[TUHS] PWB - what is the history?

Noel Chiappa jnc at mercury.lcs.mit.edu
Wed May 16 09:56:36 AEST 2018

    > From: Jon Forrest <nobozo at gmail.com>

    > John Mashey had a lot to do with PWB so maybe he can say a few words
    > about it if he's on here.

It would be great to have some inside info about the relationship among the
Research, USG and PWB systems. Clearly there was comunication, and things got
passed around, but we know so little about what was happening during the
period between V6 and V7 when a lot happened (e.g. the changes to C, just

E.g. check out the PWB1 version of exec():


It's been changed from V6 to copy the arguments into swap space, _not_ buffers
allocated from the system buffer pool (which is how V6 does it). So, who did
this originally - did the PWB people do it, or was it something the research
people did, that PWB picked up?

I used to think it was USG, but there's a 'Unix Program Description' document
prepared by USG, dated January 1976, and it's still clearly using the V6
approach. The PWB1 release was allegedly July, 1977:


(Which is, AFAIK, the _only_ set of sources we have for after V6 and before V6
- other than the MIT system, which seems to be basically PWB1.)

So who did the exec() changes, originally?

And I could list a bunch more like this...


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