EWF API Functions

5/10/2007

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

Concepts

Enhanced Write Filter API
EWF API Code Sample