For definitions of terms used in this article, please see the
MS-DOS uses the DBLSPACE.BIN component to mount the compressed volume
file so you can access the files on your compressed drive. This file
loads automatically if it is in the root directory of the startup disk
(no device= line is needed). If you want to load DBLSPACE.BIN into
upper memory, see the DBLSPACE.SYS section of this article.
This file allows you to mount, create or modify DoubleSpace drives.
DoubleSpace accepts the following parameters:
DBLSPACE /CHKDSK [/F] [drive:]
DBLSPACE /COMPRESS drive: [/F] [/NEWDRIVE=drive2:] [/RESERVE=size]
DBLSPACE /CREATE drive: [/NEWDRIVE=drive2:] [/SIZE=size | /RESERVE=size]
DBLSPACE /DEFRAGMENT [/F] [drive:]
DBLSPACE /DELETE drive:
DBLSPACE /FORMAT drive:
DBLSPACE [/INFO] drive:
DBLSPACE /MOUNT[=sss] [drive:] [/NEWDRIVE=drive2:]
DBLSPACE /RATIO[=r.r] [drive: | /ALL]
DBLSPACE /SIZE[=size | /RESERVE=size] [drive:]
DBLSPACE /UNMOUNT [drive:]
For more information about DoubleSpace command-line options, type HELP
or HELP DBLSPACE /switchname
(where /switchname is the name
of the switch about which you want more information) at the command
This file contains help on DoubleSpace. To access this file, run
DoubleSpace and choose Contents or Index from the Help menu.
The DoubleSpace Setup information file is helpful when creating a new
DoubleSpace drive, but it is not required.
Commands under the [SpecialFiles] section indicate actions to be taken
for specific files; the possible actions are COPY=, IGNORE= and MOVE=.
Without a path, any file of that name will match; wild cards (?, *)
Programs under the [CopyFiles] section are optional utilities that
are left on the original boot drive if there is enough room.
Programs under the [dangerous] section will be remarked out using the
REM command from CONFIG.SYS file during DoubleSpace Setup but will not
be remarked after Setup has completed.
Programs under the [prior] section will have DEVICEHIGH=DBLSPACE.SYS
placed ABOVE them in the CONFIG.SYS file.
This file is used by DoubleSpace to mount the compressed volume and
swap drive letters. The file contains the following settings:
This is a temporary file that DBLSPACE.BIN generates to keep track of
windows information when a drive is compressed. It should
automatically be deleted after DBLSPACE.BIN completes the compression
of the existing drive.
The DBLSPACE.SYS device driver does not provide access to the
compressed drives, but it does provide the following functionality:
• Allows DBLSPACE.BIN to be loaded high (using the devicehigh
• Moves DBLSPACE.BIN from the top of conventional memory to the
bottom (as device drivers load). This can eliminate conflicts
with programs that require access to the top of conventional
A compressed drive is not a real disk drive, although it appears that
way to most programs. Instead, a compressed drive exists on your disk
as a hidden file called a compressed volume file (CVF). DBLSPACE.00x
is the compressed volume file.