Proposed 64-bit changes

Olson, Arthur David (NIH/NCI) olsona at
Mon May 2 13:46:29 UTC 2005

> Is it feasible for zic to encode variable information in the data file for
the last set of rules, that would be used for times past the last entry in
the transition table?  Then localtime()
> would use the variables algorithmically rather than using table-driven
data, for dates past the last table entry.  Perhaps set a minimum size for
the table entries (ie, have table entries
> at least up to year xxxx.)

This approach isn't as general as the extend-400-years approach. Take, for
example, the proposal a few years back to extend DST into November in the
Pacific Time Zone in presidential election years (as a way of minimizing
announced results from New York affecting voting in California). The
irregularities that would have resulted can't be handled by a POSIX-style
rule string; they can be handled by the extend-400-years approach.

> I'm not sure yet, but with 9x larger timezone binaries, Sun might retain
the old-style timezone binaries for timezone patch updates.
> If so, it might be useful if zic has an option to produce old-style
timezone binaries.

That's certainly doable. Note, though, that the new binary files start with
information in the old format, and should be usable on old systems.


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