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Re: [Sedate] Can offsets like [+02:00] be used instead of IANA names in brackets?

Paul Eggert <eggert@cs.ucla.edu> Fri, 18 March 2022 20:01 UTC

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From: Paul Eggert <eggert@cs.ucla.edu>
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Subject: Re: [Sedate] Can offsets like [+02:00] be used instead of IANA names in brackets?
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On 3/17/22 19:22, Michael Douglass wrote:
> Paul - would you like to respond to the last question below on tzdb 
> identifiers?...

> -------- Forwarded Message --------
> Date:     Thu, 17 Mar 2022 18:14:27 -0700
> From:     Justin Grant <justingrant.ietf.public@gmail.com>
> ...
> I don't know if the TZDB identifiers are included in any standard. 

As TZDB itself says in 
<https://data.iana.org/time-zones/tz-link.html#changes>, "The tz code 
and data are by no means authoritative."

Even now, a TZDB name like "Asia/Hebron" doesn't uniquely specify the 
mapping from UTC to local time; you also need a TZDB version string like 
"2022a", because the data for Asia/Hebron changed in 2022a vs the 
previous version.

Also, I know of at least two efforts to fork TZDB, though none have 
published official versions yet. If and when that happens, you may also 
need to specify the source for your TZDB data to specify what the 
mapping is.

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