Originally posted by: leo@uf-csv.UUCP (Leo Wilson [staff])
Date: Fri, 2-Nov-84 17:09:52 EST
Posted: Fri Nov 2 17:09:52 1984
Date-Received: Mon, 5-Nov-84 21:02:33 EST
Organization: Univ of Fla, Computer and Information Science
This line is intentionally less than witty.
I am posting this summary of responses to my inquiry about write protecting
individual files because of the number of requests I got to forward the
information. Jay at unm-la gave the useful information, which bit to flip.
It works like a charm!
I have a friend with a copy of the Norton Utilities and used it just a few
minutes ago to change the appropriate bit. I imagine there's a few hackers
out there who'll actually use the DOS call, but I'm really a hardware type
who prefers a UNIX environment (DOS means Disk Operating System, I think,
but other than that I'm blissful...) to any other I've seen. You go ahead
and hack, I'll just whittle a little for now.
Bit 0 of byte 11 of a disk directory entry marks (when set) a file as read
only. You can find the directory entry and diddle this bit directly, or
you can use DOS function call 0x43 (CHMOD), specifying the drive:path/file
as an ascii string.
Or, if you want to buy a utility to do it for you, try "AKA Alias", available
from The Programmer's Shop (800)421-8006. It includes "xdir" which gives you
a directory listing showing the attributes of the files, and "chmod" which
sets/resets any of the attributes. (Caveat: don't use AKA Alias for its
advertised purpose -- it knows how to hang your system at the most precious
There is a utility to do that. Fortunately,
DOS 1.1 and above allow files to be marked as 'read-only'.
- Lester Waters -
1. To deal with write-protect/unprotect and other related things,
you might like FilePaq, about $30 + S & H and tax, from
PO Box 36152
San Jose, CA 95158
2. The above disk also includes erase/delete utilities and an
improved directory function. If in addition, you patch
out the names `del' and `era(se)' from command.com and create
batch files, you may solve your erasure problems.
Gene E. Bloch (...!nsc!voder!gino)
The new IBM DOS 3.0 includes a program labeled ATTRIBUTE that can set
and reset a file's attribute to read only.
DOS 3.0 is now available for list $ 65.-.
There are similar utilities on RBBS systems that are in public domain
and accessible if you have a modem and downloading capability.
John Gulbenkian Varian Walnut Creek CA
There are several public domain programs floating around to do this, but
I would recommend buying the Norton utilities. They are very useful.
You could also get DOS 3.0.
David DiGiacomo, BRAG Systems Inc., San Mateo CA (415) 342-3963
Disclaimer: The opinions expressed herein are solely those of the author.
Leo Wilson USPS: University of Florida
akgua!uf-csv(!uf-csg)!leo 512 Weil Hall
CSNET: leo@ufl Gainesville, FL 32611
"There are two types of aircraft: Fighters and Targets."