Questions about tzdata implementations
ceberle at co.pierce.wa.us
Mon Mar 29 18:10:33 UTC 2010
I apologize if this isn't the right place for this question, but would
appreciate any help with tracking down the answer to these questions.
Background: We have Java web services that send back date/time values with GMT
offsets adjusted for DST following historical rules that match what I see in the
northamerica file for America/Los_Angeles. Our client code is largely
about when DST starts or ends (dates before 2007 on Windows and before 1950. As
one can imagine, this has caused a few problems.
writing one myself (if anyone knows of a solution, I'd appreciate any pointers).
1) Is there some reference implementation for the algorithm that selects the
correct rule for a given date?
2) For the general US rules, there is a rule that says DST started in 1945 on
Aug 14 at 23:00; however, my tests in Java indicate that DST was observed from
Feb 9 1942 through Sep 30 1945, continuously. The latter matches the historical
information I've found. Is this rule superfluous?
Again, any tips would be appreciated.
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