# IRsPersistDeltaStream Struct Reference

Inherits IRsPersistStream.

List of all members.

## Public Member Functions
HRESULT | SaveDelta ([in] IStream *pStm,[in] IRsObject *pObj,[in] RtBOOL fClearDirty)
HRESULT | LoadDelta ([in] IRsObject *pObj,[in] IStream *pStm,[in] RtObjFileHeaderInfo *pObjFileHeaderInfo)

## Detailed Description

Purpose of the interface is to allow Node’s data storing/restoring when the system is shutting down/starting. The IRsPersistDeltaStream extend the IRsPersistStream interface with ability to serialize only the object's difference.

See also:
  IRsPersistStream

## Member Function Documentation

HRESULT IRsPersistDeltaStream::SaveDelta | ( | [in] IStream * | pStm,
|  | [in] IRsObject * | pObj,
|  | [in] RtBOOL | fClearDirty |
| ) |  |  |

Called to serialize object that implement this interface as difference from the pObj.

Parameters:

  | pStm | [in] Specify stream to which the difference will be written.
  | pObj | [in] Object from which the difference stream will be written.
  | fClearDirty | [in] Indicates whether to clear the dirty flag after the save is complete. If TRUE, the flag should be cleared. If FALSE, the flag should be left unchanged.

Remarks:
  SaveDelta shouldn't write longer stream than IRsPersistStream::Save method If it is not possible, return S_FALSE and IRsPersistStream.Save method will be called instead.

HRESULT IRsPersistDeltaStream::LoadDelta | ( | [in] IRsObject * | pObj,
|  | [in] IStream * | pStm,
|  | [in] RtObjFileHeaderInfo * | pObjFileHeaderInfo |
| ) |  |  |

Called to get stream that describe difference between object that implement this interface and the pObj.

Parameters:

  | pObj | [in] .
  | pStm | [in] .
  | pObjFileHeaderInfo | [in] .