Trunk is now identical to Testing

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@4648 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

1 files changed, 35 insertions, 0 deletions

diff --git a/chapter07/setclock.xml b/chapter07/setclock.xml
index d933eb59f..0527fac00 100644
--- a/chapter07/setclock.xml
+++ b/chapter07/setclock.xml
@@ -7,6 +7,36 @@
 <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>
@@ -19,4 +49,9 @@ 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>
+