[LEAPSECS] The relation between calendars and leap seconds.

[Tony Finch]

On Wed, 12 Nov 2008, Rob Seaman wrote:

>

> However, surely the point of coupling TI with the zoneinfo notion - just for

> the sake of argument - is to simply start distributing TI instead of UTC.

> Then UTC - a flavor of Universal Time, an alias for Greenwich Mean Time (which

> as you say is far from "eradicated") - remains available for those who need

> it.

>

> The adoption of TI would be massive and immediate.


If you simply do that then civil time will de facto diverge from UT, since
nobody will be applying the TI-UTC offset to the time broadcasts.

Remember that (as previously discussed on this list) you can't simply
redefine time_t to be TI and fix up the difference using zoneinfo. This is
because plenty of software doesn't use zoneinfo for time computations, and
instead relies on the POSIX specification that time_t is roughly UT.

You have for many years been able to configure the tz code (and therefore
many unix systems) to run with time_t following TAI and with the TAI-UTC
fixup in the zoneinfo code, just like the proposed TI setup. No-one runs
it this way because it isn't conforming and therefore isn't compatible
with a lot of code.

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/
FORTIES CROMARTY FORTH TYNE DOGGER: NORTHWEST 4 OR 5, OCCASIONALLY 6 AT FIRST,
BACKING SOUTHWEST 5 TO 7 LATER. MODERATE. SHOWERS THEN RAIN. MODERATE OR GOOD.