Poul-Henning Kamp wrote on 2005-01-23 09:00 UTC:
> >any "leap
> >hours" that prevented this would, if ever implemented, be even more
> >traumatic than leap seconds are now.
>
> they already happen here twice a year, and by now even
> Microsoft has gotten it right.
OBJECTION, your Time Lords!
UTC currently certainly has *no* two 1-h leaps every year. What the
witness tries here is merely a poor attept to confuse the jury. He
muddles the distinction between local civilian time, which we all know
is entirely subject to our politicians deep-seated desires to manipulate
us into getting out of bed earlier in summer, and UTC, which is what all
modern computers use internally for time keeping today, below the user
interface, where a 1-h leap is entirely unprecedented and uncalled for.
[By the way, and for the record, may I remind the jury that the quoted
Microsoft *is* actually the one large operating-system vendor who still
has not quite yet "gotten it right", as all Windows variants still
insist on approximating in the PC BIOS clock LCT instead of UTC.
Rebooting during the repeat hour after DST *will* corrupt your PC's
clock. Gory details: http:// www.cl.cam.ac.uk/~mgk25/mswish/ut-rtc.html ]
> >In addition to being historically unprecedented, such a move would be
> >illegal in the United States and some other countries, which have
> >laws explicitly defining their time zones based on solar mean time,
> >unless such laws were changed.
>
> The laws, wisely, do not say how close to solar mean time, and parts
> of USA already have offsets close to or exceeding one hour anyway.
As Ron Beard said wisely in his opening address in Torino, laws can be
changed fairly easily, and this discussion should certainly not be about
reinterpreting *past* legislation. Instead, it should be entirely about
making a scientific, technical, and practical recommendation for
*future* legislation.
If you read, just one example, to deviate a bit from the overwhelmingly
US/UK-centricism of this legal argument, the relevant German legislation,
http://www.cl.cam.ac.uk/~mgk25/time/zeitgesetz.en.html
then you will find that it consists at the moment simply of a pretty
exact technical description of UTC. In other words, it follows exactly
the relevant ITU recommendation! If the ITU recommendation were changed,
for a good cause and with wide international consensus, I have little
doubt that the German parliament and pretty much every other parliament
would be sympathetic and update the national legislation accordingly.
German laws are already updated almost each time the BIPM revises some
aspect of the SI. Countries update their national radio interference and
spectrum management legislation regularly based on the international
consensus that is being negotiated within the ITU. The US and UK are
actually no different from that, except that the subtle differences
between GMT and UTC have escaped political attention in these two
countries so far, and as a result, they still have a technically rather
vague definition of time in their law books, and leave in practice all
the details up to the Time Geeks as USNO, NPL, etc.
If you think that discussions within the ITU should feel constrained by
the legislation of individual member countries, as opposed to setting
guidelines for future legislation there, then you have simply
misunderstood the entire purpose of the process.
Markus
--
Markus Kuhn, Computer Lab, Univ of Cambridge, GB
http://www.cl.cam.ac.uk/~mgk25/ | __oo_O..O_oo__
Received on Sun Jan 23 2005 - 06:33:52 PST