Jan Bottorff <janb at pmatrix.com> wrote:
> I have no idea what to do about calculating correct UTC time into the
> future, as you don't really know what the leap second adjustments will be
> until they come near. How often leap seconds happen is influenced by the
> earth rotation speed, which changes based on temperature and such things.
> Because of this, I am convinced making your systemwide time reference be
> UTC time is a terrible idea (this is what WinNT is supposed to do).
> 

Good point, UTC has problems with future dates.  It's also been pointed
out that it has problems with dates way in the past.

However, for reporting the *present* time from the OS to Squeak, UTC
might well be the best thing:

	- probably any OS that knows about timezones at all, knows about UTC. 
Thus, UTC is easy to implement

	- If you need to do precise calculations, you can convert between UTC
and, eg, TAI for *present* time values, even though you can't do so for
time values far in the past or future.

	- UTC and timezones derived from it (EDT, PDT, etc) are the ones of
choice for many applications.  It's not only good enough, but more
correct in these cases.  (Although most such apps don't care about
sub-minute precision)


Lex