IPersistStorage::HandsOffStorage

A version of this page is also available for

Windows Embedded CE 6.0 R3

4/8/2010

This method instructs the object to release all storage objects that have been passed to it by its container and to enter HandsOff mode, in which the object cannot do anything and only the close operation works.

Syntax

HRESULT HandsOfStorage(void);

Parameters

None.

Return Value

S_OK indicates that the object has successfully entered HandsOff mode.

Remarks

This method causes an object to release any storage objects that it is holding and to enter the HandsOff mode until a subsequent IPersistStorage::SaveCompleted call. In HandsOff mode, the object cannot do anything and the only operation that works is a close operation.

A container application typically calls this method during a full save or low-memory full save operation to force the object to release all pointers to its current storage.

In these scenarios, the HandsOffStorage call comes after a call to either the OleSave function or the IPersistStorage::Save method, putting the object in HandsOffAfterSave mode.

Calling this method is necessary so the container application can delete the current file as part of a full save, or so it can call the IRootStorage::SwitchToFile method as part of a low-memory save.

A container application also calls this method when an object is in Normal mode to put the object in HandsOffFromNormal mode.

While the component object is in either HandsOffAfterSave or HandsOffFromNormal mode, most operations on the object will fail. Thus, the container should restore the object to Normal mode as soon as possible.

The container application does this by calling the IPersistStorage::SaveCompleted method, which passes a storage pointer back to the component object for the new storage object.

To determine whether the platform supports this interface, see Determining Supported COM APIs.

Notes to Implementers

This method must release all pointers to the current storage object, including pointers to any nested streams and storages.

If the object contains nested objects, the container application must recursively call this method for any nested objects that are loaded or running.

Requirements

See Also

Reference

OleSave
IPersistStorage::Save
IPersistStorage::SaveCompleted
IRootStorage::SwitchToFile