[TUHS] A Census of /etc and /sys Prior to V4

Noel Chiappa jnc at mercury.lcs.mit.edu
Sat May 20 12:04:57 AEST 2023

    > From: Matt G.

    > there is a "core" file included, I wonder if kernel text is swept up in
    > that.

My _guess_ is perhaps not; the disks were really small (the UNIX people
started with an RF11, which the first DEC machine I used - a RSTS system -
also had; that was _really small - 512KB :-).

Probably it did whatever V1 did. I was not up for going to look, since I
wasn't familiar with the V1 code - but then I decided to break down and look
at it, and also create a minimal index to say what's in each module. (Here:


if anyone is interested. Made easier because the code is very well commented;
it's very easy to read.)

The code to take core dumps is in u1, at 'badsys:'. It dumps the user's
entire possible memory space (i.e. not just up to the 'break'), and then
(separately) the 'user' area. The system is not included. I doubt V2/V3 are

    > ac and mq EAE registers are still in use in s2-bits binaries

Interesting. How did you work that out, BTW? Also, V1 seems to mandate use of
a KE11-A (use is made of it throughout the kernel).

     > but have been replaced by s1-bits.

Interesting; how did you work that out? V3's core (V):


doesn't give the format, just says "The actual format of the information is
complicated because it depends on what hardware is present (EAE,
floating-point option)". Do you have C3's db(I) source? Oh, wait, TUHS has
what claims to be V2's db source:


but it actually seems to be later; it's conditionalized for having the FPP.
So it must be for a machine running the -11/45 - which we seem to have
decided is V3?

The header for TUHS' V2 says: "The files in cmd/ are recreated from the text
fragments found on the file s1-bits.gz." Which agrees with your take:

    > All in all that pegs the s1-bits fragments as being closer in character
    > to V3

That's all for the moment...


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