Time zone confusion and implementation hints

[lennox at cs.columbia.edu]

On Tuesday, July 6 2010, "Yves Goergen" wrote to "tz at lecserver.nci.nih.gov" saying:

> > If you need to support older filesystems, e.g. FAT32, you could alternately
> > map link() to CopyFile instead.
> 
> What does zic use links for? Does it link zone aliases? I think I won't
> need them in my calendar application, do I? Could I disable creating
> duplicate files (or linking them)?

Other than the default timezone (which doesn't make much sense to set on
Windows), links correspond exactly to Link lines in the tzdata source files.

Most of these do indeed come from the "backward" file, which you can
probably safely omit, but some of them are for cases where two separate
countries (by the ISO 3166 definition) have had identical timezone histories
since 1970.

You could probably get away with requiring people in Vatican City to use
Europe/Rome, or those on the isle of Guernsey to use Europe/London.
However, forcing people in the other countries of the former Yugoslavia to
use Serbian time, or Slovaks to use Czech time, is sufficiently politically
fraught that it's probably a lot less trouble in the long run just to get
links working.

-- 
Jonathan Lennox
lennox at cs.columbia.edu