by the host computer.
WMDM_FILE_ATTR_MUSIC	This audio file is music.
WMDM_FILE_ATTR_VIDEO	This file contains video data.
WMDM_FILE_ATTR_HIDDEN	This file is hidden on the file system
WMDM_FILE_ATTR_SYSTEM	This is a system file
WMDM_FILE_ATTR_READONLY	This is a read-only file.
WMDM_STORAGE_IS_DEFAULT	This storage is the default storage where new media should be placed.
WMDM_STORAGE_CONTAINS_DEFAULT	This storage contains the default storage where new media should be placed.

[in] pFormat

Pointer to a _WAVEFORMATEX structure that contains information about the object, if the object is an audio file.

[in] pwszName

Pointer to a wide-character null-terminated string containing the name for the new storage.

[out] ppNewStorage

Pointer to an IMDSPStorage pointer to receive the IMDSPStorage interface for the newly created storage.

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

If both the WMDM_FILE_ATTR_FOLDER and WMDM_FILE_ATTR_FILE attributes are set, the folder attribute overrides the file attribute, and the new storage is created as a folder.

Only one of WMDM_STORAGECONTROL_INSERTBEFORE, WMDM_STORAGECONTROL_INSERTAFTER, and WMDM_STORAGECONTROL_INSERTINTO can be specified by the client.

The new storage can be created at the same level or can be inserted into the current storage provided that the current storage is a folder. This is controlled by the value of dwAttributes parameter. If it specifies WMDM_STORAGECONTROL_INSERTBEFORE or WMDM_STORAGECONTROL_INSERTAFTER, the new storage will be created at the same level as the current storage. If it specifies WMDM_STORAGECONTROL_INSERTINTO, the new storage will be inserted into the current storage.

WMDM_STORAGECONTROL_INSERTBEFORE and WMDM_STORAGECONTROL_INSERAFTER imply an ordering of content in the file system. If the file system does not support ordering (for example, FAT32) both the flags have the identical effect of inserting the new storage at the same level of the current storage. If the current storage represents the root of the storage medium, and one of these two flags is specified, the operation fails.

WMDM_STORAGECONTROL_INSERTINTO is valid only if the current storage is a folder. If the current storage is a file, and this flag is specified, the operation fails.

Requirements

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