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Notes on Time Zones

Notes on Time Zones
  1. The time zones (regions/place names) supported by the XSCF can be changed to support the latest time zone information.
    For any previously set time zone that the system cannot use anymore, the XSCF switches from this unusable time zone to Coordinated Universal Time (UTC) and operates in UTC.
    When the set time zone operates in UTC, execute the settimezone -c settz -a command, and check the settable time zones. If the time zone list does not have a set time zone, set a time zone again.
  2. In a system that implements daylight saving time, suppose that the current time in the daylight saving time period is changed by the setdate -s command to a time that is within one hour of the ending of daylight saving time. Then, the set time will be outside of daylight saving time (that is, in winter time).
    In the following example, an attempt is made to set the local time to 1:40 AM October 31 (JDT) during daylight saving time, and daylight saving time ends 2:00 AM October 31. The result is that the time is set to the winter time of 1:47 AM October 31 (JST).
XSCF> showdate
Fri Oct 31 01:20:00 JDT 2014
XSCF> setdate -y -s 103101402014.00
Fri Oct 31 01:40:00 JST 2014
The XSCF will be reset. Continue? [y|n] :y
Thu Oct 30 16:40:00 UTC 2014
Omitted (XSCF automatically rebooted)

XSCF> showdate
Fri Oct 31 01:47:16 JST 2014
  1. To set a time within the period immediately before or after daylight saving time switches, execute the setdate -u command, and set the time in UTC.