[TUHS] Unix v7 icheck dup problem

Noel Chiappa jnc at mercury.lcs.mit.edu
Sat Mar 4 04:22:00 AEST 2023


    > From: KenUnix

    > So is it safe to say there is no fsck or similar for v7?

There was a version of 'fcheck' (are 'fsck' and 'fcheck' the same program?)
for V7, but I don't know if it's available. It would be really easy to
convert the 'fcheck.c' that I put up to a V7 version; the V6 and V7 file
systems are almost identical, except for the block size, I think.


    > From: Dan Cross

    > I believe you posted a link to end(3) here back in 2018

Yes, but that does't talk about '_end' not being defined if there
are missing externals, either! All it says is:

  "Values are given to these symbols by the link editor 'ld' when, and only
  when, they are referred to but not defined in the set of programs loaded."

Now that I think about it, I have this vague memory we had to look at the
source for 'ld.c' to verify what was going on!


    > From: Jonathan Gray

    > That is close, but slightly different to the PWB fcheck.c

Interesting. I wonder how 'fcheck' made it from CMU to Bell? Clem and I
discussed how it made it from CMU to MIT, and we think it was via Wayne
Gramlich, who'd been an undergrad at CMU, and then went to grad school at MIT.

I'm pretty sure the reason we liked it was not any auto-repair capabilities,
but ISTR it was somewhat faster than icheck/dcheck. (Interesting that they were
separate programs in V6; V5 seems to have only had check:

  http://squoze.net/UNIX/v5man/man8/check
  https://minnie.tuhs.org/cgi-bin/utree.pl?file=V5/usr/source/s1/check.c

which contained the functionality of both. I wonder why they were split?
Space?)


    > From: Rich Salz

    > But the amazing point was it worked regardless of bit order.

I forgot to mention thast, but yes, its input was the number in bit-serial
form. I suspect there's a connection between the property he mentioned, and
the fact that the grad student could design something which would work with
binary numbers fed in from either end, but I can't bring myself to devote the
brain cells to figure it out.


    > From: John Cowan

    > I didn't know that one was done at MIT.

Yes; see:

  https://www.hactrn.net/sra/alice/alice.intro

There's a really funny story at the end of that about the real Ann Marie
Finn. In Rob's version, she took the role of KAREN in the earlier one. That
would be Karen Prendergast, Patrick Winston's admin; why we used her I don't
know, since I didn't really know her, but I guess she had a reputation as a bit of
a 'tough cookie'.

    >> I think that the person fails their oral. I have no idea if it's a
    >> true story.

    > That's vicious.

Hey, this _is_ the school that used to tell incoming freshpeople, at the
welcoming picnic 'look at the person to your left, and to your right; at
graduation, one of you won't be here'. I don't remeber if they said the same
thing at mine, or if the story had just been passed down from class to class.

	Noel


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