[tz] re : Time zones in Ukraine

Robert Elz kre at munnari.OZ.AU
Thu Apr 17 18:57:25 UTC 2014

    Date:        Thu, 17 Apr 2014 13:04:57 -0400
    From:        random832 at fastmail.us
    Message-ID:  <1397754297.16395.107638265.57E3EC20 at webmail.messagingengine.com>

  | This entire conversation is predicated on the assumption that we want to
  | display it in local time.

Probably, yes.

  | If there is a correct answer, then the
  | timezone the file was created in is a better candidate than the timezone
  | your current geographic location

Not at all, I have lots of files I created in Australia, but when I
look at them now, it is perfectly OK to show them in my current timezone.

The files all have UTC timestamps, so that actual times for when they
were last modified, or accesses (or whatever the filesystem provides)
are accurate, so when I see the times in my current local time, I know
when they were actually modified.   If I got shown some files in Australian
times (and in various US times if the file happened to have been last
touched when I was there for a while) or perhaps European timestamps, I'd
never have any idea what was up - I'd have to actually remember where I 
happened to be when I last touched the file in question - and since we're
talking about files that are 15-20 years old (or more), the chances of that
are negligible.

  | Rejecting the assumption makes the _entire_ exercise
  | irrelevant, not only the part I brought up.

Not at all.   And in any case, if you did want files displayed in whatever
happened to be the local time in the place where they were created, then
the data to make that happen would be extra information (location, or zone,
attached to every file).   That's not our business.   We don't do that,
nor do we advocate, nor denigrate any system that does.  None of our business.

What we do do here is collect the timezone data, as accurately as we can,
so people who do have a use for it, can use it in whatever way is appropriate
to the system and applications that they have.

Whether or not you happen to have a need for some of that is irrelevant, just
as it is whether I do.   Collecting all of the data, as accurately as
possible, at least starting from our current epoch, is the objective.

The epoch is currently Jan 1, 1970 (midnight, UTC) - not a surprising
choice, as originally this project was for unix (later posix) timestamps,
and as that's the epoch of those timestamps, (and = just slightly - predates
the birth of unix,) there can't logically be anything earlier.

Of course, these days, the scope of the project has expanded. it isn't
limited to just unix/posix timestamps any more, and with that, it would be
reasonable to push the epoch back earlier - personally I'd like to see that
happen, gradually.   Not everyone agrees - partly simply for the pragmatic
reason that getting accurate data on what the times were used as we move
further back gets increasingly harder, and second, because the number of
timezones we would end up with would increase (were we to go back before the
introduction of standardised time - which even I don't think would be useful - 
we'd need to have a different zone for everywhere on the planet, perhaps for
every house, but certainly for every town and village).  Notwithstanding that,
if possible, and as the data to do it is located, I'd quite like to aim for
at least moving the epoch back to the start of the 20th century.  If that
happens, lots more or what you consider "useless" zones would appear...


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