EWF API Functions

The following table describes the EWF creation and configuration function.

Function Description
ConfigureEwf This function creates and configures the EWF volume on the device.

The following table shows the functions that are used to query and configure protected Enhanced Write Filter (EWF) volumes.

Function Description
EwfMgrGetDriveLetterFromVolumeName This function gets the drive letter for the specified volume name.
EwfMgrOpenProtected This function opens an EWF-protected volume.
EwfMgrClose This function closes an EWF-protected volume.
EwfMgrClearCommand This function clears any pending commands that would have occurred on the next restart.
EwfMgrSetPersistentData This function sets the persistent data for an EWF-protected volume.
EwfMgrGetPersistentData This function gets the persistent data for an EWF-protected volume.
EwfMgrCheckpoint This function adds a checkpoint overlay level on the specified EWF-protected volume.
EwfMgrRestore This function restores one overlay level on the specified EWF-protected volume, discarding all changes in the current level.
EwfMgrDisable This function disables a currently enabled overlay on the specified EWF-protected volume.
EwfMgrEnable This function enables a currently disabled overlay on the specified EWF-protected volume.
EwfMgrCommit This function commits all current level data in the overlay to the EWF-protected volume.
EwfMgrCommitFile This function commits a single file to the protected volume. The size of the file or its location must not have changed before the file is committed.
EwfMgrCommitAndDisableLive This function immediately commits all current level data to the EWF-protected volume and then disabled EWF. This function does not require a reboot.
EwfMgrSetLevel This function sets the overlay level on an EWF-protected volume.
EwfMgrGetProtectedVolumeConfig This function gets the configuration information for an EWF-protected volume.

The following table shows the functions that are used to query and configure the EWF overlay store volumes.

Function Description
EwfMgrOpenOverlayStore This function gets the name of the overlay store volume, if it exists.
EwfMgrGetOverlayStoreConfig This function gets the configuration information for the EWF overlay store.
EwfMgrRegisterLowSpaceNotification This function registers for a low space notification when the available bytes in the overlay reach a specified threshold.

The following table shows the functions that are used to obtain and work with a list of EWF-protected volumes.

Function Description
EwfMgrGetProtectedVolumeList This function gets a list of all the EWF-protected volumes.
EwfMgrVolumeNameListIsEmpty This function determines if the EWF volume name list is empty.
EwfMgrVolumeNameEntryPop This function removes the current entry from the EWF volume name list and frees the current memory entry.
EwfMgrVolumeNameListDelete This function deletes all entries in the EWF volume name list.

The following table shows the functions that are used to manage Hibernate Once Resume Many (HORM).

Function Description
EwfMgrActivateHorm Enables HORM support at run-time
EwfMgrDeactivateHorm Disables HORM support
EwfMgrIsHormActivated Returns the current status of HORM

See Also

Enhanced Write Filter API | EWF API Code Sample

Last updated on Wednesday, October 18, 2006

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