FBWF Manager (Standard 8)

7/8/2014

Review the use, syntax, options, and parameters of File-Based Write Filter Manager for Windows Embedded 8 Standard (Standard 8).

FBWF Manager is a command-line tool that is included in Windows Embedded 8 Standard (Standard 8) to quickly integrate and prototype the File-Based Write Filter (FBWF). FBWF Manager is intended primarily for design-time use, but it can also be used to configure FBWF at run time.

FBWF Manager Command-Line Syntax

FBWF Manager command-line syntax follows:

fbwfmgr  [ /? | /help /[switch] | /displayconfig |
 /overlaydetail | /enable | /disable | /addvolume [volumename] |
 /removevolume [volumename] [1|0] |
 /addexclusion [volumename] [file or directory path] |
 /removeexclusion [volumename] [file or directory path] |
 /setthreshold [threshold] | /setcompression [1|0] |
 /setpreallocation [1|0] | /commit [volumename] [file path] |
 /restore [volumename] [file path] | /setsizedisplay [1|0] |
 /getvirtualsize [volumename] | /getactualsize [volumename]

The following table describes the command-line switches.

Switch

Description

?

Displays usage and help.

addexclusion

Adds a write-through path of the exclusion list for the next restart.

volumename

The volume name can be either a drive letter (for example, C), a device name (for example, \Device\Harddiskvolume), or a volume GUID path in the form of "\\?\Volume{<GUID>}\" where <GUID> identifies the volume (for example, \\?\Volume{26a21bda-a627-11d7-9931-806e6f6e6963}\).

Referencing volumes by using GUIDs is more reliable because you avoid factors that make it difficult to identify a volume. For example, two volumes may have the same label, a volume might not have a drive letter or label, and drive letters may change as volumes are added to and removed from the computer. For more information, see Naming a Volume. To retrieve the GUID volume path for a volume, see the GetVolumeNameForVolumeMountPoint Function.

Notice that the name is not the volume label that Windows Explorer displays before the drive letter.

addvolume

Adds a volume to the protected volume list for the next restart.

commit

Commits the changes that you made to the file to the underlying media.

The volume name can be either a drive letter (for example, C), a device name (for example, \Device\Harddiskvolume), or a volume GUID path in the form of "\\?\Volume{<GUID>}\" where <GUID> identifies the volume (for example, \\?\Volume{26a21bda-a627-11d7-9931-806e6f6e6963}\).

Referencing volumes by using GUIDs is more reliable because you avoid factors that make it difficult to identify a volume. For example, two volumes may have the same label, a volume might not have a drive letter or label, and drive letters may change as volumes are added to and removed from the computer. For more information, see Naming a Volume. To retrieve the GUID volume path for a volume, see the GetVolumeNameForVolumeMountPoint Function.

Notice that the volume must currently be protected. Otherwise, the following error message appears: "The system cannot find the drive specified."

disable

Disables the write filter on the next restart.

displayconfig

Displays all configuration information for the write filter including a protected volumes list, the overlay configuration, and write-through paths. The command returns:

  • State - Indicates current filter state (enabled or disabled) and state for the next restart.
  • Protected Volumes - List of protected volumes including the current and the next restart state.
  • Compression - Current and next restart state for cache compression.
  • Threshold - Current and next restart values for the overlay cache threshold.
  • Write-Through Paths - Displays a complete list of active and next restart write-through paths.
  • Preallocation Status - Displays current and next restart status for cache preallocation.

enable

Enables the write filter on the next restart.

getactualsize

Displays the actual volume disk size information.

getvirtualsize

Displays the virtual volume disk size information.

help / [switch]

Displays help information for a specific FBWF Manager switch.

overlaydetail

Displays details on the current overlay contents for all protected volumes. The command returns:

  • Contents - Files and folders currently in the overlay for all protected volumes including sizes (size of data in overlay) and open file handles.
  • Memory Usage - Total amount of memory being consumed by the overlay.

removeexclusion

Removes a write-through path from the exclusion list for next restart.

The volume name can be either a drive letter (for example, C), a device name (for example, \Device\Harddiskvolume), or a volume GUID path in the form of "\\?\Volume{<GUID>}\" where <GUID> identifies the volume (for example, \\?\Volume{26a21bda-a627-11d7-9931-806e6f6e6963}\).

Referencing volumes by using GUIDs is more reliable because you avoid factors that make it difficult to identify a volume. For example, two volumes may have the same label, a volume might not have a drive letter or label, and drive letters may change as volumes are added to and removed from the computer. For more information, see Naming a Volume. To retrieve the GUID volume path for a volume, see the GetVolumeNameForVolumeMountPoint Function.

Notice that the name is not the volume label that Windows Explorer displays before the drive letter.

removevolume

Removes a volume from the protected volume list for next restart and either preserves the exclusion list (0) or removes it (1).

restore

Discards the changes that you made to the file; that is, it restores the files to its original contents from the underlying media.

The volume name can be either a drive letter (for example, C), a device name (for example, \Device\Harddiskvolume), or a volume GUID path in the form of "\\?\Volume{<GUID>}\" where <GUID> identifies the volume (for example, \\?\Volume{26a21bda-a627-11d7-9931-806e6f6e6963}\).

Referencing volumes by using GUIDs is more reliable because you avoid factors that make it difficult to identify a volume. For example, two volumes may have the same label, a volume might not have a drive letter or label, and drive letters may change as volumes are added to and removed from the computer. For more information, see Naming a Volume. To retrieve the GUID volume path for a volume, see the GetVolumeNameForVolumeMountPoint Function.

Notice that the name is not the volume label that Windows Explorer displays before the drive letter.

Any change to a file can be discarded, including deletion of the file. In this case, it is recovered.

Notice that the volume must currently be protected. Otherwise, following error message appears: "The system cannot find the drive specified."

setcompression

Sets overlay compression as enabled (1) or disabled (0) for the next restart.

setpreallocation

Sets cache preallocation as enabled (1) or disabled (0) for the next restart.

setsizedisplay

Sets the size display mode to either virtual (1) or actual (0). The new mode takes effect after the next restart.

setthreshold

Sets the overlay threshold value for the next restart. The input field threshold is the overlay threshold in megabytes.

If no switch is provided, FBWF Manager displays all the configuration information, exactly as the displayConfig switch.

FBWF APIs are provided for comprehensive management and configuration of devices in the field.

FBWF does not resolve substituted paths. Use complete file names instead.

See Also

Concepts

File-Based Write Filter Reference
FBWF API
Configure FBWF at Run Time