[tz] Ethiopia local time

[Paul.Koning at dell.com]

> On Sep 12, 2018, at 3:58 PM, Steve Allen <sla at ucolick.org> wrote:
> 
> On Tue 2018-09-11T22:23:01-0700 Paul Eggert hath writ:
>> I'm afraid not, as it's based on solar time.
> 
> The article gives the impression that it's not really solar because an
> hour of imprecision is culturally irrelevant, so it's really just 6
> hours different from what a cell phone says.  But even with that
> simplicity I don't think that tz should implement something without a
> much more authoritative and clear source for when the Ethiopian day
> begins.
> 
> --
> Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
> UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
> 1156 High Street               Voice: +1 831 459 3046         Lng -122.06015
> Santa Cruz, CA 95064           http://www.ucolick.org/~sla/   Hgt +250 m

That brings up an interesting question.

What does the TZ database mean "local time" to be?  Time in its common representation where zero is midnight and 12 o'clock is noon?  Or is it meant to account also for local conventions that zero is some point in the day different from midnight?

If the former, then this issue is out of scope.  If the latter, then it suggests there might be two Ethiopia zones, one for "midnight origin" (the one we have now) and one for "local convention" which combines the offsets from latitude, and the offset from the different convention of what the starting point is.

	paul