This utility script allows displaying and extracting files from backup archives made via the DOS BACKUP.EXE utility. In a DOS environment, RESTORE.EXE is used for this purpose, but it didn't work for me, so I wrote this instead.
Apparently the file format created by BACKUP.EXE changed between DOS 3.2 and DOS 3.3, then again for DOS 6.0. This utility handles only only archives made starting with DOS 3.3 and before DOS 6.0.
Warning: I have used it only on two archives, so it is likely that faced with more real-world examples, it may expose shortcomings.
In my particular case, I had captured a set of 5.25 inch floppy disks via the Kryoflux floppy interface card, which resulted in a set of virtual disk images, eg disk1.img, disk2.img, etc. The contents of these virtual disk images can be accessed via the WinImage utility; this program understands the FAT file system and can display and extract the DOS files to the host file system.
These virutal disk images can also be mounted as virtual floppy disks in the DOSBOX emulator. From there it is possible to run RESTORE.EXE, but recovery of the full archive requires swapping the virtual floppy disk which is mounted (in my case, about a dozen times) while RESTORE.EXE is running. This hitch is that DOSBOX requires running DOS command-line utilities to mount (imgmount) and unmount (mount -u) to perform the swap.
My solution was to extract all the CONTROL.### and BACKUP.### files from the dozen kryoflux .img files all in one directory. From there, the python utility I wrote, dos5_restore.py, will read all the control files, check everything for consistency, then list or extract the archive.
usage: dos5_restore.py [-h] [-d] [-l] [-c] [-t] [-w WILDCARD] [infile]
positional arguments:
infile name of control file to process, otherwise use all CONTROL.### files
optional arguments:
-h, --help show this help message and exit
-d, --debug print out detailed status as the files are processed
-l, --list only list the files contained in the archive
-c, --clobber allow extracted files to overwrite existing files
-t, --timestamp preserve the timestamp on the extacted files
-w WILDCARD, --wildcard WILDCARD
a file name or pattern of which files to extract
The wildcard patterns are typical DOS file patterns:
- asterisk means zero or more of any characters
- question mark means one of any character
This code is released under the MIT License
Copyright © 2020 Jim Battle
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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