----------------------- MS-DOS v6.22 Help: DRVSPACE ------------------------
<Notes>                                                            <Index>


Compresses hard disk drives or floppy disks, and configures drives that were
compressed by using DriveSpace.


When you issue the DRVSPACE command by itself, the DriveSpace program
starts. This program provides an easy-to-use, menu-oriented user interface
for setting up and working with compressed drives. For more information, see
"Freeing Disk Space by Using DriveSpace" in the Microsoft MS-DOS User's
Guide or Microsoft MS-DOS User's Guide Addendum. For tips on using
DriveSpace, see <DriveSpace Tips>.

If you add switches or parameters to the DRVSPACE command, MS-DOS carries
out the requested task without starting the DriveSpace program. The command
syntax differs from task to task. You can use the DRVSPACE command to
perform the following tasks:

*  Compress a hard disk drive or floppy disk. For more information, see

*  Create a new compressed drive in the free space on an existing drive. For
   more information, see <DRVSPACE /CREATE>.

*  Defragment a compressed drive. For more information, see

*  Delete a compressed drive. For more information, see <DRVSPACE /DELETE>.

*  Format a compressed drive. For more information, see <DRVSPACE /FORMAT>.

*  Display information about a compressed drive. For more information, see

*  Display a list of the drives on your computer. The list includes
   compressed and uncompressed hard disk drives, floppy disk drives, and
   other removable-media drives. It does not include network drives. For
   more information, see <DRVSPACE /LIST>.

*  Mount a compressed volume file (CVF). When DriveSpace mounts a CVF, it
   assigns it a drive letter; you can then use the files that CVF contains.
   For more information, see <DRVSPACE /MOUNT>.

*  Change the estimated compression ratio of a compressed drive. For more
   information, see <DRVSPACE /RATIO>.

*  Change the size of a compressed drive. For more information, see

*  Uncompress a compressed drive. For more information, see

*  Unmount a compressed drive. For more information, see

*  Change the settings in your DRVSPACE.INI file. For more information, see




Fixing problems with drives compressed using DriveSpace

To repair disk problems, use the ScanDisk program, a full-featured disk
analysis and repair utility. ScanDisk can check and repair both compressed
and uncompressed drives. It can even check and repair unmounted DriveSpace
compressed volume files. For more information, see <SCANDISK>.

Running the DRVSPACE command without switches or parameters

The first time you run the DRVSPACE command, it starts the DriveSpace Setup
program. DriveSpace Setup compresses your hard disk drive and loads
DRVSPACE.BIN into memory. DRVSPACE.BIN is the part of MS-DOS that provides
access to compressed drives.

Thereafter, when you run the DRVSPACE command without specifying any
switches or parameters, the DriveSpace program starts. This program lists
your compressed drives and provides menu commands for working with them. You
can perform all DriveSpace tasks either from within the DriveSpace program
or from the MS-DOS command line.


DRVSPACE.BIN is the part of MS-DOS that provides access to your compressed
drives. When you start your computer, MS-DOS loads DRVSPACE.BIN along with
other operating system functions, before carrying out the commands in your
CONFIG.SYS and AUTOEXEC.BAT files. DRVSPACE.BIN initially loads in
conventional memory, since it loads before device drivers that provide
access to upper memory. Normally, if your hard drive has been compressed
using DriveSpace, DRVSPACE.BIN is loaded even if you press F5 or F8. For
information about starting your computer without loading DRVSPACE.BIN, see
<CONFIG.SYS commands>.

The DRVSPACE.SYS device driver does not provide access to compressed drives;
it simply determines the final location of DRVSPACE.BIN in memory. When
loaded with a DEVICE command, the DRVSPACE.SYS device driver moves
DRVSPACE.BIN from the top to the bottom of conventional memory. When loaded
with a DEVICEHIGH command, DRVSPACE.SYS moves DRVSPACE.BIN from conventional
to upper memory, if available. Whenever possible, DRVSPACE.SYS moves a
portion of DRVSPACE.BIN into the HMA.

For more information, see the topic <DRVSPACE.SYS>.

How DriveSpace assigns drive letters

When you install DriveSpace, it creates a new drive and assigns a drive
letter to that drive. DriveSpace skips the first four available drive
letters and assigns the next available drive letter to the new drive. For
example, if your computer has only drives A, B, and C, DriveSpace skips
letters D, E, F, and G, and assigns drive letter H to the new drive.

When assigning letters to additional drives (for example, if you compress
another drive), DriveSpace works backwards from the first drive letter it
assigned. In the example above, DriveSpace would next assign the letter G.

DriveSpace attempts to avoid drive-letter conflicts with drives created by
FDISK, RAMDrive, networks, or other installable device drivers that assign
drive letters. However, if a drive-letter conflict does occur, DriveSpace
resolves the conflict by reassigning its drive letters.

Compressing a RAMDrive

To compress a RAMDrive, use the <DRVSPACE /CREATE> command. Although it is
possible to compress a RAMDrive by using the DRVSPACE /COMPRESS command, it
is not recommended. Due to the inherent volatility of a RAMDrive,
DriveSpace's automatic recovery mechanisms cannot work on a RAMDrive.

If you compress your RAMDrive, make sure the DEVICE command for RAMDRIVE.SYS
appears in your CONFIG.SYS file before the DEVICE=DRVSPACE.SYS command.
Otherwise, the compressed RAMDrive will not be automatically mounted when
your computer starts.


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Last update: December 07, 2002 14:45 by
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