TimeZone - getting next timezone transition

scoops has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I've found the following answer on how to get the next time transition for a timezone in perl:

http://stackoverflow.com/questions/3246215/how-should-i-determine-next-daylight-saving-time-dst-transition-for-a-timezone

I'm wondering how DateTime::TimeZone keeps its timezone transition data up to date?

Thanks

Comment on TimeZone - getting next timezone transition

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Re: TimeZone - getting next timezone transition by ikegami (Patriarch) on Jul 26, 2011 at 04:43 UTC
Are you asking how it keeps your system up to date, or are you asking how it manages to keep track of changes to all the time zones worldwide. If you mean the former, it doesn't. It knows on what dates each timezone enters and leaves Daylight Saving Time, but an update of the DateTime-TimeZone distro is required to get the latest definitions. For example, when the definition of US's time zones changed a few years ago, you would have had to update the distro for it to handle then-future dates correctly. Take a peek at its `Changes` file to see what I mean. If you mean the latter, it gets its data from the Olson database. Update: Major rewrite to improve clarity.	[reply] [d/l]
Re: TimeZone - getting next timezone transition by Jim (Curate) on Jul 26, 2011 at 16:50 UTC
Read Re^2: Impact of U.S. Daylight Savings Time changes in 2007 on Perl distribution/code from January 2007 and pay attention to Dave Rolsky's explanation of how he updates DateTime::TimeZone each time a new version of the Olson tz database is released. Also, take a look at the Changes file for DateTime::TimeZone. Dave does a good job of keeping DateTime::TimeZone up-to-date with the Olson tz database. You need to do an equally good job of keeping your Perl installation up-to-date with the DateTime::TimeZone CPAN module. Consider subscribing to the mailing list datetime@perl.org. Jim	[reply]