Time Zone Localizations

Paul Eggert eggert at CS.UCLA.EDU
Mon Jun 14 05:00:59 UTC 2004

"Mark Davis" <mark.davis at jtcsv.com> writes:

> You are saying that if I generated a series of dates, one per year,
> going back 100 years, that the format would change in the middle?

Absolutely, if by "dates" you mean time stamps including the name of
the local time in question.  This is the only feasible way to address
the problem.  Locations can have several different UTC offsets over
the years (not just two).  For example, "Sri Lanka Time" means UTC+6
for current time stamps, but it means UTC+6:30 for time stamps in
summer 1996 because Sri Lanka changed its definition of standard time
in October 1996.

Numeric UTC offsets avoid this problem, but of course they have some
other problems of their own.  There's no free lunch here.

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