[LEAPSECS] Leap seconds have a larger context than POSIX

[Steve Allen]

On Sun 2020-02-02T00:33:08+0100 Warner Losh hath writ:
>  It's the fact that things like filesystems
> specify an elapsed time since an epoch in a time scale without leap
> seconds. Every FAT or NTFS disk around has a time like this.

Beginning 2018-06-01 the value of Microsoft Windows FILETIME ceases to
be seconds of UT since 1600 and begins to be (TAI - 37 s).
Microsoft has decided to become the authoritative point of
distribution for the leap second information that no international
agency has ever been tasked to be.

> Replacing steering systems
> for telescopes is likely somewhat less than that.

I have already written up how it is not an insurmountable problem for
telescope systems, but digging deep into the literature from around
1970 even further invalidates any notion that leap seconds are for
astronomers.

In the many meetings and recommendations there were several instances
where the participants and wording recognized the requests from
astronomers to preserve UT.  In every instance where a document
specified a maximum deviation that agreement was later violated.  In
one case it was broken specifically because a high official at CCIR
conceded to a high official from USSR and directed the BIH to violate
the wording of the existing agreement.

The leap seconds were included in the CCIR recommendation not because
of anything any astronomer said, but because a few of the participants
in the CCIR process understood that they did not have the legal
authority to cause all nations to change calendar days from mean solar
days to atomic days.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
1156 High Street               Voice: +1 831 459 3046         Lng -122.06015
Santa Cruz, CA 95064           https://www.ucolick.org/~sla/  Hgt +250 m