proposed time zone package changes

Dave Cantor Dave at
Mon Jul 13 15:24:35 UTC 2009

On 13-Jul-2009, Olson, Arthur David (NIH/NCI) wrote:

> In a "permanent DST" situation, a POSIX TZ string such as...
> ...can get almost everything right, but the tm_isdst indicator in tm
> structs will end up being set to zero.

Yes, that's true.   I consider this to be yet another effect of 
the fact that POSIX TZ strings cannot encode all the rules that 
people can legislate.   

Maybe we need a kludge like TZ=XST10XDST,J0,J999  to indicate 
that DST is in use all year.    That doesn't comply with POSIX, 
though, and using J1/0,J365/23:59:59  does, but implies 
transitions which do not occur.

What TZ string did people use in the United States in the 1973, 
when we stayed on DST all year?   Was Eastern Time specified as 
EDT4?   Did we have computers back then? :-)

Dave C.

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