IStream::Commit
Ensures that
any changes made to a stream object open in transacted mode are reflected in
the parent storage. If the stream object is open in direct mode, IStream::Commit
has no effect other than flushing all memory buffers to the next level storage
object. The OLE compound file implementation of streams does not support
opening streams in transacted mode.
HRESULT Commit(
|
DWORD grfCommitFlags |
//Specifies
how changes are committed |
|
); |
|
Parameter
grfCommitFlags
[in] Controls
how the changes for the stream object are committed. See the STGC enumeration for a
definition of these values.
Return Values
S_OK
Changes to
the stream object were successfully committed to the parent level.
E_PENDING
Asynchronous
Storage only: Part or all of the stream s
data is currently unavailable. For more information see IFillLockBytes and Asynchronous
Storage.
STG_E_MEDIUMFULL
The commit
operation failed due to lack of space on the storage device.
STG_E_REVERTED
The object
has been invalidated by a revert operation above it in the transaction tree.
Remarks
This method
ensures that changes to a stream object opened in transacted mode are reflected
in the parent storage. Changes that have been made to the stream since it was
opened or last committed are reflected to the parent storage object. If the
parent is opened in transacted mode, the parent may still revert at a later
time rolling back the changes to this stream object. The compound file
implementation does not support opening streams in transacted mode, so this
method has very little effect other than to flush memory buffers. For more
information, refer to IStream - Compound File Implementation.
If the stream
is open in direct mode, this method ensures that any memory buffers have been flushed
out to the underlying storage object. This is much like a flush in traditional
file systems.
The IStream::Commit
method is useful on a direct mode stream when the implementation of the IStream interface is a wrapper for
underlying file system APIs. In this case, IStream::Commit would be
connected to the file system s flush call.
See Also
IStream
- Compound File Implementation, IStorage::Commit