Kbase 11152: How to adjust the timezone for daylight savings on UNIX
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/05/1998 |
|
How to adjust the timezone for daylight savings on UNIX
Edit the file: /etc/TIMEZONE
change the environment variable TZ as follows:
TZ = EST - 5EST
TIMEZONE
NAME
timezone - set default system time zone
SYNOPSIS
/etc/TIMEZONE
DESCRIPTION
This file sets and exports the time zone environment
variable TZ.
This file is used in other files that must know the time
zone.
A simple /etc/TIMEZONE file might look like the following:
# Time Zone
TZ=EST5EDT
export TZ
A simple setting for New Jersey could be:
TZ=EST5EDT
where EST is the abbreviation for the main time zone, 5 is
the difference, in hours, between (UTC) (Universal Time
Code, formerly Greenwich Mean Time) and the main time zone,
and EDT is the abbreviation for the alternate time zone.
A southern hemisphere setting such as the Cook Islands could
be as follows:
TZ="KDT9:30KST10:00;64/5:00,303/20:00"
This setting means that KDT is the abbreviation for the main
time zone, KST is the abbreviation for the alternate time
zone, KST is 9 hours and 30 minutes later than UTC, KDT is
10 hours later than UTC, the starting date of KDT is the
64th day at 5 AM, and the ending date of KDT is the 303rd
day at 8 PM.
This TZ
TZ="EST5:00:00EDT4:00:00;J117/2:00:00,J299/2:00:00"
is exactly the same as the one given above, except the day
of the year when the alternate timezone begins and ends is
based on a different Julian number scheme. The Julian
numbers have the range 1-365, and leap years are not taken
into account. February 28 is day 59 and March 1 is day 60.
It is impossible to explicitly refer to the occasional
February 29.
The system administrator must change the Julian start and
end days annually if the longer form of the TZ variable is
used.
Setting the time during the interval of change from the main
time zone to the alternate time zone or vice versa can
produce unpredictable results.
Changing the system clock while the PROGRESS server is
still running will corrupt the timestamps of the .db and
.bi file. It is NOT supported. The user should go to back
up if this operator error is made. In some cases, using
the force option to get into the database and bypass the
timestamp of the before image file is an option.
Refer to the operating system guide or the online manual
("man timezone") for further information.
Progress Software Technical Support Note # 11152