[LEAPSECS] Standards of time zones -Brooks Harris

[Steve Allen]

On Thu 2014-01-09T21:57:49 -0800, Hal Murray hath writ:

> The fundamental problem with POSIX timekeeping is that it pretends that leap seconds don't exist.


While insisting that time_t match UTC, and I think not because of the
name UTC per se, and not because POSIX loves mean solar days, but
rather because that happens to be the name currently associated with
radio brodcast time signals.

My impression is that there are too many POSIX systems which have
based their time_t on the radio broadcast time signals, therefore the
only option for POSIX is to recommend that time_t match that time
scale, whatever it happens to mean or be called.


> What would you like for an API if you were starting over and wanted

> to support leap seconds?


I have asserted that POSIX does not want to know astronomy, does not
want to track geophysics, that POSIX really wants to count atomic days
rather than mean solar days, and that they have already specified
enough other pieces of the OS that they could hide the difference in
the zoneinfo/tzdata/tzcode.


> What would you have to change in the OS and libraries?


Pretty much nothing, it's all implemented and distributed already.
It has been tested and anyone who wants can perform more tests
without need for special equipment.

http://www.ucolick.org/~sla/leapsecs/right+gps.html

That's my compromise.  Every second is of equal SI duration to make
the realtime systems happy, and every civil day remains just the way
things are now -- based on actually observing the earth rotating.

--
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