proposed change to 'zic' to support "outlandish" offsets

Olson, Arthur David (NIH/NCI) [E] olsona at
Tue May 1 13:37:59 UTC 2007

I don't know about Mt. Athos in particular; the general case of trying
to support Julian dates is complicated by needing to change the
day-of-month associated with a time_t value without changing the
day-of-week associated with the value.

The advent of the 64-bit time_t extends the range of time_t values to
include historical periods when the Julian calendar was in effect. It
may or may not be worthwhile to try to change the handling of Julian-era
time_t values; doing so would seem to require changes to both zic and to


-----Original Message-----
From: Paul Eggert [mailto:eggert at] 
Sent: Monday, April 23, 2007 6:37 PM
To: tz at
Cc: mgpeter at; evdokimos at
Subject: proposed change to 'zic' to support "outlandish" offsets

Currently zic allows only GMT offsets in the range -24:00 to 24:00.
And yet the recent query about Mt. Athos led me to think that in some
cases it can be useful to allow GMT offsets outside the range, to
approximate the Julian calendar.  And at any rate zic should be able
to generate whatever offset can be stored in the standard tz file
format, if only for testing purposes.

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