proposed tz data changes for Iran, Sri Lanka, Alberta, Thule, etc.

Paul Eggert eggert at CS.UCLA.EDU
Thu Mar 23 20:29:08 UTC 2006

Roozbeh Pournader <roozbeh at> writes:

> I would really prefer it if we could use IRT from now on, instead of

That is what we used to do (the British tradition), but in 2003 we
changed it to the American tradition after you wrote "I have also
changed the abbreviations to what is considered correct here in Iran,
IRST for regular time and IRDT for daylight saving time."

It would be confusing for the standard time zone abbreviation to
depend on whether daylight-saving time was potentially in use at some
other part of the year.  I'm not aware of this tradition occurring
elsewhere, and it sounds error-prone.  If the Iranian parliament
brings back daylight saving time in the future, will the abbreviations
revert back?  And when exactly would the abbreviation for standard
time change from "IRT" to "IRST"?

The simplest option is to do nothing, and to stick with "IRST"/"IRDT".

Another option is to undo the 2003 change, and revert back from the
American "IRST"/"IRDT" terminology to the British "IRT"/"IRST".  That
would cause current and future time stamps to use "IRT", as you
prefer, but it would cause past time stamps to use the British
tradition (which from what you say, is less common).

Are there any other options and/or opinions?

Anyway, this is not an urgent change, so it can wait until the next
batch of patches.

PS.  I noticed that
<> uses
"IST" to mean "Iran Standard Time" and either "IRT" or IRST to mean
"Iran Daylight Time".  Urk!  Can it get any more confusing that that?

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