variations on GMT-8:00

Paul Eggert eggert at CS.UCLA.EDU
Fri Jan 19 00:35:29 UTC 2007

Curtis Doty <Curtis at> writes:

> Why this discrepancy between PST8PDT and the equivalent geographically 
> named zones that use PST?

They're not geographically equivalent, since, for example,
Seattle and Los Angeles used different rules before 1970.

The PST8PDT rule is just a historical revenant, dating
back to when the tz database was done a different way.
It's not worth worrying much about.  As a practical matter,
we don't want it to be a link to Los Angeles because,
as the northamerica file says,

# We do these as separate Zones rather than as Links to avoid problems if
# a particular place changes whether it observes DST.

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