From mboxrd@z Thu Jan  1 00:00:00 1970
From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Date: Mon, 30 Jan 2017 10:34:26 -0500 (EST)
Subject: [TUHS] Early Internet work (Was: History of select(2))
Message-ID: <20170130153426.D9CFA18C0B4@mercury.lcs.mit.edu>

    > From: Paul Ruizendaal

    >> the headers say they date from 1974-75.

    > Wow, that's great! That means that you have the initial version.

The file write dates are May 1979, so that's the latest it can be. There is
one folder called 'DTI' which contains an email message from someone at DTI to
someone at SRI which is dated "10 Apr 1979" so that seems to indicate that
that's indeed when they are from.

(The message says that the folder contains the source for DTI's IMP-11A
driver, which is different from UIll's, although they both descend from the
same original version.)

    > Possibly it is V5 not V6

Nope, definitely V6 here.

    > All my leads for the 1975 version of this code base came up dry and I
    > feared it lost.

I could have sworn that I'd seen _listings_ of the code in a UIllinois
document about NCP Unix that I had found (and downloaded) on the Internet, but
I can't find them here now. I did look again and found:

  "A Network Unix System for the Arpanet", by Karl C. Kelley, Richard Balocca,
  and Jody Kravitz

but it doesn't contain any sources.

    > it may contain the first version of 'mbufs'

It might - the code is conditionalized for "UCBUFMOD" all over the place.


    > Yes, a 'history' file seems to have been common practice at BBN. The
    > kernel would have had many modifications:
    > - the 'ports' extension from Rand

Yes.

    > - the 'await' extension by Jack Haverty

Yup.

    > - an 1822-driver

Yes (also by Haverty) - although IMP11-A drivers are all over the place, there
are two different ones in the NCP Unix alone.

    > - possibly, an Autodin II network driver

Didn't see one.

    > - possibly, shared memory extensions

Yes, there are two module in 'ken', map_page.c and set_lcba.c (I was unable to
work out what 'LCBA' stood for) which seem to do something with mapping.

    > It might even have some NCP code in it

Yes, there's an 'ncpkernel' directory.

    > There seem to have been two versions of the BBN modified kernel. One was
    > done for systems without separate I/D with stuff heavily trimmed

Yes, there's a 'SMALL' preprocessor flag which conditionally removes some
stuff.

    > The other may have extended the V6 kernel to run in separate I and D
    > spaces

That capability was present in stock V6.

     Noel