C O N T E N T S :
A N I N T R O D U C T I O N T O C O H E R E N T
What is Coherent?
Will Coherent run on my system?
What incompatibilities are known?
Does Coherent support SCSI drives:
Can I still run DOS?
What about technical support?
What revision is Coherent?
How many people run Coherent?
Can postings be made in this news group (comp.os.coherent)?
Public domain software:
Where do I get the public domain software?
Heated discussions of the group:
T E C H N I C A L T I P S
Usenet news software:
The 64K question:
How to create a bootable >>>R/W<<< floppy from Coherent
C O N T R I B U T O R S :
Peter Fillingham [email protected]
Joachim Riedel [email protected]
Mike Willett [email protected],
and The Mark Williams Company
Please read the disclaimer near the end of this
article before attempting anything in reference
to this article.
A N I N T R O D U C T I O N T O C O H E R E N T
WHAT IS COHERENT?
Coherent is a multi-tasking, multi-user operating system for IBM PC's
and compatibles. It will run on most systems with a 286, 386, or 486
CPU. Coherent closely represents the Unix operating system, but, it is
not Unix. Coherent appears to be very similar to System 7 Unix, or for
those of you that have not had the pleasure, close to System 5 Unix.
Coherent includes uucp (Coherent to Coherent Copy) 🙂 and many more
functions you would expect with Unix. Coherent is small and simple,
easy to maintain, and does not require extensive CPU resources to
operate well. It does not have network nor X windows support, and does
not require an AT&T license for Unix. It is as advertised, a quick,
elegant Unix-like multi-tasking, multi-user Operating System, with good
WILL COHERENT RUN ON MY SYSTEM?
Coherent runs on just about all 286-386-486 systems. To list them here
would make this document far too lengthy. It is suggested that if you
are in doubt, buy Coherent, and when it is almost beyond a doubt that
you can not run Coherent on your machine, to return the software and
documentation to the the Mark Williams Company within 60 days for a
full refund as per their policy.
WHAT INCOMPATIBILITIES ARE KNOWN?
IBM XT compatibles will not work, since the Coherent operating system
uses the 286 protected mode. Coherent will not run on an AT&T 6300,
IBM PS/2 model, or with the Western Digital WD1004-27X (XT) or other XT
controllers. Coherent exhibits a slight problem with 386 AMI BIOS,
whereas Coherent requires a cold boot (hit the reset switch, not CTL-
ALT-DEL) to boot Coherent after previously running DOS. Also, Coherent
support engineer ([email protected]c.com) issued a statement to direct people
away from IDE drives if at all possible, because IDE drives are hard to
support, and are not standardized. Coherent does run on many IDE
DOES COHERENT SUPPORT SCSI DRIVES:
Coherent3.2 release now supports the following SCSI drive controllers:
Adaptec AHA-1540 a/b controllers,
Seagate ST01 and 02 controllers,
Future Domain controller, and
Smart Connex SCSI controller
CAN I STILL RUN DOS?
Yes, Coherent can reside on a disk partition separate from DOS, and
likewise DOS on a partition separate from Coherent. You can boot
either one at boot time via a "boot strap" program. They will not run
concurrently however. DOS file systems are available to Coherent with
the Coherent DOS command, so files can be transferred from DOS to
Coherent, Coherent to DOS.
WHAT ABOUT TECHNICAL SUPPORT?
It is generally felt that Mark Williams Company provides excellent
technical support of their software within the U.S.A.. They can be
reached via phone (708) 291-6700, or email:
uunet!mwc!support (General uucp address)
[email protected] (Internet address)
mwcbbs!support (from your system directly to the uucp connection
they provided by the Mark Williams Company)
WHAT REVISION IS COHERENT?
Coherent is presently at the 3.2 revision. Both first-time install
packages as well as updates are available. [email protected] has stated
that the updates are available to registered users at this time.
Features of the 3.2 update include:
KSH - A clone of the UNIX System - V.2 Korn Shell
Enhanced version of the Bourne Shell
New mail facility, supporting domain-style routing
Enhanced troff, that supports PostScript and LaserJet binary fonts
More than a dozen new commands
New and updated online manual pages
Various minor enhancements and bug fixes
HOW MANY PEOPLE RUN COHERENT?
The Mark Williams Company has stated that the sales volume has passed
25,000 copies since its introduction to the market in 1990.
CAN POSTINGS BE MADE IN THIS NEWS GROUP (COMP.OS.COHERENT)?
It is somewhat accepted that source for Coherent will be posted in this
news group occasionally. Keep in mind that large postings cost money
to those that pay for telephone and connect time, so perhaps a short
posting to query general interest should precede the posting. Direct
mailing should be used if there is small interest, and a posting to
archive sites such as piggy and orca. If the interest is overwhelming,
a posting to this news group may be in order, along with posting to an
archive site such as piggy and orca. Posting to this newsgroup has been
a topic of constant debate... 🙁 We hope to soon have a source news
group for coherent, yet another topic of debate... 🙂
PUBLIC DOMAIN SOFTWARE:
Several public domain packages are available for use on a Coherent
machine. These range from improved mailing packages and spread sheets,
to at least four news programs, such as bsnews, cnews, gnews, wnews,
along with readers such as rn, tass, and more.
WHERE DO I GET THE PUBLIC DOMAIN SOFTWARE?
There are several ways to get public domain software:
1. Mark Williams Company bbs (mwcbbs)
2. FTP sites (piggy and orca)
3. Mailserver ([email protected])
4. Privately owned BBSs
Access information on the mwcbbs is included in the documentation
provided with Coherent. In short, it is a uucp site with public domain
software as well as updates to the Coherent release, along with
Coherent news (not usenet) and a "home" for all Coherent sites to uucp
to. For most of us, that is a long distance phone call, as the Mark
Williams Company is located in Illinois.
On the Internet, a number of sites have provided access to public
domain software via ftp. So far these are:
Machine I'net Address Archive administrator
--------------- ------------- --------------------
piggy.ucsb.edu 126.96.36.199 [email protected]
orca.alaska.edu 188.8.131.52 [email protected]
"Piggy" has been the most popular site for Coherent ftp and is often
referred to in comp.os.coherent discussions. Please show your
appreciation for utilizing the archives by limiting access to "off
hours". An occasional thank you note is probably appreciated too, as
archiving and ftp administration is often a thankless job, and a very
generous privilege offered to you! ftp can be used with the login name
"anonymous" and enter your email address as a password, such as
[email protected] has been offering a mailserver service before the
start of comp.os.coherent. It is a gateway between two nets:
Machine Address Mailserver Administrator
[email protected] (CREN) [email protected]
[email protected] (Internet)
[email protected] is bidirectional gateway between the ListServ list
Coherent and Usenet group comp.os.coherent, Co-owned and Administered
by John Harlan and Phil Corporon. All original postings to
comp.os.coherent Usenet group are automatically distributed to the
ListServ list, and everything posted to the ListServ list Coherent, is
automatically posted to comp.os.coherent on Usenet. John Harlan
humorously adds: "And all without mail looping :-)"
To get a list of Coherent files from ListServ, mail the ListServ
mailserver as follows, with the contents of the message being the
% mail [email protected]
Subject: Hello ListServ
Privately Owned BBSs:
Administrator: Joachim Riedel
Email Address: [email protected], uunet!unido!connie!jr
Available Times: 8 AM - 6 PM and 9 PM - 6 AM
Phone number: +49 69 85 87 11
1. closed last week in September and first week in October.
2. expect to call twice so permissions can be set up.
3 1200/2400 Baud MODEMS: ATS9=20 may help with problems connecting.
HEATED DISCUSSIONS OF THE GROUP:
Mark Williams Company has a patent on bit ordering, which is a software
patent. Most think that this is obvious art in software, and should
not be patentable, not to mention a move in the software world (i.e.,
FSF) that "software" should not be patentable in the first place. The
Mark Williams Company has committed to comment on this some time in the
T E C H N I C A L T I P S :
Q: What devices should I use with a modem for dialing in / dialing out
A: For dialing in you should use a device with modem control. For example
com1r or com2r. That is important to ensure that when the calling site
dropped carrier, that also at your site SIGHUP is sent to already running
processes, to ensure that the modem hangs up (dropping DTR) and a new
getty is opened on that port to enable further logins.
For dialing out or local terminals you do not need modem control
Also you do not have to worry about cabling problems, just use some
of those null modem cables available in most computer stores.
Q: How do I enable logins via modem to my machine:
A: I assume that modem is set to AUTO-ANSWER (ATS0=1) and the cabling
Edit the file /etc/ttys. Here an example for com2:
0 = not yet enabled (enable = allow login, run getty)
r = remote access (will enable asking of a password
for remote-access (see /etc/passwd)
Why ? System security, additional password
P = speed (your modem is connected to the computer)
P = 9600 Baud, I use this for my Telebit Modem
com2r = device with modem control, when CARRIER is lost it
will sent SIGHUP to all processes running on that
line and will also drop DTR so a modem hangup or
a modern modem does a hardware reset.
Now type the following:
enable com2r (for Coherent 3.2 that's enough)
kill -1 1 (Coherent 3.0.0 or 3.1.0, Process INIT will start
a getty on com2r)
Q: Can I use fast modems with Coherent ?
A: Yes you can. But you must think about the following:
a) maximum Baudrate between modem - machine is 9600 Baud
(Coherent as a multiuser/multitasking environment is
not fast enough for 19200 Baud)
b) cps-rates in transfer depend on modem/method
calling into my machine (T2500) with a USR, using sz for transfer:
480 cps to 600 cps (compressed, uncompressed files)
calling out with uucp (T2500):
The rate may differ if you use a slow 286 or 386. The above results
were yielded with a 386/33.
Q: I want to use Coherent as a multiuser operating system. How many
users can work with it at the same time ?
A: Now 11 User:
console : 1
com1 : 1
com2 : 1
Multiport : 8
I still do not know if there are device drivers for intelligent
Multiport-Cards but as far as I know there are only drivers for
"dumb" Multiport-Cards and only in polled mode.
Therefore you need a very fast machine for "multiuser"
USENET NEWS SOFTWARE:
Q: Is there any Net-News Sofware for Coherent ?
A: Yes, there are several packages available:
1. CNEWS - the famous package
difficult to install (although there is a nice installation
script in the Coherent version). Only for advanced users !
Has no reader !
2. WNEWS 3.0 - News for MINIX, ported to Coherent
based on BNEWS - small, not bad
Has no reader
3. GNEWS 2.0 (or newer now ?)
all you need for News, easy to install, Newsreader, nice
the well known newsreader
curses based newsreader. Nice, but you should not have
too much groups or articles in /usr/spool/news.
small news package for receiving news via email
Q: I do not like Coherent's mailer. What can I use instead of it ?
A: WMAIL 3.63 - a minix port, MAILX-clone
comb 1.29 - curses based mailer, nice interface
You should ensure that in both cases you have smail 2.5 as
a smart-mailer that understands domain addresses.
smail 2.5 is already in Coherent 3.2
THE 64K QUESTION:
Q: Does Coherent really have a 64 kb limitation ? I want to port
the GNU-C-Compiler and compile big programs.
A: Coherent programs are limited to 64 K for code and 64 k for data
and stack. The limit is not in the compiler, it's in the kernel
or at least in the actual system design. No process can exceed this
But Binaries in Coherent are about 40 % smaller so big programs
for "Real-UNIXES" may also be portable
Q: I write a C-program that seems to be ok but it still core dumped.
Is this a compiler error ? Is my program wrong ?
A: If a program needs a lot of space for local data (resided on the
stack in most cases) then the maximum size for the stack may be
exceeded and your return addresses or other important things were
With the program fixstack you can increase the size for the stack
(and also cut the space for data)
Try size my_prog before and after fixstacking to see the difference.
Q: What hardware (Motherboard, hard disk) do I need for Coherent ?
A: Difficult question. Minimum is a AT 286 with 640 KB RAM and a
hard disk (MFM,RLL,ESDI,SCSI (some), IDE (some)) with at least
10 MB free disk space.
Nevertheless Coherent is not the fastest operating system, so
a 386 with at least 25 MHZ and 4 MB RAM and a fast hard disk
(a hard disk is always too small !!!!) is the minimum config-
uration for a usable multi-user-operating.
Q: I compiled a program that uses termio but it did not work.
A: The termio in Coherent (at least 3.1.0 and the first 3.2.0) did
not work in all cases. So try the sgtty, that works fine.
When porting programs try to find the -DBSD-parts. There you will
find in most cases the sgtty-parts you need for porting.
Q: I compiled a program that uses curses but the screen sometimes get
garbled or the machine seems to hang
A: Maybe you still have an old libcurses.a. Replace it with a newer
Q: I often loose email or files after receiving them with UUCP.
A: Try to get the newest UUCP-update from MWCBBS. The old packages
still have some problems. Check the permissions, at least for example
with comparing them with those on your original diskettes.
Check also the permissions of the needed directories.
In /usr/spool/uucp/Logs./uucp-program you will find the "hints" of the
"uucp-program" (uucico, uucp, uux,uuxqt) what goes wrong.
In Coherent 3.2. you have the program uucheck that will check your
uucp-installation and is also able to "fix" problems. But you have to
run it twice if you run it as root because the first time it creates
the needed directories and the second run sets the correct permission.
HOW TO CREATE A BOOTABLE >>>R/W<<< FLOPPY from Coherent
The COHERENT Operating System Release Notes (Release 3.1.0)
along with the main manual suggest ways of creating a bootable floppy.
One difficulty of this procedure is that, after producing a bootable
floppy, one can't write to it ! The following shell programs are
suggested as a way making a bootable floppy, and below is the fix
recommended by mwc for making the bootable floppy system read-write.
(0) first boot your system from your hard disk, login in as root, use
mkdir to make a convenient subdirectory [e.g., /bin/temp ]. cd to
/bin/temp. Place disk #1 of your mwc original floppies in drive A:,
dd if=/dev/fha0 of=cohboot count=80 bs=30b
Run it in the background if you wish [follow the above line with an &;
use ps -axfl is you are curious]. This will take just over three
minutes depending on the speed of your system. What is going on is
that dd is creating an image of your boot floppy in you default
directory with the file name cohboot.
(1) Next run the following shell program:
echo "/etc/fdformat -v /dev/fha0"
/etc/fdformat -v /dev/fha0
echo "/etc/bad scan -o proto /dev/fha0 2400"
/etc/bad scan -o proto /dev/fha0 2400
Run it in the background if you wish; it takes time. The echo lines
simply display each command line just before it is carried out to tell
you what is going on. The second and fourth lines format the floppy and
check for bad blocks, respectively. In addition, a file (proto) is
being built in your default subdirectory. This file will contain a
list of the bad blocks: look for a line with %b in it. Probably it is
best to use only a floppy with NO bad blocks: so try until you find
(2) make sure you have a subdirectory /f0 on your hard disk;
if not, use mkdir /f0.
(3) Next run the following shell program:
echo "/etc/mkfs /dev/fha0 proto"
/etc/mkfs /dev/fha0 proto
echo "cp /conf/boot.fha /dev/fha0"
cp /conf/boot.fha /dev/fha0
echo "dd if=cohboot of=/dev/fha0 count=80 bs=30b"
dd if=cohboot of=/dev/fha0 count=80 bs=30b
echo "/etc/mount /dev/fha0 /f0"
/etc/mount /dev/fha0 /f0
echo "cd /f0 "
echo " DONE but f0 still mounted !"
The second line produces the file system on the floppy using the
information from file proto. The fourth line copies boot.fha to the
floppy. The sixth line transfers the image of your system boot floppy
to your newly formatted disk (note all these things take time).
Finally, the floppy is mounted so that while you have booted from the
hard disk and have root permissions you can write to the floppy. The
last line simply rings the bell and tells you it is done.
(4) next (noting that your default directory is /f0, i.e. the
floppy disk) enter:
mv begin autoboot
the response is
then a response appears
and you should get back your prompt.
(5) Finally while the floppy is still mounted, cp over your most useful
programs to the appropriate directories (e.g., vi or me, du, df
...) Lastly umount f0, shutdown, sync and boot your writable
ANY REFERENCE TO THIS ARTICLE, IN ANY FORM, IS PURELY AT YOUR OWN RISK!
All opinions, tips, and instructions in this article are those of
the contributors, and not of any company associated with the
individual contributor, or any company mentioned in this article.
Any reference to this article is done purely AT YOUR OWN RISK! The
information contained within is not guaranteed to be free of errors
in any way.
The intention of this note is only to inform curious usenet readers
about some aspects of the operating system of Coherent, and those
companies mentioned are encouraged to add corrections, additions,
or suggest deletions to this note to as per their policy or
willingness to provide positive criticism.
Unix is the trademark of AT&T / Unix System Laboratories, Inc.
Coherent is the trademark of the Mark Williams Company.
Michael Willett, [email protected] uupsi!monarch!mike uunet!csn!monarch!mike
So much fun, so little time to enjoy it...