[tz] Patched file australasia - time point unique abbreviations for Australia

Tobias Conradi tobias.conradi at gmail.com
Mon Apr 8 22:06:38 UTC 2013

Thanks for the feedback.
On Mon, Apr 8, 2013 at 10:52 PM, David Grosz <david at dlg.com.au> wrote:
> I don't suggest to be an authority on this subject but I wish to discuss
> three points:
> 1. I don't particular like the 'H' for half-hour daylight saving.  Whether
> it's 30 minutes or 60 minutes, it's still daylight saving so I think only a
> 'D' is necessary.
Imagine one year it is 60 and the following it is 30, then it may help
to point people to the fact that the offsets differ. In the southern
hemisphere two DST-periods can exist in the same year. There may also
be cases where both offsets exist at the same time. So I took a more
global approach, trying to define meanings for the letters preceding
the final T.

I now made a list at http://anna.info/wiki/IANA_time_zone_database
documenting IANA usage.

letters preceding final T, sometimes have one of these meanings:
D = Daylight Saving
S = Standard, sometimes Summer
W = War (northamerica file)
P = Peace (northamerica file)
M = Mean (europe file: MMT # Moscow Mean Time)
M = Midsummer (europe file: Moscow - M # Midsummer, also for Spain,
France, Germany/SovietZone)

two letters preceding final T sometimes have one of these meanings:
DS = Double Summer (europe file: MDST # Moscow Double Summer Time,
BDST - British Double Summer Time)
LM = Local Mean

My proposals would be
S = never Summer, only Standard
M = never mean, only Midsummer (save 2 hours)
L = Local

> 2. For Lord Howe's daylight saving time, could we just report AEDT as it's
> the same time as Sydney, Canberra, etc?
Oh yes. Will have to look how to do this. That would also eliminate H
= Half hour saving. LH specific DST code would be needed for 1981 to
1984 when saving was one hour.

> 3. Shouldn't we just stick to CW (Central West) instead of naming the zone
> to do with the town in the zone?
So it is done. The other was just a proposal for international format
standardization. This won't be in the patch.

Tobias Conradi
Rheinsberger Str. 18
10115 Berlin


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