6 Feb
2026
6 Feb
'26
7:51 p.m.
Dave,
Page 439 of that document you linked has a nice chart of "integrated
emulators that run execute under VM/370" - now I do recall one of the
"famous" things about the prior S/360 was it could emulate 1401 and other
IBM systems. Then later on, more systems to emulate would be the
709-series. Ok, so VM/370 is more like what we might today call a
Hypervisor? So the "it looks like whatever you want" comment makes
sense.
I suppose what I'm after is more a visual on the usage of CMS, DOS/VS or
OS/VS1 ( OS's that one would only use on an S/370 ? )
I put a couple reference images here on what I have about CTSS and TOPS-10
(CTSS is from a modern-day emulators, TOPS-10 is from one of their manuals
so its from in 1970). I see how you mean VM/370 isn't quite the same
nature (not "just an OS" but an enterprise thing like for airlines, banks,
financial brokers -- and the virtualization helped in testing/deploying new
systems -- that maybe had newer OS's -- without disrupting operational
systems?)
https://github.com/voidstar78/OS_NOTES
- Steve
On Fri, Feb 6, 2026 at 10:00 AM David Wade <dave.g4ugm(a)gmail.com> wrote:
On 06/02/2026 14:55, Steve Lewis wrote:
Thanks Dave, the 3270 terminal screen makes
sense. Or to make use of
the system and resources, you'd remote to it using a 3270.
So it may have been at a time no one thought to snap a photograph of
any of those 3270s in use (not just a "room full of 3270's" kind of
photo - but of the actual screen, showing whatever it was they were
doing; managing tape/disk resources, files, users, or running APL or
something. That's more what I was looking for, when you "used VM/370
{or remoted into it}, this is what it looked like."
Generally thats not what you did with VM/370. You edited, compiled, and
ran programs....
There had to be some kind of installer? Or maybe I'm viewing it wrong
- they (a business) didn't just buy a S/370 then decide what OS to
install. But rather it was a packaged prepared by IBM, so maybe it
was pre-installed with VM/370 and configured to whatever the
arrangement/contract was?
For VM you usually got a "starter system" on a tape. There was a
different tape for each disk type. The first file on the tape is the
standalone disk dump and restore program, DDR. So you IPL (boot) from
this tape, and use DDR to restore the starter system to DASD (disk).
You usually needed three packs. The first time you IPL the restored
starter system it asks you some basic config questions, and you then
have a working system that you can use to restore the rest of the
VM/370, load and apply service (fixes) , and configure to your exact
hardware set-up.
I expect at 522 pages this manual which covers install and congigureis a
tad bigger than the one for other systems...
https://bitsavers.org/pdf/ibm/370/VM/370/Release_6/GC20-1801-10_VM370_Sysge…
Or a way to say "when someone used a S/370
{or CMS}, this is what the
console content looked like" (printed, or by that time yea probably
more likely a CRT).
It looked like whatever you wanted. The samples in the previous e-mail
are typical...
“The Origin of the VM/370 Time-Sharing System” –
R.J. Creasy gives a
little bit of a description on those components CP, CMS, and RSCS.
But no photo/image yet of a terminal with content to identify "yeah,
see they are using a S/370 there" (maybe its listing disk packs,
tapes, memory resources, etc?) I got something like this for the
earlier CTSS and TOPS-10.
pass me what you have for that so I can see what a VM Equivalent might
be. The definitive thing on a users 3270 is the status bottom right
which on a pukka system which usually reads "VM READ VM/370" but can
also start "RUNNING", "HOLDING" "CP READ".
-Steve
Dave