[tz] TAI as a time zone?

Steve Allen sla at ucolick.org
Sun Sep 15 12:03:27 UTC 2013

On Sat 2013-09-14T23:59:53 -0700, Guy Harris hath writ:
> The *input* can either be a count of seconds that have elapsed since
> the Epoch or can be seconds-since-the-Epoch.  (Yes, the snarky tone is
> intended.)

I hesitantly point out that due to variations in national legislation
phrases like the number of "seconds that have elapsed since the Epoch"
is subject to variation between jurisdictions

The distinction between the "right" and POSIX flavors of tz
corresponds to the two extremes.  The "right" flavor counts the number
of second markers actually used in radio broadcast time signals
(effectively mean solar seconds before 1972 and atomic seconds after).
The POSIX flavor effectively counts mean solar seconds in order that
it can have 86400 in a civil day (which so far is mean solar).

So phrases like "seconds that have been broadcast according to
international radio regulations" may be useful for clarity.

Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
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