Differences between version 10 and previous revision of UTC.
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| Newer page: | version 10 | Last edited on Saturday, October 4, 2003 12:44:55 am | by AristotlePagaltzis | Revert |
| Older page: | version 1 | Last edited on Thursday, October 2, 2003 1:57:16 pm | by SamJansen | Revert |
@@ -1 +1,22 @@
-Universal
Coordinated Time
+An [Acronym] for __U__niversale __T__emps __C__oordinee, ie
Coordinated Universal
Time.
+
+This is the standard time zone all other time zones are based on. It replaced [GMT] in the early 1970s. [UTC] is measured with atomic clocks. It is kept within .9 seconds of [TAI], but with an integral number of leap seconds added occasionally to reflect the season at and location on the planet. This way [UTC] stays in sync with the rotation of the earth, making sure midnight always occurs at the same time relative to the stars.
+
+To date all corrections have been positive to account for the tidal drag on the earth which slows the planet down.
+
+For more information see http://tycho.usno.navy.mil/systime.html
+
+Compare [GMT], [TAI].
+
+----
+
+[Unix] systems and cousins traditionally store times as [UTC], and only convert it to the local timezone for display using the system's settings. On a typical [Linux] operating system, __/etc/timezone__ contains the time zone (such as __Pacific/Auckland__), and __/etc/localtime__ is a SymLink to a binary file containing information on your standard offset, your daylight savings offset, and how to calculate when daylight savings is in effect. F.ex,
+
+ __/etc $__ ls -l localtime
+ lrwxrwxrwx 1 root root 33 Apr 22 00:19 __localtime__ -> __/usr/share/zoneinfo/Pacific/Auckland__
+
+You can use the tzselect(1) program (as root) to change these settings.
+
+Also, __/etc/default/rcS__ ''(AddToMe: not on [Slackware]; which distro?)'' contains a __UTC__ variable to tell your [Kernel] whether or not your hardware clock is set to [UTC] or to your localtime. Setting __UTC=yes__ and having your hardware clock running in [UTC] is generally a good idea.
+
+For more about setting up your machine's clock, see HowToClock and [NTP].
