Clem doesn't mention CP-67/CMS, which IBM kept trying to kill in favor of
CMS.
From Melinda Varian's amazing history of VM, I gleaned these factoids:
CP-67 - 8 sites by May '68
Feb of 68 - IBM decommits from TSS
Apr 69 - IBM rescinds decommit of TSS
CP-67 - 44 sites by 1970, ~10 internal to IBM
May 71 - TSS finally decommitted

So TSS was a rocky road, while CP&VM were simple and just worked.



On Sat, Dec 17, 2022 at 9:13 AM Clem Cole <clemc@ccc.com> wrote:

> Given the number of ex-MTS (Bill Joy and Ted Kowalski, to name two) and
> TSS hackers that were also later to be UNIX hackers after their original
> introduction to system programming as undergrads.  I will keep this reply
> in TUHS, although it could be argued that it belongs in COFF.
>
> Note good sources for even more of the background of the history politics
> at both IBM & GE can be found in Haigh and Ceruzzi's book: "A New History
> of Modern Computing
> <https://www.amazon.com/New-History-Modern-Computing/dp/0262542900>" -
> which I have previously mentioned as it is a beautiful read.
>
> On Fri, Dec 16, 2022 at 5:27 PM Douglas McIlroy <
> douglas.mcilroy@dartmouth.edu> wrote:
>
>> IBM revealed Gerrit Blaauw's skunk-works project, the 360/67,
>> but by then the die had been cast. Michigan bought one and built a
>> nice time-sharing system that was running well before Multics.
>>
> All true, but a few details are glossed over, and thus, this could be
> misinterpreted - so I'm going to add those as one of the people.
>
> TSS and the /67 was IBM's answer to Multics, as Doug mentions.  Note that the
> /67 could run as a model /65, which as I understand it, most of the ones
> IBM sold did.
>
> At the time, IBM offered the /67 to Universities at a substantial discount
> (I believe even less than the /65).  Thus, several schools bought them with
> Michigan, CMU, Cornell, and Princeton that I am aware of; but I suspect
> there were others.
>
> TSS was late, and the first releases could have been more stable.
>  Cornell and Princeton chose to run their systems as /65 using the original
> IBM OS.  CMU and Michigan both received copies of TSS with their systems.
>  Michigan would do a substantial rewrite, which was different enough that
> became the new system MTS.   CMU did a great deal of bug fixing, which went
> back to IBM, and they chose to run TSS.  [I believe that CMU runs OS/360 by
> data and TSS at night until they felt they could trust it to not crash].
> Nominally, TSS and MTS should share programs, and with some work, both
> could import source programs from OS/360 [My first paid programming job was
> helping to rewrite York/APL from OS/360 to run on TSS].  So the compilers
> and many tools for all three were common.
>
> MTS and TSS used the same file system structure, or it was close enough
> that tools were shared.  I don't know if OS/360 could read TSS disk packs -
> I would have suspected, although the common media of the day was 1/2" mag
> tape.
>
> This leads to a UNIX legacy that ...  Ted's fsck(8) - which purists know
> as a different name in the first version -  was modeled after the disk
> scavenger program from TSS and MTS.   icheck/ncheck et al. seem pretty
> primitive if you had used to see the other as a system programmer first.
>  Also, a big reason why all the errors were originally in uppercase was the
> IBM program had done it.  In many ways, neither Ted nor I knew any better
> at the time.
>
> Clem
>
>
>
>