TZCONFIG(8)

NAME
tzconfig - set the local timezone

SYNOPSIS
tzconfig

DESCRIPTION
This manual page explains how you can use the tzconfig utility to set the local timezone. This is necessary to let your system know about the difference between system time and local time (the time in the real world). It is also necessary to make your system behave nicely when your location uses Daylight Savings Time. A valid system time together with the correct local time zone will give you best performance and highest reliablility. It is especially important in a network environment, where even small time differences can make a mirror refetch a whole ftp site, or where time stamps on external file systems are used. tzconfig is called without any parameters from the shell. First it presents the current setting and asks for verification to change it. It then shows a list of about one dozen geographic areas one can roughly recognize as continents. After choosing a geographic area by number, a list of countries and cities in this area will be shown. You can press the Enter key to reprint the list. To choose a timezone, just press enough letters to resolve ambiguities, and the timezone will be installed for you. If you press too few letters, a list of timezones that begin with the letters you entered will be printed and you have to refine your choice (although you can still choose a timezone from the major list). You may press Ctrl-C to interrupt the script at any time. After you made your choice, tzconfig will try to change the timezone for you. See the Internals section below for technical details. You must have root privilegies to actually change anything. Please use tzselect(1) as a user space command to just look at the timezones. It will print the local time in any timezone recognized by the system.

A WORD OF WARNING
What timezone is correct for your system? It depends on the geographical location of the machine. Getting the correct location is important, but the system must also know how your hardware clock is set. Most DOS based PCs set their hardware clock on Local Time, while most UNIX systems set their hardware clock to UCT. The Debian GNU/Linux system gains its knowledge of this setting from the file /etc/default/rcS. This file contains either the line GMT="-u", which indicates that the hardware clock is set to UCT, or it contains the line GMT="", which declares the hardware clock is set to Local Time. If these setting are correct, and the hardware clock is truely set as indicated, then configuring the proper timezone for the machine will cause the proper date and time to be displayed. If these are not set correctly, the the reported time will be quite incorrect. See hwclock(8) for more details on this topic.

Internals
The work done by tzconfig is actually pretty simple. It just updates the link /etc/localtime to point to the correct timezone installed in /usr/share/zoneinfo/. There is nothing wrong with doing this manually. However, using tzconfig you don't have to remember the path to the timezones.

FILES
/etc/localtime /usr/share/zoneinfo

SEE ALSO
hwclock(8) tzselect(1)

AUTHOR
Copyright 1998 Marcus Brinkmann <brinkmd@debian.org> Edits Copyright 1998 Dale Scheetz <dwarf@polaris.net> Please see nroff source for legal notice.