[tz] Reason for removal of several TZ abbreviations

[Guy Harris]

On Dec 6, 2017, at 8:50 AM, Brian Inglis <Brian.Inglis at systematicsw.ab.ca> wrote:

> On 2017-12-05 14:29, Guy Harris wrote:
> 
>> So, for doing a script to do the equivalent of what macOS and iOS do, you'd
>> want more like "get your external IP address, geolocate it, and hand it to a
>> program with a set of shapefiles for tzdb regions". See, for example
>> 	https://github.com/evansiroky/timezone-boundary-builder
>> (to which
>> 	http://efele.net/maps/tz/world/
>> now refers people).
> 
> More likely query the underlying geodatabase for the time zone region, often
> indexed by the minimum bounding rectangle [min x, min y[ - [max x, max y]
> surrounding the possibly non-convex hull, then resolve muiltiple hits by
> checking the interior convex polygons contain the coordinate, or equivalent tests.

That's what I meant by "hand it to a program with a set of shapefiles for tzdb regions".