
Timezones
*********

Getting localized time right, seems to be the most difficult part
about calendaring (and messing it up ends in missing the one imported
meeting of the week). So I'll briefly describe here, how khal tries to
handle timezone information, which information it can handle and which
it can't.

All datetimes are saved to the local database as UTC Time. Datetimes
that are already UTC Time, e.g. "19980119T070000Z" are saved as such.
Datetimes in local time and with a time zone reference that khal can
understand (Olson database) are converted to UTC and than saved, e.g.
"TZID=America/New_York:19980119T020000".  Floating times, e.g.
"19980118T230000" (datetimes which are neither UTC nor have a timezone
specified) are treated as if the *default timezone* (specified in
khal's config file) was specified. Datetimes with a specified timezone
that khal does not understand are treated as if they were floating
time.

khal expects you want *all* start and end dates displayed in *local
time* (which can be configured in the config file).

"VTIMEZONE" components of calendars are totally ignored at the moment,
as are daylight saving times, instead it assumes that the TZID of
DTSTART and DTEND properties are valid OlsonDB values, e.g.
America/New_York (seems to be the default for at least the calendar
applications I tend to use).

To summarize: as long as you are always in the same timezone and your
calendar is, too, khal probably shows the right start and end times.
Otherwise: Good Luck!

Seriously: be careful when changing timezones and do check if khal
shows the correct times anyway (and please report back if it doesn't).
