Changeset 976040f for chapter07/usage.xml

Timestamp:

04/23/2014 08:53:49 PM (10 years ago)

Author:

Bruce Dubbs <bdubbs@…>

Branches:

10.0, 10.0-rc1, 10.1, 10.1-rc1, 11.0, 11.0-rc1, 11.0-rc2, 11.0-rc3, 11.1, 11.1-rc1, 11.2, 11.2-rc1, 11.3, 11.3-rc1, 12.0, 12.0-rc1, 12.1, 12.1-rc1, 7.6, 7.7, 7.8, 7.9, 8.0, 8.1, 8.2, 8.3, 8.4, 9.0, 9.1, arm, bdubbs/gcc13, ml-11.0, multilib, renodr/libudev-from-systemd, s6-init, trunk, xry111/arm64, xry111/arm64-12.0, xry111/clfs-ng, xry111/lfs-next, xry111/loongarch, xry111/loongarch-12.0, xry111/loongarch-12.1, xry111/mips64el, xry111/pip3, xry111/rust-wip-20221008, xry111/update-glibc

Children:

61d3147

Parents:

e040ad1

Message:

Update to man-pages-3.65.
Text changes in Chapter 7.

git-svn-id: ​http://svn.linuxfromscratch.org/LFS/trunk/BOOK@10549 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

File:

• chapter07/usage.xml (modified) (2 diffs)

chapter07/usage.xml

@@ -208 +208 @@
   </sect2>
 
+  <sect2>
+    <title>Udev Bootscripts</title>
+
+      <para>The first LFS bootscript,
+      <filename>/etc/init.d/mountvirtfs</filename> will copy any devices
+      located in <filename class="directory">/lib/udev/devices</filename> to
+      <filename class="directory">/dev</filename>. This is necessary because
+      some devices, directories, and symlinks are needed before the dynamic
+      device handling processes are available during the early stages of
+      booting a system, or are required by <command>udevd</command> itself.
+      Creating static device nodes in <filename
+      class="directory">/lib/udev/devices</filename> also provides an easy
+      workaround for devices that are not supported by the dynamic device
+      handling infrastructure.</para>
+
+      <para>The <filename>/etc/rc.d/init.d/udev</filename> initscript starts
+      <command>udevd</command>, triggers any "coldplug" devices that have
+      already been created by the kernel and waits for any rules to complete.
+      The script also unsets the uevent handler from the default of
+      <filename>/sbin/hotplug </filename>.  This is done because the kernel no
+      longer needs to call out to an external binary.  Instead
+      <command>udevd</command> will listen on a netlink socket for uevents that
+      the kernel raises.</para>
+
+      <para>The <command>/etc/rc.d/init.d/udev_retry</command> initscript takes
+      care of re-triggering events for subsystems whose rules may rely on
+      filesystems that are not mounted until the <command>mountfs</command>
+      script is run (in particular, <filename class="directory">/usr</filename>
+      and <filename class="directory">/var</filename> may cause this).  This
+      script runs after the <command>mountfs</command> script, so those rules
+      (if re-triggered) should succeed the second time around.  It is
+      configured from the <filename>/etc/sysconfig/udev_retry</filename> file;
+      any words in this file other than comments are considered subsystem names
+      to trigger at retry time.  To find the subsystem of a device, use
+      <command>udevadm info --attribute-walk &lt;device&gt;</command> where
+      &lt;device&gt; is an absolute path in /dev or /sys such as /dev/sr0 or
+      /sys/class/rtc.</para>
+
+    <sect3>
+      <title>Module Loading</title>
+
+      <para>Device drivers compiled as modules may have aliases built into them.
+      Aliases are visible in the output of the <command>modinfo</command>
+      program and are usually related to the bus-specific identifiers of devices
+      supported by a module. For example, the <emphasis>snd-fm801</emphasis>
+      driver supports PCI devices with vendor ID 0x1319 and device ID 0x0801,
+      and has an alias of <quote>pci:v00001319d00000801sv*sd*bc04sc01i*</quote>.
+      For most devices, the bus driver exports the alias of the driver that
+      would handle the device via <systemitem
+      class="filesystem">sysfs</systemitem>. E.g., the
+      <filename>/sys/bus/pci/devices/0000:00:0d.0/modalias</filename> file
+      might contain the string
+      <quote>pci:v00001319d00000801sv00001319sd00001319bc04sc01i00</quote>.
+      The default rules provided with Udev will cause <command>udevd</command>
+      to call out to <command>/sbin/modprobe</command> with the contents of the
+      <envar>MODALIAS</envar> uevent environment variable (which should be the
+      same as the contents of the <filename>modalias</filename> file in sysfs),
+      thus loading all modules whose aliases match this string after wildcard
+      expansion.</para>
+
+      <para>In this example, this means that, in addition to
+      <emphasis>snd-fm801</emphasis>, the obsolete (and unwanted)
+      <emphasis>forte</emphasis> driver will be loaded if it is
+      available. See below for ways in which the loading of unwanted drivers can
+      be prevented.</para>
+
+      <para>The kernel itself is also able to load modules for network
+      protocols, filesystems and NLS support on demand.</para>
+
+    </sect3>
+
+    <sect3>
+      <title>Handling Hotpluggable/Dynamic Devices</title>
+
+      <para>When you plug in a device, such as a Universal Serial Bus (USB) MP3
+      player, the kernel recognizes that the device is now connected and
+      generates a uevent. This uevent is then handled by
+      <command>udevd</command> as described above.</para>
+
+    </sect3>
+  </sect2>
+
   <sect2 id="ch-scripts-clock">
     <title>Configuring the System Clock</title>
 
-    <sect3 id="ch-scripts-setclock">
-    <title>System V Clock Configuration</title>
-
-    <indexterm zone="ch-scripts-setclock">
-      <primary sortas="d-setclock">setclock</primary>
+    <indexterm zone="ch-scripts-clock">
+      <primary sortas="d-scripts-setclock">setclock</primary>
     <secondary>configuring</secondary></indexterm>
 
@@ -269 +348 @@
     in the <filename>/etc/sysconfig/rc.site</filename> file.</para></note>
 
-     </sect3>
   </sect2>