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Re: [art] Predictable Internet Time

Nico Williams <nico@cryptonector.com> Wed, 29 March 2017 02:58 UTC

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Date: Tue, 28 Mar 2017 21:58:13 -0500
From: Nico Williams <nico@cryptonector.com>
To: Joe Touch <touch@isi.edu>
Cc: art@ietf.org
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References: <alpine.DEB.2.11.1701031348430.7102@grey.csi.cam.ac.uk> <f94415b6-d9f7-0a03-cf5b-ce39c109aa71@isi.edu> <f9429571-b9d5-75d4-9b46-b877a189a7bf@gmail.com> <20170328173916.GE7490@localhost> <e73d5c15-1ba3-8162-f7df-555e2e8588a6@isi.edu> <20170328224041.GJ7490@localhost> <9ddcde60-a915-a03d-dfc3-2c2c451c398c@isi.edu> <20170329000601.GK7490@localhost> <96ad09b7-7dc2-20e8-2aa4-793310d184f6@isi.edu> <20170329015811.GL7490@localhost>
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Subject: Re: [art] Predictable Internet Time
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On Tue, Mar 28, 2017 at 08:58:12PM -0500, Nico Williams wrote:
> On Tue, Mar 28, 2017 at 05:15:58PM -0700, Joe Touch wrote:
> > >> time_t does not access a SI reference or frankly any other stable reference.
> > > The Open Group man pages I'm looking at don't reference SI, but so
> > > bloody what.  If it says "seconds", it means "seconds".
> > That's the trouble - seconds in SI are not seconds defined as 86400/day.
> > If the units don't match,  then a conversion needs to be included. If
> > the units aren't known, you can't convert accurately.
> 
> POSIX does NOT define seconds in terms of days!  It does the opposite:

Although I can see how to waterboard the spec to get either answer.  If
it were right about POSIX time being UTC (which it's not in practice),
then you'd be quite right about it defining seconds in terms of days...

Would that make POSIX a smeared time standard?  Sure seems that way!

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