https://aznot.com/index.php?action=history&feed=atom&title=Linux%2FTimeLinux/Time - Revision history2026-05-07T03:46:27ZRevision history for this page on the wikiMediaWiki 1.41.0https://aznot.com/index.php?title=Linux/Time&diff=5770&oldid=prevKenneth: /* Time Zones */2020-11-25T22:55:05Z<p><span dir="auto"><span class="autocomment">Time Zones</span></span></p>
<p><b>New page</b></p><div>== Time Zones ==<br />
<br />
See current timezone setting:<br />
sudo zdump /etc/localtime # /etc/localtime Wed Mar 14 09:46:46 2012 MDT<br />
strings /etc/localtime # MST7MDT,M3.2.0,M11.1.0 (and other garbage)<br />
<br />
Set timezone for all users:<br />
mv /etc/localtime /etc/localtime.original<br />
# cp /usr/share/zoneinfo/America/Boise /etc/localtime<br />
ln -sfn /usr/share/zoneinfo/America/Denver /etc/localtime<br />
ln -sfn /usr/share/zoneinfo/America/Los_Angeles /etc/localtime<br />
<br />
Set time zone for current user:<br />
export TZ=America/Denver<br />
<br />
<br />
In Linux, most timezone information is controlled by GLIBC, which relies on the file /etc/localtime. Different distributions do different things with this file; some have it as a symbolic link to the proper timezone definition file (usually in /usr/share/zoneinfo), but most have it as an actual, explicit file.<br />
<br />
Verifying the Timezone File [http://www.grok.lsu.edu/Article.aspx?articleId=2926]<br />
<br />
zdump is a small program that is part of GLIBC. It dumps the information about a given timezone file. If you want to verify what the Daylight Savings times are for a given year with a given file, you can do something like this:<br />
<br />
$ zdump -v /etc/localtime | grep 2007<br />
<br />
The -v tells zdump to display timezone information for all transitions rather than just the current date.<br />
<br />
date:<br />
date<br />
Sun May 2 15:49:55 MDT 2010<br />
<br />
Time Zone:<br />
ENVIRONMENT<br />
TZ Specifies the timezone, unless overridden by command line parameters.<br />
If neither is specified, the setting from /etc/localtime is used.<br />
<br />
Time zones are kept here:<br />
/usr/share/zoneinfo/<br />
<br />
== NTP ==<br />
<br />
See [[NTP]]<br />
<br />
== File Time ==<br />
<br />
Files have access, modify and change times.<br />
<br />
* access time (atime): time the file was last accessed<br />
* modify time (mtime): file modification times<br />
* change time (ctime): status change times<br />
<br />
<pre><br />
$ stat test/<br />
File: `test/'<br />
Size: 4096 Blocks: 8 IO Block: 4096 directory<br />
Device: 900h/2304d Inode: 20987905 Links: 2<br />
Access: (0700/drwx------) Uid: ( 1068/ kenneth) Gid: ( 1068/ kenneth)<br />
Access: 2010-09-20 11:30:01.000000000 -0600<br />
Modify: 2010-09-20 11:14:45.000000000 -0600<br />
Change: 2010-09-20 11:14:45.000000000 -0600<br />
</pre><br />
<br />
List file times:<br />
$ ls -lt<br />
$ ls -ltr # reverse<br />
<br />
Modifiers:<br />
-t mtime - modification time<br />
-u atime - access time<br />
-c ctime - change time<br />
<br />
== America Time Zones ==<br />
<br />
<pre><br />
# cat /etc/timezone<br />
Etc/UTC<br />
</pre><br />
<br />
<pre><br />
Universal<br />
UTC<br />
Zulu<br />
Etc/UTC<br />
<br />
US/Central<br />
America/Chicago<br />
<br />
US/Eastern<br />
America/New_York<br />
<br />
US/Hawaii<br />
Pacific/Honolulu<br />
<br />
US/Mountain<br />
America/Denver<br />
<br />
US/Pacific<br />
America/Los_Angeles<br />
</pre><br />
<br />
https://en.wikipedia.org/wiki/List_of_tz_database_time_zones<br />
<br />
<pre><br />
# date<br />
Sat 16 Feb 15:46:56 UTC 2019<br />
<br />
# TZ=America/Denver date<br />
Sat 16 Feb 08:47:01 MST 2019<br />
</pre><br />
<br />
== keywords ==<br />
<br />
Linux date time timezone<br />
<br />
[[Category:Linux]]</div>Kenneth