[ntp:questions] Leap second to be introduced in June

William Unruh unruh at invalid.ca
Fri Jan 16 09:44:51 UTC 2015

On 2015-01-16, Chris Adams <cmadams at cmadams.net> wrote:
> Once upon a time, Phil W Lee  <phil at lee-family.me.uk> said:
>>For the tiny number of programs which really need UTC (not TAI), it
>>would just be a different number, but the only thing I know of which
>>really needs UTC rather than TAI would be programs to assist with
>>astronomy or astral navigation.
> I think one problem with OS clocks in TAI is that counting it correctly
> requires active/on-going maintenance at unknownable intervals for all
> systems that use any form of timestamps (including for example anything
> that uses network file systems).
> Also, you can't properly represent future timestamps (necessary for some
> things) as seconds since an epoch, and that's pretty widely used.  By
> that I mean that the number of seconds between 2015-06-30 23:59:00 and
> 2015-07-01 00:00:00 has changed since last month.

If those are supposed to be UTC times then the number of utc seconds has
not changed. The number of TAI seconds has ( and if you counted each
second as it occured, it will also be diffeent than if a leapsecond had
not been inserted).


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