[tz] Introduce Etc/UTC+x timezones?

Guy Harris gharris at sonic.net
Fri Apr 21 22:02:58 UTC 2023


On Apr 21, 2023, at 12:45 PM, Paul Gilmartin via tz <tz at iana.org> wrote:

> On 4/21/23 13:12:21, Derick Rethans via tz wrote:
> 
>> In PHP we actively discourage people using these Etc/GMT zones, as they're not actually zones, but fixed offsets . They're often just temporary place holders for the offset at some time during the year. And we're of the opinion that they shouldn't be used in user facing interfaces at all.
> 
> Be practical.  Suppose I and colleagues in Canberra want to arrange a series
> of E-conferences at mutually convenient tines. How should I describe my
> timezone:
>    MST7MDT,M3.2.0,M11.1.0?
>    /America/Denver?
>    40°00′54″N 105°16′14″W?
>    ... ?

If they have tools that support a proper UI for selecting tzdb regions, tell them your location and, if the UI doesn't recognize Suffolk, Montana or wherever you are, give them the location of a nearby city large enough to be notable.

Otherwise, either:

	If all of the conferences will take place when Daylight Saving Time is in effect in the US, describe it as "currently, 6 hours west of UTC".

	If all of the conferences will take place when Daylight Saving Time is not in effect in the US, describe it as "currently, 7 hours west of UTC".

	If some will take place when it's in effect and some won't, describe it as "currently, 6 hours west of UTC, but after 2023-11-04, it will be 7 hours west of UTC".

or, if they have tools that support a crappy UI that exposes tzids, give them America/Denver, ask them what software they're using, and complain to the vendor of the software that they should do a better job.  (There are various projects that can help, such as OpenStreetMap and the "shape files of tzdb regions" project, but it'd be nice if there were easier ways for tzdb users to find and use them.)

> what tools should I assume they have?

Either 1) the ones that they said they have when you asked them or 2) just their appointment calendars.


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