Re: [LEAPSECS] Mechanism to provide tai-utc.dat locally

From: Zefram <zefram_at_FYSH.ORG>
Date: Wed, 27 Dec 2006 13:32:25 +0000

Tony Finch wrote:
>I was thinking partly from the point of view of infrastructure: if you
>have a mechanism that can keep the system's timezone database up-to-date,
>then it is adequate for keeping the leap second table up-to-date.

The Olsen software has a built-in assumption that the timezone database
never changes. After loading timezone data from disk it never checks to
see if it's changed, so it'll miss any change that was announced after
the program started running. I don't think that's adequate for leap
second data. I'm pretty unhappy about it for timezone data too.

The Perl DateTime::TimeZone code, based on the Olsen database,
similarly doesn't handle updates: the data is compiled to Perl code.
DateTime::LeapSecond compiles the leap second table as Perl code,
suffering the same problem.

Your principle is probably correct; I'm just saying that the
implementation you're thinking of doesn't actually satisfy the criterion.

-zefram
Received on Wed Dec 27 2006 - 05:32:52 PST