[tz] Converting from individual cities/states/country names to Windows time zone names

Daniel White twinbee42 at skytopia.com
Mon Dec 5 17:18:20 UTC 2011

Hi all, thanks for your help,

If it's okay, I'll answer to all of you in this one email.

> http://efele.net/maps/tz/world/

I looked inside the download, and there seemed like nothing like a concise one 
to one mapping unfortunately.

> Perhaps the "zone.tab" file distributed as part of tzdata would be 
> useful.
> You could search for the country code in the first column, or 
> search for nearby latitude/longitude in the second column, or 
> both, and then display a menu of a few likely choices.

I don't think this is suitable, since many such as Canada have 6 time zones 
(okay I can live with that), but many famous states and cities aren't 
represented at all from what I can tell.

> There is one at http://download.geonames.org/export/dump/ (by country, 
> it's a lot of data).

Certainly. I only want the most famous places, something closer to around 
100k-200k filesize at the most (as my calc is only around 300k itself). If it 
means I have to filter yet another stage, then so be it, but then I would need 
to hunt for a list of the '1000 most well known places' (or similar) in the 

So it looks like back to the drawing board. I appreciate the help, but I find 
it rather surprising that something like this doesn't already exist. Just to 
say something like "London 3pm in New York" sounds like a very common thing to 
want. You'd think a lot of people would find such a database very useful. Am I 
mistaken here?

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