Contents of the HDSTRP.DOC file
HEADERSTRIP v.1.0 Copyright (C) 1985 Conrad S. Kageyama, 25 October 1985
Not for commercial use or commercial gain. Intended solely for use in the
When a hard drive is backed up using DOS's BACKUP.COM, the resulting files on
the backup diskettes are unusable because DOS attaches a 128 byte header to
the front of each file, which tells BACKUP/RESTORE where the file belongs on
the hard disk. It was recently pointed out that even if you are backed up
religiously, if your hard disk fails, then you are still down for the
duration since those files are useless as is.
The result of this comment is HEADERSTRIP (HDRSTRIP.COM), which will strip
out that 128 byte header and write the file back to disk in usable form.
Version 1.0 is a quick and dirty Turbo Pascal program with no bells and
whistles, but it does work and will save the day if you need the files. The
source code is very small, but because of the overhead of a compiled library,
the file is still some 11K big. An assembly language program would be much
smaller and much more economical in terms of storage. If no assembly
language programmer picks up the ball and writes a tighter program, then time
permitting, and if there is demand, I will enhance HEADERSTRIP to make the
operation more automatic. In the meanwhile, though, as stated above,
HEADERSTRIP does work as is, though as with all public domain software, there
are no guarantees, implied or otherwise. Work **ONLY** with copies of your
backup files. Use HEADERSTRIP at your own risk.
1. COPY the needed file from your backup diskette to another diskette.
**DO NOT** work with your original backup diskette.
2. REName the COPY'ed file to some other name; any name will do, i.e.,
3. Invoke HEADERSTRIP by doing HDRSTRIP at the DOS prompt.
4. HEADERSTRIP will now ask you for the Input filename. Respond with
whatever filename you chose, including a drive designator, i.e.,
"b:filename.bak", and hit .
5. HEADERSTRIP will now query you for the Output filename. Respond with
the true filename, including a drive designator, i.e.,
"b:filename.com", or whatever, and hit .
6. HEADERSTRIP will now process the input file, strip out the 128 byte
DOS backup header, and write the file back to disk. The resultant
output file is now usable.
7. The resultant output file may differ in filesize from the original
file on the hard drive depending on how the end of file is handled in
the original, and due to padding at the end of the file, but the
output file should be functionally okay.
Conrad S. Kageyama
Sysop, CIS IBM PC SIG