I couldn't help noticing that Debian just issued an update
to tzone, so that means Linux systems now know about the
leap second.

-Chuck Harris

Tim Shoppa wrote:
I'm not sure there's any computer time package that correctly disambiguates
23:59:59 vs 23:59:60 in UTC timestamps in a general purpose way. Some
software simply rejects 23:59:60 UTC as invalid, some will quietly map it
to 23:59:59 effectively making those two seconds impossible to distinguish.

There are important systems in the world, those that genuinely have to
distinguish between those two seconds, that do all timekeeping in TAI or
GPS timescales instead of UTC. I think the Olsen timezone database/library
does support TAI. I don't know if the Olsen timzone library supports GPS.

V.P., since you mention Perl and leap seconds, I'd like to point out that
there's a very useful Perl library for computing delta times around
leapsecond jumps:
http://search.cpan.org/~drolsky/DateTime-1.12/lib/DateTime/LeapSecond.pm

This particular library is useful if you need to know the correct delta
time between UTC timestamps but have chosen to ignore the ambiguity problem
of correctly marking the leapsecond itself.

The "newest announced leap second" is not in the table of leapseconds built
into the code yet, but it's a simple matter to add it (cut and paste from
the IPERS).

Tim.
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