[tz] Ambiguous abbreviations for Australian timezones when daylight savings is in affect

Robert Elz kre at munnari.OZ.AU
Tue Apr 2 05:27:57 UTC 2013

    Date:        Tue, 2 Apr 2013 00:37:22 +0200
    From:        Tobias Conradi <tobias.conradi at gmail.com>
    Message-ID:  <CAAGevbU8J8j5PMPDXedegWdNBO+OXSUaFbguSchwTZW=rGyS2Q at mail.gmail.com>

  | Thanks for the confirmation that your answer didn't relate much to the
  | question why there is EST in the IANA timezone database..

Because it was reviously answered - they're there because the API requires
acronyms.  What's more, at the time when the Aust acronyms were chosen (which
was well before ado created the tzcode & tzdata) it seemed likely that the
acronyms were required to be 3 letters exactly (nothing else had ever been
used, and it was unknown what software might be assuming 3 (upper case ascii)

As to why the actual value EST is used, it is because (at least) the
Victorian legislation (and it is Victoria where these acronyms were first
inserted into unix systems for Aust - that eventually moved them into
tzdata) the legislation contains the names "Eastern Standard Time" and
"Eastern Summer Time".   If you cannot see from that where "EST" comes
from (twice) then you (and even more, those who have to care for you on
a daily basis) have my sympathy.

  | > Abbreviations are not needed at all,
  | Timothy showed otherwise.

No, he asserted they were, he showed nothing - for the purposes
he claimed to be using them, the acronyms (or any other zone information)
are just useless.

  | > Because the commonwealth govt is not responsible for time in Aust,
  | Mr. Elz, the thread is not about time in Australia but about acronyms.

The comonwealth govt in Aust is not responsible for anything  (outside ACT,
and perhaps NT) (time, acronyms, what you eat for breakfast ...) unless
either the Aust constitution, or some enabling delegation from one of the
state governments says it is so.

  | Weather forecasting has been given as a reason by Timothy to have
  | unambiguous acronyms.

And would you like to explain just how the timezone acronym alters whether
it is going to rain or not, or when, or how much (or any other weather event)?

  | > national measurement lab.
  | What do they have to do with time zone acronyms?

Absolutely nothing, which was the point.   But they are the agency that the
commonwealth (and the states) defer to for the definitions of various terms
and values used for purposes related to all kinds of measurement.  They define,
in Aust, how long a second is, what "gram" means, ... - if there were to be
an existing commonwealth agency that would be likely to have any responsibility
for this - other than as it specifically related to ACT or NT - then the NML
would most probably be the one that would be selected - just my opinion - but
the commonwealth have no power in this area, so no reason to delegate any
agency to undertake it, so unless something changes, we will never know.

  | It is a states responsibility to define unambiguous acronyms for the
  | Commonwealth?

No, it is nobody's responsibility to define unambiguous acronyms for anyone.

If you think otherwise, then please explain just where that responsibility
originates, and what the penalty is for failing, and who enforces that?
(True "responsibility" requires all of that.)

The states have no responsibility here (they could, if they wanted, define
acronyms for their own time zones, and could make those unambiguous, with
respect to other acronyms defined inside their own state, if they wanted,
but that's all, and they are certainly not required to do so, and have not).

There is no-one else, it certainly is not the commonwealth of Aust's
responsibility, they would be acting beyond their powers if they tried
(so aside from a few informational web pages, aimed at tourists, which no-one
with any knowledge would claim have any authority at all, they don't.)

Nor is it our responsibility, we just provide data that meets the requirements
of the API, which calls for an acronym to exist, but places very few
requirements on what that acronym actually is, and what requirements there are
all relate to its syntax, not at all to its value.

Now if you're thinking that that would make the acronym useless, and pointless,
then you're finally getting it.   And no, it is not our job to fix that, the
API is defined by POSIX, if you want the definition fixed, go complain to them,
not to us.

Personally I'd be quite happy (but please do not treat this as a request,
or even a serious suggestion, it is not) if we were to set all of the
acronyms, in all of the zones (in Aust and all other places) to ZZZ.


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