[tz] [PROPOSED] Be more consistent about UT vs UTC
eggert at cs.ucla.edu
Tue Nov 7 21:39:38 UTC 2017
On 11/07/2017 10:01 AM, Philip Paeps wrote:
> Explaining / apologising for our ancestors seems wise though. Perhaps
> a more prominent note somewhere for the uninitiated?
I'm hoping that the bullet point in theory.html suffices; I mean the one
that says "In the tz database commentary, UT denotes a family of time
standards that includes Coordinated Universal Time (UTC)...." If this
wording could be improved or if featuring it more prominently would
help, specific suggestions are welcome.
Before the recent change, tzdb was inconsistent; although quite a bit
already respected the distinction between UT and UTC, quite a bit
didn't. The idea of the patch was to change tzdb to follow the bullet
point more systematically.
> I wonder if it wouldn't be easier to simply note "where we write UTC,
> we actually mean UT when referring to timestamps before UTC was
Something like that was proposed more generally, even for applications
outside tzdb, here:
Sauter J. Extending Coordinated Universal Time to dates before 1972.
Sauter also suggested that we drop the use of time_t for telling time:
Sauter J. Avoid using POSIX time_t for telling time. 2017-10-08.
If these recent proposals catch on, I suppose we could change tzdb
eventually. Dropping time_t would be a big change, though. Even
extending UTC for old timestamps is a stretch.
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