AndyLipscomb at decosimo.com
Mon Jun 26 18:21:24 UTC 2006
"Zhe Su" <james.su at gmail.com> writes:
> Actually those are legacy timezones which are not used anymore.
Yes, if you don't care about pre-1980 time stamps, then you can use TZ='Asia/Shanghai', or even TZ='CST-8' on POSIX hosts.
However, if you do care about old time stamps, then Asia/Harbin etc. are not "legacy", because they have a practical difference for programs running on today's computers.
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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