use Date::Manip::TZdata; $tzd = new Date::Manip::TZdata($dir);
This module consists of routines for working with the tzdata files. These files are updated several times a year and are the basis for time zone descriptions for most computer systems.
use Date::Manip::TZdata; $tzd = new Date::Manip::TZdata($dir);
This finds and reads in all the tzdata. If $dir is passed in, it is the directory where a tzdata directory is located. It defaults to the current directory.
When a time change occurs, the time may change backwards or forwards. Time changes rules are listed on a per-year basis. It is assumed that time changes will not occur so close to the end or start of the year as to cross the year boundary (in other words, the year will not change as a result of the time change). This is not accounted for, and it is hoped that this situation will never occur.
Also, because this module is strictly limited to 4 digit positive years (regardless of whether it is wall clock or universal time), and because various parts of the module switch back and forth, valid times for this module are from Jan 2, 0001 to Dec 30, 9999. This ensures that conversions from wall clock to universal or vice versa will never make dates occur in the year 0000 or 10000.