[This is preliminary documentation and subject to change.]
IPersistStream is a standard interface for saving and restoring the state of an object. Each filter, when created, may receive an IStream from which to initialize itself. Announcement Listener uses this interface to request filters to save their states into a different IStream on shutdown, and to restore their states from that IStream on start-up.
At a minimum, a filter must save the number of announcements it has matched, and the date of the last announcement it matched. Any other state persistence is entirely at the option of the filter.
To locate more information on the IPersistStream interface, see Further Information on Data Services for the Client.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in objidl.h.