[This is preliminary documentation and subject to change.]
The IDirectWriterLock interface enables a single writer to obtain exclusive write access to a root storage object opened in direct mode while allowing concurrent access by multiple readers. This single-writer, multiple-reader mode does not require the overhead of making a snapshot copy of the storage for the readers.
Generally, you do not implement this interface unless you are defining a new storage scheme for your system. COM provides a compound file implementation of the IDirectWriterLock interface. For more information on the system-provided implementation, see IDirectWriterLock - Compound File Implementation.
Use this interface to obtain exclusive write access to a storage object in direct mode.
Call IDirectWriterLock::WaitForWriteAccess to obtain exclusive write access to the storage object. Call IDirectWriterLock::ReleaseWriteAccess to release exclusive write access.
IDirectWriterLock::HaveWriteAccess indicates whether the storage is currently locked.
| IUnknown Methods | Description |
|---|---|
| QueryInterface | Returns pointers to supported interfaces. |
| AddRef | Increments the reference count. |
| Release | Decrements the reference count. |
| IDirectWriterLock Method | Description |
|---|---|
| WaitForWriteAccess | Obtains exclusive write access to a storage. |
| ReleaseWriteAccess | Releases the write lock previously obtained. |
| HaveWriteAccess | Indicates whether the write lock has been taken. |
Windows NT: Use version 5.0 or later.
Windows: Unsupported.
Windows CE: Unsupported.
Header: Declared in objidl.h.