MFBeginCreateFile function (mfapi.h)

Begins an asynchronous request to create a byte stream from a file.

Syntax

HRESULT MFBeginCreateFile(
  [in]  MF_FILE_ACCESSMODE AccessMode,
  [in]  MF_FILE_OPENMODE   OpenMode,
  [in]  MF_FILE_FLAGS      fFlags,
  [in]  LPCWSTR            pwszFilePath,
  [in]  IMFAsyncCallback   *pCallback,
  [in]  IUnknown           *pState,
  [out] IUnknown           **ppCancelCookie
);

Parameters

[in] AccessMode

The requested access mode, specified as a member of the MF_FILE_ACCESSMODE enumeration.

[in] OpenMode

The behavior of the function if the file already exists or does not exist, specified as a member of the MF_FILE_OPENMODE enumeration.

[in] fFlags

Bitwise OR of values from the MF_FILE_FLAGS enumeration.

[in] pwszFilePath

Pointer to a null-terminated string containing the file name.

[in] pCallback

Pointer to the IMFAsyncCallback interface of a callback object. The caller must implement this interface

[in] pState

Pointer to the IUnknown interface of a state object, defined by the caller. This parameter can be NULL. You can use this object to hold state information. The object is returned to the caller when the callback is invoked.

[out] ppCancelCookie

Receives an IUnknown pointer or the value NULL. If the value is not NULL, you can cancel the asynchronous operation by passing this pointer to the MFCancelCreateFile function. The caller must release the interface. This parameter is optional and can be NULL.

Return value

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

Return code Description
S_OK
The function succeeded.

Remarks

When the request is completed, the callback object's IMFAsyncCallback::Invoke method is called. The callback object should then call the MFEndCreateFile function to get a pointer to the byte stream.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Target Platform Windows
Header mfapi.h
Library Mfplat.lib
DLL Mfplat.dll

See also

Media Foundation Functions