The Eighth Edition is *not* descended from the Seventh Edition.
Submitted by: Greg Lehey <grog@lemis.com>
and Dennis Ritchie
Here's a quote from Dennis Ritchie, posted to Warren Toomey:
[January 1999]
----- Forwarded message from dmr -----
I also got mail from Norman Wilson today about the discussion.
This is mainly to confirm and fill out details of Wilson's account.
The Eighth Edition system started with (I believe) BSD 4.1c and
the work was done on VAX 11/750s -- our group did not get
a 780 until a while later.
Most of the operating system superstructure of BSD was retained
(in particular no one (even the indefatigable Norman)
wanted to get much into the paging code. Norman is also
right that the competitor was John Reiser's (and Tom London's)
32V descendant from another group at the Labs. In structure
this system had a lot to offer (in particular the buffer cache and the page
pool were unified, but it was clear that their work was not being
supported by their own management. It was used for a while on
our first 750 and also our first 11/780 ("alice", a name that lives
in netnews fame preceding the reach of Dejanews).
The big change leading to V8 was the scooping-out and replacement of
the character-device and networking part by the streams mechanism. Later,
Peter Weinberger added the file-system switch that enabled
remote file systems and prescient things ideas like /proc). Weinberger,
as Norman said, also did a simple-minded FFS.
The TCP/IP stack wasn't very important to us then and it has a mixed and
murky history. Much of it came from early CSRG work, but it was converted
to a streams approach by Robert Morris and subsequently fiddled over a lot.
Likewise, as Norman said, the applications (/bin and whatnot) were somewhat
of a mixture. Many were the locally-done versions, some were taken
from BSD in some incarnation, some from System V.
Dennis
----- End of forwarded message from dmr -----
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