The Unix Heritage Society mailing list
 help / color / mirror / Atom feed
From: helbig@mailbox.org (Wolfgang Helbig)
Subject: [TUHS] Date madness
Date: Wed, 13 Dec 2017 16:39:24 +0100	[thread overview]
Message-ID: <CA92CED6-504C-4139-8366-6F9C14765184@mailbox.org> (raw)
In-Reply-To: <20171212180117.BFB5918C087@mercury.lcs.mit.edu>

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1847 bytes --]

Hi,

years ago I fixed some overflow bugs in v6. The file ctime.README
reads:
This tape (see enb.README) fixes some y2k and integer overflow issues
in V6.

ctime.c: Use Central European Timezone
	ctime():
	Don't blindly assume "19" to be the first two digits of the year. 
	gmtime():
	The division of the current time by 8 hours overflows nowadays.
	Instead divide by
	24 hours, and use a routine which computes the quotient and remainder
	with unsigned double word arithmetic. (ludiv())
	If you want to understand ludiv and know modern program notations
	have a look at ludiv.README.
	
date.c: Interpret the user entered year "00" as "2000", not as "1900”.

The fixes are distributed on v6-tar tapes enblocked for simh (*.enb)

I think, the enb-directory is archived at tuhs. If not, let me know.

Here is the enb.README:

The contents of this directory are .README and .enb files with the
following basenames:

ctime:	Some y2k related changes to V6.
dcheck: Bug fix and enhancement of dcheck. 
dist:	The V6 distribution tape: dist.README explains how to install
	and setup V6 in the Supnik simulator. The file dist.enb is missing
	for copyright and space reasons, you have to prepare it yourself.
	(see enb.README). 
dotdot: Kernel enhancement: If in a root directoy of a mounted filesystem,
	let ".." mean the parent of the mount point, not the root directory.
enb:	Conventions and usage of .enb files. Contains C-source of a program
	which prepares tape files for the Supnik simulator and tells you
	how to get the V6 distribution tape.
ludiv:	Derivation of a double word unsigned division algorithm, which is used
	in ctime. (no corresponding .enb)
man:	The man command, which was missing from the distribution, and some
	changes do make nroff output readable on an xterm.


Have fun,

Wolfgang Helbig
Stauferstr. 22

71334 Waiblingen






  parent reply	other threads:[~2017-12-13 15:39 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-12 18:01 Noel Chiappa
2017-12-12 18:21 ` Warner Losh
2017-12-13 15:07 ` Random832
2017-12-13 17:00   ` Jason Stevens
2017-12-13 17:18     ` Ron Natalie
2017-12-13 18:02       ` Arthur Krewat
2017-12-13 15:39 ` Wolfgang Helbig [this message]
2017-12-14  0:57 ` Dave Horsfall
2017-12-14 14:09   ` William Cheswick
2017-12-17 16:19     ` Ron Natalie
2017-12-17 16:33       ` William Cheswick
2017-12-17 17:54         ` Random832
2017-12-17 22:15           ` Dave Horsfall
2017-12-17 22:54             ` Ian Zimmerman
2017-12-16 18:12 ` Wolfgang Helbig
2017-12-12 18:31 Noel Chiappa
2017-12-13 15:56 Noel Chiappa
2017-12-13 16:08 Noel Chiappa
2017-12-13 16:23 ` arnold
2017-12-13 16:31 Noel Chiappa
2017-12-13 16:50 ` arnold
2017-12-13 17:16 Noel Chiappa
2017-12-13 18:53 ` Tom Ivar Helbekkmo
2017-12-13 20:46 ` arnold
2017-12-15 16:41   ` Paul Winalski
2017-12-15 17:19     ` Dave Horsfall
2017-12-16 15:45     ` Clem Cole
2017-12-16  3:39   ` Dave Horsfall
2017-12-16  3:45     ` Lyndon Nerenberg
2017-12-17  1:43       ` Dave Horsfall
2017-12-14  3:08 ` Dave Horsfall
2017-12-14  3:13   ` Warner Losh
2017-12-13 19:12 Doug McIlroy
2017-12-14  3:07 ` Random832
2017-12-15  3:04   ` Random832
2017-12-13 20:22 Noel Chiappa
2017-12-13 22:16 Norman Wilson
2017-12-14  0:24 ` Chris Torek
2017-12-17 16:20   ` Ron Natalie
2017-12-17 18:53     ` Tom Ivar Helbekkmo
2017-12-17 20:07       ` Ron Natalie
2017-12-16 10:50 Doug McIlroy
2017-12-16 16:11 ` Random832
2017-12-16 17:11   ` Ralph Corderoy

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CA92CED6-504C-4139-8366-6F9C14765184@mailbox.org \
    --to=helbig@mailbox.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).