Re: POSIX TS spec reverses the meaning of TZ offset compared to ISO (was: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda)

[Ihor Radchenko]

Max Nikulin <manikulin@gmail.com> writes:

>> Because `encode-time' accepts POSIX TZ as argument. So, may as well.
>> Note that Etc/GMT-8 is also accepted as POSIX TZ.
>
> "May" does not assume "should".

It will be easier to implement POSIX TZ compared to limiting it to TZDB.
We have no way to know if a given string is a valid TZDB entry to not.

> The disappointing issue with POSIX syntax is the case of decision of 
> authorities to change time zone offset. It is neither regular DST rule 
> nor constant offset. The result is incorrect mapping between UTC and 
> local time.

We cannot do much about it, AFAIU. Maximum is trying to do feature
request in glibc, but I assume that they know about this issue.

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
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