[ntp:questions] How to get uclibc style timezone string (e.g GMT+0IST-1, M3.5.0/01:00:00, M10.5.0/02:00:00) from javascript

David Woolley david at ex.djwhome.demon.co.uk.invalid
Mon Jul 7 07:12:51 UTC 2008

Rohit wrote:
>> Whether you can even do this, and if so whether the result will be valid
>> beyond the Autumn, depends on your operating system and country.
> Will you elaborate bit more on this.
To be able to do it you need an OS that has timezone support with at 
least equivalent capability.

You also need to be in a country that: has only two DST states.

You also need to be in a country that sets rules algorithmically. 
Whilst the UK now uses a week 5 rule, it wasn't that long ago that the 
rules were set by secondary legislation each year, and generally 
differed from those in the primary legislation.  More recently, Pakistan 
introduced DST with only two weeks notice, and appear to have only done 
it for one year.  Even the best maintained site would have said there 
was no DST if you ran the algoritthm before the middle of May, and most 
probably wouldn't give the right result until some time in the middle of 
June.  The resulting rule would not be valid from June next year, unless 
new legislation is introduced.  The rule is probably an Mn.0.1 rule, but 
one can only guess that from a sample of one.

Windows only has similar capability to uclib, so, where there aren't 
compatible algorithms, you can only find a solution for the two 
transitions that are in the current Windows data.

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