[190599] in North American Network Operators' Group
Falsehoods programmers believe about time, etc (was Re: Leap Second
daemon@ATHENA.MIT.EDU (Jay R. Ashworth)
Sun Jul 10 13:34:36 2016
X-Original-To: nanog@nanog.org
Date: Sun, 10 Jul 2016 17:34:32 +0000 (UTC)
From: "Jay R. Ashworth" <jra@baylink.com>
To: North American Network Operators' Group <nanog@nanog.org>
In-Reply-To: <20160709042947.GA24818@cmadams.net>
Errors-To: nanog-bounces@nanog.org
----- Original Message -----
> From: "Chris Adams" <cma@cmadams.net>
> Once upon a time, Patrick W. Gilmore <patrick@ianai.net> said:
>> But time _DOES_ flow. The seconds count
>> =0958, 59, 60, 00, 01, =E2=80=A6
>> If you can=E2=80=99t keep up, that=E2=80=99s not UTC=E2=80=99s fault.
[ ... ]
> Leap second handling code is not well-tested and is an ultimate corner
> case. There's been debate about abolishing leap seconds; with all the
> every-day bugs people have to deal with, few people set up a special
> test environment to handle something that may never happen again (until
> you get less than six months warning that it'll happen at least once
> more), and even then, tests tend to focus on what broke before, because
> it is really hard to test EVERYTHING.
If this particular issue is your beat -- or your avocation -- you really sh=
ould
read both these blog postings, and all their comments; they are nearly
comprehensive:
http://infiniteundo.com/post/25326999628/falsehoods-programmers-believe-a=
bout-time
and
http://infiniteundo.com/post/25509354022/more-falsehoods-programmers-beli=
eve-about-time
They are also both funny as hell.
To myself be comprehensive, I should point out a companion piece about name=
s:
https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-believe-about=
-names/
and there are similar lists for phone numbers, geography, civil addresses a=
nd gender,
linked from this thread:
https://news.ycombinator.com/item?id=3D11321236
If you write any code that has to interface with the outside world, these a=
re pieces
I think you should read at least annually.
Cheers,
-- jra
--=20
Jay R. Ashworth Baylink jra@baylink.=
com
Designer The Things I Think RFC 2=
100
Ashworth & Associates http://www.bcp38.info 2000 Land Rover =
DII
St Petersburg FL USA BCP38: Ask For It By Name! +1 727 647 1=
274
