Re: [Emailcore] WGLC: draft-ietf-emailcore-rfc5322bis-03

[Steffen Nurpmeso <[e-mail]>]

Hello.

(Replying to Msg-Id copied from mail archive.)

For the MUA i maintain i have a user request regarding timezone
usage, and reading the according paragraph in the above document
i thought maybe a clarification or guidance may be a good thing to
improve the situation in the future in general.

The user uses a TAI timezone locally, a timezone where the offset
from UTC has second precision.  This is a quite common situation
for at least past timezones, too:

  $ grep -A0 -E '[[:digit:]]+:[[:digit:]]+:[[:digit:]]+' \
      /usr/share/zoneinfo/tzdata.zi | grep -v -- -- | wc -l
  410

The user wants me to forcefully overwrite the local timezone
and instead use UTC in cases where second precision is required,
as RFC 5322 only supports minute precision, and when looking at
the generated message again the date is of course wrong.
The same user made an identical request to the exim MTA in 2020,
and they seem to follow it, at least in parts.  They simply switch
to UTC, whereas i thought the following would apply better:

  Though "-0000" also indicates Universal Time, it is used to
  indicate that the time was generated on a system that may be in
  a local time zone other than Universal Time and that the
  date-time contains no information about the local time zone.

Maybe the standard should explicitly mention the above approach
for all timezones which require second precision not to loose the
correct timestamp?

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)