[tz] Please include Montreal

Guy Harris guy at alum.mit.edu
Tue Nov 14 04:08:29 UTC 2017

On Nov 13, 2017, at 7:28 PM, Phake Nick <c933103 at gmail.com> wrote:

> There are github.com/evansiroky/timezone-boundary-builder that do this.

Where "this" is "shapefiles to let you find the tzdb zone corresponding to a particular longitude and latitude".


provides lists of cities containing:


geonameid         : integer id of record in geonames database
name              : name of geographical point (utf8) varchar(200)
asciiname         : name of geographical point in plain ascii characters, varchar(200)
alternatenames    : alternatenames, comma separated, ascii names automatically transliterated, convenience attribute from alternatename table, varchar(10000)
latitude          : latitude in decimal degrees (wgs84)
longitude         : longitude in decimal degrees (wgs84)
feature class     : see http://www.geonames.org/export/codes.html, char(1)
feature code      : see http://www.geonames.org/export/codes.html, varchar(10)
country code      : ISO-3166 2-letter country code, 2 characters
cc2               : alternate country codes, comma separated, ISO-3166 2-letter country code, 200 characters
admin1 code       : fipscode (subject to change to iso code), see exceptions below, see file admin1Codes.txt for display names of this code; varchar(20)
admin2 code       : code for the second administrative division, a county in the US, see file admin2Codes.txt; varchar(80) 
admin3 code       : code for third level administrative division, varchar(20)
admin4 code       : code for fourth level administrative division, varchar(20)
population        : bigint (8 byte int) 
elevation         : in meters, integer
dem               : digital elevation model, srtm3 or gtopo30, average elevation of 3''x3'' (ca 90mx90m) or 30''x30'' (ca 900mx900m) area in meters, integer. srtm processed by cgiar/ciat.
timezone          : the iana timezone id (see file timeZone.txt) varchar(40)

The latter of those should actually be sufficient, I think, for a system that *doesn't* track your location and update the current time zone in real time.  ("In real time" in macOS/iOS/etc. includes a mechanism to update the current tzdb zone *of running processes*, so processes don't have to be restarted while you're in transit or when you get off the plane/train/bus/etc. in a different time zone; I don't think any other UN*Xes do that.)

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