Re: POSIX TS spec reverses the meaning of TZ offset compared to ISO

[Heinz Tuechler]

Max Nikulin wrote/hat geschrieben on/am 02.02.2023 04:22:
> On 02/02/2023 04:57, Heinz Tuechler wrote:
> > My impression is that many of non experts like me don't
> > know in which time zone they are living.
>
> For you own time zone: Open Development tools in a browser ([F12]),
> switch to console, type
>
>      new Intl.DateTimeFormat().resolvedOptions().timeZone

Thank you, Max.
It seems to me that this shows the time zone I selected at set up of the
computer, in my case Europe/Berlin. Using package lutz in R with correct
coordinates I see Europe/Vienna, based on open street map.
Days ago I did not even know that Berlin and Vienna are in different
time zones.

> I am sure there are a lot of web pages that do the same.
>
> On linux you can use the following tool
>
>     timedatectl
>
> Unfortunately Emacs does not have API to obtain time zone identifier,
> only offset and abbreviation are exposed by GNU libc. POSIX does not
> have such requirement.
>
> > Is it trivial to find the [continent/city] timezone name to a specific
> > place?
>
> For other places: since data to build time zone map are available, there
> should be web sites that allows to find identifier for any location.
> Sorry, I do not use them, so I can not recommend a particular one.
>
> An application that is able to read locally installed tzdata may assist
> by filtering the list by time offset or by the continent (or the ocean,
> see e.g. Pacific/Apia trips across the International date line to
> America and back to Asia with Australia).