On Fri, Aug 24, 2018 at 10:02 AM Dan Cross <crossd@gmail.com> wrote:
It's my subjective impression, based largely on what I read here on TUHS, that there was quite a lot of activity and cross-pollination in and out of Bell Labs at the time, so I'm not surprised that the details here are fuzzy.
Amen - 
The Ritchie compiler
in particular, as well as
the Research Kernel
and BSD
releases
are examples a continuous development and express
specific
points in time.
The people and thus knowledge were fluid (a.k.a. 'open source ;-) and features within the system followed the people.

The reasons, order and local politics for many things are sometimes forgotten.   Different actions feed back and forth and things get cloudy in the history.   For instance, while people give BSD credit for the Unix networking because it was widely released with BSD 4.2 and 4.3 as the vehicle, it was actually BBN did the original IP and TCP stack that Eric Cooper added to 4.1 and Joy would eventually create sockets in 4.1A.   All of MIT with ChaosNet, UofI and Rand's work on the ArpaNet NCP predates that work and was used by BBN -- as did the 3Com UNET code for V7, much less things like Rashid's Accent work, Mike Malcom and Cheridon's Thoth and later V Kernel. 

This
 is why I try to use other information that we can precisely date, as well as constants like trying code on old V7 releases like Dan just did.  To me 'other information' is like when some of us matriculated at which schools or moved jobs,  i.e. when Ted show up at CMU for his original OYOC year,  Noel's time in Tech Sq, me at CMU or UCB, 
the summer the V6 patch tape
'accidentally' found its way to the Arpanet
 
community can be dated by 
Ken's trip to California/visit to see Chesson who was finishing up at UofI
;
 or big outside actions like the need to support 
to big unmovable
(and thus otherwise datable) items such as
the APS5 or addition of the Vax VM support at UCB
, dvk and my going on strike to force CMU to get a commercial Unix license summer of '78, when UCB got its own C70 IMP instead of the VDHI to LBL for Ing70; etc
.
  Dates of different USENIX conferences, which were were a lot of ideas (and code) moved back and forth.

Clem