[tz] How to compute the moment of the next DST change

Simon Perreault simon.perreault at viagenie.ca
Wed Apr 3 05:55:48 UTC 2013

Le 2013-04-03 04:45, Paul Eggert a écrit :
>> Looking at the source code of "calendar-next-time-zone-transition",
>> it looks very error prone to me. Am I reading the comments right?
>> It initializes a binary search with the results of a heuristic?
> Yes.  It's a heuristic that should work with all real-world time zone
> histories (including all time zone histories in the tz database).
> It won't work in general, though.

Thanks! That's what I expected.

> zdump uses a similar heuristic, if memory serves.

I suppose magic doesn't exist after all...

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