[time-nuts] The Problem with Time & Timezones - Computerphile
cheater00 at gmail.com
Sat May 10 07:28:10 UTC 2014
On 9 May 2014 21:01, "Hal Murray" <hmurray at megapathdsl.net> wrote:
> holrum at hotmail.com said:
> > Ahh, but with Lady Heather you can specify the time zone offset (down
> > the second) and the when the daylight savings time switchovers occur.
> > from experience, I can tell you that the code to do it is a royal pain
> > the ass... not all that hard to do, but a pain to test.
> Part of the problem is that "when the daylight savings time switchovers
> occur" changes over time. The problem is a whole lot easier if all you
> interested in is converting the current UTC to the current local time.
> The *nix world uses the time-zone database. I assume it is available on
> Windows too.
That is the Olson Timezone Database, aka tzdata. I wrote a compiler for it
once, the format is very fun to parse and there are some great things to be
learned. Specifically figuring all edge cases was a fun exercise.
More information about the Time-nuts_lists.febo.com