DBLSPACE

Type: External (6.0 and later)

Syntax:

DBLSPACE
DBLSPACE / automount=drives
DBLSPACE /chkdsk [/F] [d:]
DBLSPACE /compress d: [/newdrive=host:] [/reserve=size] [/F]
DBLSPACE /create d: [/newdrive=host:] [/reserve=size] [/size=size]
DBLSPACE /defragment [d:] ]/F]
DBLSPACE /delete d:
DBLSPACE /doubleguard=0|1
DBLSPACE /format d:
DBLSPACE [/info] [d:]
DBLSPACE /list
DBLSPACE /mount[=nnn] host: [/newdrive=d:]
DBLSPACE /ratio[=ratio] [d:] [/all]
DBLSPACE /size[=size] [/reserve=size] d:
DBLSPACE /uncompress d:
DBLSPACE /unmount [d:]

Purpose: DBLSPACE is a disk compression utility that is included with DOS, beginning with Version 6. It provides a way to increase disk capacity by compressing the data on all or part of a disk.

Discussion

To start the full-screen interface of the DBLSPACE disk-compression program you enter

dblspace

by itself on the command line. Then, you control each individual aspect of the DBLSPACE program by entering options and parameters at the DOS command line. The sections that follow describe each of the DBLSPACE options that are available.



NOTE:
Some versions of DOS 6 may not include the DBLSPACE program. In addition, it has been reported that the use of the DBLSPACE program that was first included in DOS Version 6 can result in data storage errors, especially when DBLSPACE is used in combination with the SMARTDrive program. However, it has also been reported that these problems were fixed in the 6.2 version of DOS. Some versions of DOS may include other methods of compressing stored data.


Option 1. DBLSPACE / AUTOMOUNT

Syntax:

DBLSPACE / automount=drive

Enables or disables automatic mounting of removable drives. The default is for automatic mounting of removable drives. You cannot use this command while Windows is running.

Option

drives - Specifies the removable drives that you want DBLSPACE to automatically mount.


Option 2. DBLSPACE / CHKDSK

Syntax:

DBLSPACE /chkdsk [/F] [d:]

Tells DBLSPACE to check the structure of a compressed drive and report any errors found. Using the /F option will cause DBLSPACE to attempt to fix found errors. (This option is not available with DOS 6.2. You should use the SCANDISK utility instead.)

Option

/F - Tells DBLSPACE to repair any errors that it finds.


Option 3. DBLSPACE / COMPRESS

Syntax:

DBLSPACE /compress d: [/newdrive=host:] [/reserve=size] [/F]
Used to compress the files on an existing hard disk, floppy disk, or other removable disk.

Options

/newdrive=host - Specifies the uncompressed host drive after compression. If not specified, the next available drive letter will be used. (You can abbreviate newdrive as new.)

/reserve=size - Specifies the amount of space to be left uncompressed on the host drive. The default for hard disks is 2M and for floppy disks, 0.

/F - Causes DBLSPACE to return to the DOS command prompt when compression is finished rather than displaying compression statistics.


Option 4. DBLSPACE / CREATE

Syntax:

DBLSPACE /create d: [/newdrive=host:] [/reserve=size] [/size=size]

Creates a new compressed drive by using free space on an uncompressed drive. This option can only be used on nonremovable drives.

Options

/newdrive=host - The new compressed drive. The default is the next available letter.

/reserve=size - Specifies the amount of space to be left uncompressed on the host drive. If you omit both the /reserve and size options , 1M of uncompressed space will be reserved on your disk. You cannot use the /SIZE and /RESERVE options at the same time.

/size=size - Specifies the size of the compressed volume file that will be created on the host drive. You cannot use the /SIZE and /RESERVE options at the same time.


Option 5. DBLSPACE / DEFRAGMENT

Syntax:

DBLSPACE /defragment [d:] ]/F]

Used to defragment a compressed drive. This is accomplished by moving all of the drive`s free space to the end of the drive. To stop the defragmenting process, press the Esc key.

Option

/F - Tells DBLSPACE to defragment the drive more completely.


Option 6. DBLSPACE / DELETE

Syntax:

DBLSPACE /delete d:

Used to unmount a compressed drive and delete its compressed volume file from the host drive. To delete all the files on a compressed drive, it is better to use the DBLSPACE/FORMAT option.


Option 7. DBLSPACE / DOUBLEGUARD

Syntax:

DBLSPACE /doubleguard=0|1

The Doubleguard option monitors the integrity of the memory being used by DBLSPACE to minimize memory corruption. Restart your computer after using the Doubleguard option.

Option

0|1 0 disables DoubleGuard and 1 enables it.


Option 8. DBLSPACE / FORMAT

Syntax:

DBLSPACE /format d:

Used to delete all files and subdirectories on a compressed drive, leaving the drive intact.


Option 9. DBLSPACE / INFO

Syntax:

DBLSPACE [/info] [d:]

Used to display information about a specified compressed drive including, it`s host drive, used and free space, actual and estimated compression ratio, and the total size.

Option

/info - If you do use this option without specifying a drive the current drive will be assumed.


Option 10. DBLSPACE / LIST

Syntax:

DBLSPACE /list

Used to display information about all the compressed and uncompressed local drives connected to your computer. The letter, type, free space, total size and CVF files name are displayed for each drive. Information will not be displayed for networks and CD-ROM drives.


Option 11. DBLSPACE / MOUNT

Syntax:

DBLSPACE /mount[=nnn] host: [/newdrive=d:]

Tells DBLSPACE to associate a drive letter with a compressed volume file (CVF) so that files in the CVF can be accessed as if they were on a disk.

Options

=nnn - Used to mount the CVF named DBLSPACE.nnn on the host drive. The default is DBLSPACE.000.

host: Specifies the uncompressed host drive that contains the CVF you want to access.

/newdrive=d: - Used if you are mounting a CVF file created with the /COMPRESS option (nnn=000). d: is the drive letter you want to use for the host drive after the CVF is mounted. When mounting a CVF created with the /CREATE option (nnn>000), d: is the drive letter you want to use for the compressed drive after the CVF file is mounted.


Option 12. DBLSPACE / RATIO

Syntax:

DBLSPACE /ratio[=ratio] [d:] [/all]

Determines the estimated compression ratio that DBLSPACE will use when compressing a drive. Options

=ratio - Specifies the new estimated compression ratio (from 1.0 to 16.0). This number must be entered with one decimal place.

/all - Used to change the estimated compression ratios for all mounted compressed drives.


Option 13. DBLSPACE / SIZE

Syntax:

DBLSPACE /size[=size] [/reserve=size] d:

Used to change the size of a compressed drive.

Options

=size - Specifies the space that the CVF on the specified drive should take up on its uncompressed host drive.

/reserve=size - Specifies the amount of free space to be left on the uncompressed host drive are the specified drive is resized. You cannot use both =size and /RESERVE=size at the same time.

d: - Specifies the compressed drive for which you want to change the size.


Option 14. DBLSPACE / UNCOMPRESS

Syntax:

DBLSPACE /uncompress d:

Used to uncompress a drive previously compressed with DBLSPACE. Once you have removed all compressed drives, DBLSPACE will be removed from memory.


Option 15. DBLSPACE / UNMOUNT

Syntax:

DBLSPACE /unmount [d:]

Used to break the association between a drive letter and a compressed volume file (CVF). This will make the compressed drive temporarily unavailable.




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