From: imp at bsdimp.com (Warner Losh)
Subject: [COFF] Manipulating time_t values (was: Unix half-billion years old 1985)
Date: Mon, 4 Nov 2019 20:07:07 -0700 [thread overview]
Message-ID: <CANCZdfq-+7dXDWS819GjKx4BFdhhdcgcWF5CsXNukWVqjDCiaA@mail.gmail.com> (raw)
In-Reply-To: <20191104235025.C0548156E80B@mail.bitblocks.com>
On Mon, Nov 4, 2019, 5:00 PM Bakul Shah <bakul at bitblocks.com> wrote:
> On Tue, 05 Nov 2019 10:00:55 +1100 Greg 'groggy' Lehey <grog at lemis.com>
> wrote:
> >
> > [Moved to COFF]
> >
> > On Monday, 4 November 2019 at 16:59:22 -0500, John P. Linderman wrote:
> > > I wrote a near-trivial "timestamp" command to make it easier to do time
> > > arithmetic
> > >
> > > TZ=udt timestamp
> > > 119 11 04 21 50 06 18204 1572904206 Mon Nov 4 21:50:06 2019
> > > TZ=udt timestamp 0
> > > 70 01 01 00 00 00 0 0 Thu Jan 1 00:00:00 1970
> > > ...
> >
> > FreeBSD has this functionality in date(1):
> >
> > TZ=UTC date -r 500000000
> > Tue 5 Nov 1985 00:53:20 UTC
> > TZ=UTC date -r 1500000000
> > Fri 14 Jul 2017 02:40:00 UTC
>
> Shouldn't that be
> Tue 5 Nov 1985 00:52:57 UTC
> Fri 14 Jul 2017 02:39:23 UTC
> given that this is UTC (which is 37 seconds behind TAI)?
>
The delta was closer to 18 in 1985 and 36 on 2017. But that doesn't matter.
Sorry :-)
>
No. POSIX says leap seconds do not exist for the computation of these
numbers. Greg's numbers are POSIXly correct.
Warner
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next prev parent reply other threads:[~2019-11-05 3:07 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <alpine.BSF.2.21.9999.1911050805570.11612@aneurin.horsfall.org>
[not found] ` <alpine.BSF.2.21.9999.1911050809230.11612@aneurin.horsfall.org>
[not found] ` <CAC0cEp_WX_aXRWnHcat8ZYbdvf8aeudGoU_SA2+Nj0Nc7v9sKA@mail.gmail.com>
2019-11-04 23:00 ` grog
2019-11-04 23:50 ` bakul
2019-11-05 3:07 ` imp [this message]
2019-11-05 11:13 ` dot
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