mirror of
https://git.linuxfromscratch.org/lfs.git
synced 2025-01-19 05:27:39 +00:00
81fd230419
git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@4648 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689
58 lines
2.5 KiB
XML
58 lines
2.5 KiB
XML
<?xml version="1.0" encoding="ISO-8859-1"?>
|
|
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
|
|
<!ENTITY % general-entities SYSTEM "../general.ent">
|
|
%general-entities;
|
|
]>
|
|
<sect1 id="ch-scripts-setclock">
|
|
<title>Configuring the setclock Script</title>
|
|
<?dbhtml filename="setclock.html"?>
|
|
|
|
<indexterm zone="ch-scripts-setclock">
|
|
<primary sortas="d-setclock">setclock</primary>
|
|
<secondary>configuring</secondary></indexterm>
|
|
|
|
<para>The <command>setclock</command> script reads the time from the hardware clock,
|
|
also known as BIOS or the Complementary Metal Oxide Semiconductor
|
|
(CMOS) clock. If the hardware clock is set to UTC, this script will convert the hardware clock's time to
|
|
the local time using the <filename>/etc/localtime</filename> file
|
|
(which tells the <command>hwclock</command> program which timezone the
|
|
user is in). There is no way to
|
|
detect whether or not the hardware clock is set to UTC time, so this
|
|
needs to be manually configured.</para>
|
|
|
|
<para>If you cannot remember whether or not the hardware
|
|
clock is set to UTC time, find out by running
|
|
the <userinput>hwclock --localtime --show</userinput> command. This will tell
|
|
what the current time is according to the hardware clock. If this time
|
|
matches whatever your watch says, then the hardware clock is set to
|
|
local time. If the output from <command>hwclock</command> is not local
|
|
time, chances are it is set to UTC time. Verify this by adding or
|
|
subtracting the proper amount of hours for the timezone to this
|
|
<command>hwclock</command> time. For example, if you live in the MST
|
|
timezone, which is also known as GMT -0700, add seven hours to the local
|
|
time. Then, account for Daylight Savings Time, which requires
|
|
subtracting an hour (or only add six in the first place) during the summer
|
|
months.</para>
|
|
|
|
<para>Change the value of the <envar>UTC</envar> variable below
|
|
to a value of <parameter>0</parameter> (zero) if the hardware clock
|
|
is <emphasis>not</emphasis> set to UTC time.</para>
|
|
|
|
<para>Create a new file <filename>/etc/sysconfig/clock</filename> by running
|
|
the following:</para>
|
|
|
|
<screen><userinput>cat > /etc/sysconfig/clock << "EOF"
|
|
<literal># Begin /etc/sysconfig/clock
|
|
|
|
UTC=1
|
|
|
|
# End /etc/sysconfig/clock</literal>
|
|
EOF</userinput></screen>
|
|
|
|
<para>A good hint explaining how to deal with time on LFS is available
|
|
at <ulink url="&hints-root;time.txt"/>. It explains issues such as
|
|
time zones, UTC, and the <envar>TZ</envar> environment variable.</para>
|
|
|
|
</sect1>
|
|
|