Re: A structured format for dates?

Poul-Henning Kamp <phk@phk.freebsd.dk> Fri, 17 June 2022 05:34 UTC

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To: Austin William Wright <aaa@bzfx.net>
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From: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Subject: Re: A structured format for dates?
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--------
Austin William Wright writes:

> I don't believe 'works 99.999998% of the time" may be 
> good enough.

Well, that's what everything based on POSIX offers today.

Trying to compensate for that deficiency in the HTTP layer is
counter-indicated:  We should take, and trust, the time from the
platform we run on, and handle leap seconds however that platform
does.  If the platform jumps over leap-seconds, we should
follow it, if it smears over them, we should slide along.

> Rather, if support for fractional seconds is important for any reason at 
> all, [...]

Last we talked about it, the CDN people really wanted it for things like
Cache-Control etc.

> Let me propose a different argument for your case: UTC is inherently 
> discontinuous, [...]

and all HTTP relevant practical realizations of UTC have variable
frequency.

But again: Inventing a new time-keeping paradigm for HTTP is a non-starter.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.