The Unix Heritage Society mailing list
 help / color / mirror / Atom feed
From: Peter Jeremy via TUHS <tuhs@minnie.tuhs.org>
To: Dave Horsfall <dave@horsfall.org>
Cc: The Eunuchs Hysterical Society <tuhs@tuhs.org>
Subject: Re: [TUHS] The 2038 bug...
Date: Mon, 4 Jan 2021 19:22:00 +1100	[thread overview]
Message-ID: <X/LQKPMbiMF45KMJ@server.rulingia.com> (raw)
In-Reply-To: <alpine.BSF.2.21.9999.2012311806460.82237@aneurin.horsfall.org>

[-- Attachment #1: Type: text/plain, Size: 1455 bytes --]

On 2020-Dec-31 18:19:39 +1100, Dave Horsfall <dave@horsfall.org> wrote:
>As the new year is about to kick in (down-under anyway), it got me to 
>thinking (always dangerous): how many here will be around for it to pick 
>up the pieces that are no doubt still lying around?

Alternatively, my understanding is that the Unix epoch changed on
several occasions in the early days.   Presumably the knowledge of
how to achieve this hasn't been lost.  (Though actually performing
an epoch rollover may be more difficult today).

I suspect that 2038 may actually wind up being more serious than Y2K
because there are now far more embedded systems than there were then
but it's not clear that the designers of those systems learnt the
lesson from Y2K.  A few weeks ago I tried to count the number of
CPUs in my bedroom, bathroom and study - my best guess is around 2
dozen.  Admittedly, I think relatively few of those will be concerned
about epoch rollover.

Plus 2038 is merely one epoch.  Someone mentioned the Microsoft epoch
rolling over in 2048.  Between those two, the IBM S/360 epoch rolls
over in 2042 - the Z-series appears to have glued another 8 bits onto
the MSB end of the TOD clock but that won't help all those S/360 and
S/370 binaries that are still being run.  And they are just the well-
known ones.  I expect that there are lots of embedded systems running
custom epochs with weird rollover dates.

-- 
Peter Jeremy

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 963 bytes --]

  parent reply	other threads:[~2021-01-04  8:46 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-31  7:19 Dave Horsfall
2020-12-31  7:24 ` Niklas Karlsson
2020-12-31  8:10   ` arnold
2020-12-31 15:30     ` Warner Losh
2020-12-31 16:09       ` Adam Thornton
2020-12-31 16:12         ` Larry McVoy
2021-01-11  7:18           ` alan
2021-01-11 14:01             ` Stuart Remphrey
2020-12-31 18:36         ` Theodore Ts'o
2020-12-31 21:34           ` Warner Losh
2021-01-06 16:32       ` Dario Niedermann
2021-01-06 17:08         ` Henry Bent
2021-01-06 18:05           ` Dario Niedermann
2021-01-06 18:20           ` Michael Kjörling
2021-01-06 21:09         ` Dave Horsfall
2020-12-31 19:18     ` Bakul Shah
2021-01-04  8:22 ` Peter Jeremy via TUHS [this message]
2021-01-04  9:13   ` Angus Robinson
2021-01-04 21:49   ` Dave Horsfall
2021-01-04 21:56     ` Warner Losh
2021-01-05 18:05       ` Dan Cross
2021-01-06  7:21         ` Warner Losh
2021-01-07 22:56     ` Stuart Remphrey
2021-01-08  1:25       ` Nemo Nusquam
2021-01-10  6:56         ` Stuart Remphrey
2021-01-04  8:59 ` Sergio Pedraja
2021-01-07 22:50 ` Stuart Remphrey
2021-01-10  7:16 ` Valdimar Sigurdsson
2021-01-10  7:24   ` Niklas Karlsson
2021-01-10 10:15   ` Stuart Remphrey
2020-12-31 15:05 M Douglas McIlroy
2020-12-31 16:51 ` arnold
2020-12-31 23:31   ` Steffen Nurpmeso
2021-01-09  8:44 Norman Wilson

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=X/LQKPMbiMF45KMJ@server.rulingia.com \
    --to=tuhs@minnie.tuhs.org \
    --cc=dave@horsfall.org \
    --cc=peter@rulingia.com \
    --cc=tuhs@tuhs.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).