[LEAPSECS] BBC radio Crowd Science

[Steve Allen]

On Mon 2017-01-30T14:14:10 +0000, Tony Finch hath writ:
> I think what I was trying to get at (as others have already said in this
> thread) is that you can use the TAI-UTC delta to translate from UTC to TAI
> during a leap second, but you need more information to make the inverse
> translation.

As mentioned by Arias in that radio show, there are leaps of one hour
in time that we deal with regularly.  The tz project has tzdata that
unambiguously represent when the jump occurs, and the tzcode has a
convention for how to interpret the ambiguous hour.

(One thing tz cannot do is represent the legal specification of the
changes in Spain a century ago when the time of fall back was given
by the decree as 25:00:00 on the date in question.  tz encodes
those as 01:00:00 on the next date.)

--
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