[geeks] Oldest OS Still Developed

[Charles Shannon Hendrix]

Wed, 18 Oct 2006 @ 16:35 -0400, Sridhar Ayengar said:

> Charles Shannon Hendrix wrote:
> >>> 	- MVS
> >> Early to mid 1960's 
> > 
> > No, it was not released until 1974.
> 
> Wrong.  Look at MVT or even MFT from which it evolved.

>From www.research.ibm.com, in the Auslander paper there:

	Since the introduction of MVS in 1974, additional loopholes have
	been identified and closed. Also, more elaborate authorization
	capabilities have been provided, as well as detection capabilities,
	to facilitate the identifi- IBM J. RES. DEVELOP. VOL. 25 NO. 5
	SEPTEMBER 1981 Page 8 cation of a perpetrator, and hardware
	assistance, such as encryption devices

There are several other references at IBM which give 1974 as the release
date.

MVS was a major rewrite of a lot of OS/360 and things like MFT, and you
can read about that at the same site too.

> > DOS/VSE (*) is 41 years old this year, so that puts it at 1965.
> > 
> > * I think this is the right name, not DOS/VE, unless both were used.
> 
> *VSE* is, but OS came out some time before.

>From the same website:

	IBM Endicott developed an alternative operating system designed for
	smaller members of the S/360 family. The first VSE was Disk
	Operating System/360 (DOS/360). DOS/360 first shipped in 1965.

That particular paper calls it DOS/360 and comments that it was supposed
to be a temporary OS that IBM would end-of-life in a few years,
replacing it with OS/360.

Other documents call it "DOS/VSE".

> > IBM must hold the record for how long they'll support a system.
> 
> That's only the half of it.  A 1966-vintage MFT program will happily run 
> under the latest z/OS *without recompilation*.

Not only that, but there are places running programs from the 50s and
60s under emulation, and the emulators are old and are running on top of
new IBM mainframes.

> > RT/11 is an old OS now, but I believe some clone PDP-11 systems still
> > use it.
> > 
> > Seems like it qualifies to me.
> 
> It would if it were anywhere near as old as VSE or TOPS-10.

At over 30 years old, it has to be in the top ten still used and
maintained OS.



-- 
shannon "AT" widomaker.com -- ["There is no such thing as security.  Life
is either bold adventure, or it is nothing -- Helen Keller"]