Is there a list of "current" time zones?

[Tim Klein]

I'm new here.  As I look through the tz database, and the archives of 
this mailing list, I realize what a phenomenal effort you folks have 
put in, to make all of this information available.  Thank you for all 
you've done!

A question...

I'm helping to write an application that needs a menu for the user to 
choose what time zone they live in.  With ~400 time zones in the 
database, that'd be a pretty daunting pull-down menu.

But as I understand it, a significant fraction of the ~400 time zones 
exist only for historical reasons.  Since our application will deal 
only with current and future times, historical distinctions don't 
matter, and we'd like the menu to show only the subset of time zones 
that are currently "in effect".  (And we don't mind if it isn't 
painstakingly accurate or updated in real time.)

Has anyone created such a list?  Or maybe an algorithm (if not code) 
for generating one from the full database?

I see that this question has come up in the past.  To quote from the 
archives...

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>From: "Andy Lipscomb" <AndyLipscomb at decosimo.com>
>Perhaps a better term would be "historical" time zones. This would 
>in fact be a useful distinction, since only a relatively small 
>subset of the timezones are necessary for applications that look 
>only forward--these would be the first set to present to a user for 
>selecting a time zone, with a "show all" option to get the complete 
>list. (For example, the 50 United States can be covered on a 
>forward-looking basis by eight zones--New York, Chicago, Denver, 
>Phoenix, Los Angeles, Anchorage, Adak, and Honolulu. And if one 
>takes as irrevocable the power of the EU over DST dates, then--for 
>example--London, Paris, and Helsinki would cover that entire area, 
>except for the different abbreviations used in the three +0 
>countries.)

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And...

>From: Paul Eggert [mailto:eggert at CS.UCLA.EDU]
>Sent: November 6, 2006 12:13 PM
>
>>  Is there any way to flag some of the old historical zones such that
>>  they don't appear when running "tzselect"?
>
>We could have a table for people who don't care about historical 
>times, which maps zone names to "modern" zone names, and tzselect 
>could have an option to use that table.

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Thank you very much for any wisdom on this subject!

Tim Klein
Dallas, Texas, USA