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From: alan@alanlee.org
To: The Eunuchs Hysterical Society <tuhs@tuhs.org>
Subject: Re: [TUHS] The 2038 bug...
Date: Mon, 11 Jan 2021 02:18:40 -0500	[thread overview]
Message-ID: <32aeb853e5c56bc04dd2e9e2310f96a7@alanlee.org> (raw)
In-Reply-To: <20201231161228.GG28420@mcvoy.com>


64-bit migration is the ideal solution.  However there is a band-aid 
that can be applied to extend the life of 32-bit only systems.  One 
could reclaim part of the previous epoch window going forward.  That is, 
once 32-bit time_t rolls over, assume any value from -2 billion to some 
additional arbitrary positive time offset had indeed just rolled over.  
Add a whole 0x100000000 to it in a 64-bit context and evaluate (or 
evaluate against the old epoch ~+136 years).  It means a 32-bit time_t 
in this context would instead mis-represent dates from 1902 forward to 
some arbitrary threshold as modern >2038 dates.  But time_t was never 
meant to track dates outside of 'near term' relative to 'modern day' - 
eg +/- 68 years from 1970 when it was conceived.  It's reasonable to 
assume as the use of such software has moved forward in time, its time 
reference should as well.

-Alan H.

On 2020-12-31 11:12, Larry McVoy wrote:
> On Thu, Dec 31, 2020 at 09:09:33AM -0700, Adam Thornton wrote:
>> Whereas, time_t is basically internal, right?
> 
> time_t is used in syscalls, see Warner's email about i386.  It's a
> mess for 32 bit kernels.

  reply	other threads:[~2021-01-11  7:28 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 [this message]
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
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

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