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+                      r82fc053
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 <sect1 id="ch-scripts-udev">
   <?dbhtml filename="udev.html"?>
+<sect1 id="ch-scripts-eudev">
+  <?dbhtml filename="eudev.html"?>
   <title>Device and Module Handling on a CLFS System</title>
   <indexterm zone="ch-scripts-udev">
     <primary sortas="a-systemd">Systemd</primary>
     <secondary>udev usage</secondary>
+  <indexterm zone="ch-scripts-eudev">
+    <primary sortas="a-Eudev">Eudev</primary>
+    <secondary>usage</secondary>
   </indexterm>
   <para>In <xref linkend="chapter-building-system"/>, we installed systemd,
   which contains systemd-udevd, previously known as Udev. Before we go into
   the details regarding how this works, a brief history of previous methods of
   handling devices is in order.</para>
+  <para>In <xref linkend="chapter-building-system"/>, we installed the Eudev
+  package. Before we go into the details regarding how this works,
+  a brief history of previous methods of handling devices is in
+  order.</para>
   <para>Linux systems in general traditionally use a static device creation
 …
   the world.</para>
   <para>Using the Udev method, only those devices which are detected by the
+  <para>Using the Eudev method, only those devices which are detected by the
   kernel get device nodes created for them. Because these device nodes will be
   created each time the system boots, they will be stored on a <systemitem
 …
   <sect2>
     <title>Udev Implementation</title>
+    <title>Eudev Implementation</title>
     <sect3>
 …
     <sect3>
+      <title>Eudev Bootscript</title>
+      <para>The <command>S10udev</command> initscript takes care of creating
+      device nodes when Linux is booted. The script unsets the uevent handler
+      from the default of <command>/sbin/hotplug</command>.  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. Next, the bootscript copies any static
+      device nodes that exist 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.
+      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. The bootscript then starts the Eudev daemon,
+      <command>udevd</command>, which will act on any uevents it receives.
+      Finally, the bootscript forces the kernel to replay uevents for any
+      devices that have already been registered and then waits for
+      <command>udevd</command> to handle them.</para>
+    </sect3>
+    <sect3>
       <title>Device Node Creation</title>
       <para>To obtain the right major and minor number for a device, Udev relies
+      <para>To obtain the right major and minor number for a device, Eudev relies
       on the information provided by <systemitem
       class="filesystem">sysfs</systemitem> in <filename
 …
       <emphasis>0</emphasis>. The names and permissions of the nodes created
       under the <filename class="directory">/dev</filename> directory are
+      determined by rules specified in the files within the
+      <filename class="directory">/lib/udev/rules.d</filename> and <filename
+      class="directory">/etc/udev/rules.d/</filename> directories. These files
+      have names that start with numbers, and are evaluated in numerical order.
+      If <command>udevd</command> can't find a rule for the device it is
+      creating, it will default permissions to <emphasis>660</emphasis> and
+      ownership to <emphasis>root:root</emphasis>. </para>
+      determined by rules specified in the files within the <filename
+      class="directory">/etc/udev/rules.d/</filename> directory. These are
+      numbered in a similar fashion to the CLFS-Bootscripts package. If
+      <command>udevd</command> can't find a rule for the device it is creating,
+      it will default permissions to <emphasis>660</emphasis> and ownership to
+      <emphasis>root:root</emphasis>. Documentation on the syntax of the Eudev
+      rules configuration files is available in
+      <filename>/usr/share/doc/udev/writing_udev_rules/index.html</filename></para>
     </sect3>
 …
       might contain the string
       <quote>pci:v00001319d00000801sv00001319sd00001319bc04sc01i00</quote>.
       The default rules provided by Udev will cause <command>udevd</command>
+      The default rules provided by Eudev will cause <command>udevd</command>
       to call out to <command>/sbin/modprobe</command> with the contents of the
       <envar>MODALIAS</envar> uevent environment variable (that should be the
 …
       <title>A kernel module is not loaded automatically</title>
       <para>Udev will only load a module if it has a bus-specific alias and the
+      <para>Eudev will only load a module if it has a bus-specific alias and the
       bus driver properly exports the necessary aliases to <systemitem
       class="filesystem">sysfs</systemitem>. In other cases, one should
       arrange module loading by other means. With Linux-&linux-version;, Udev is
+      arrange module loading by other means. With Linux-&linux-version;, Eudev is
       known to load properly-written drivers for INPUT, IDE, PCI, USB, SCSI,
       SERIO and FireWire devices.</para>
       <para>To determine if the device driver you require has the necessary
       support for Udev, run <command>modinfo</command> with the module name as
+      support for Eudev, run <command>modinfo</command> with the module name as
       the argument.  Now try locating the device directory under
       <filename class="directory">/sys/bus</filename> and check whether there is
 …
       class="filesystem">sysfs</systemitem>, the driver supports the device and
       can talk to it directly, but doesn't have the alias, it is a bug in the
       driver. Load the driver without the help from Udev and expect the issue
+      driver. Load the driver without the help from Eudev and expect the issue
       to be fixed later.</para>
 …
       busses. Expect this issue to be fixed in later kernel versions.</para>
       <para>Udev is not intended to load <quote>wrapper</quote> drivers such as
+      <para>Eudev is not intended to load <quote>wrapper</quote> drivers such as
       <emphasis>snd-pcm-oss</emphasis> and non-hardware drivers such as
       <emphasis>loop</emphasis> at all.</para>
 …
     <sect3>
       <title>A kernel module is not loaded automatically, and Udev is not
+      <title>A kernel module is not loaded automatically, and Eudev is not
       intended to load it</title>
 …
       enhances the functionality of <emphasis>snd-pcm</emphasis> by making the
       sound cards available to OSS applications), configure
       <command>modprobe</command> to load the wrapper after Udev loads the
       wrapped module. To do this, add an <quote>install</quote> line to a file
       in <filename>/etc/modprobe.d</filename>. For example:</para>
+      <command>modprobe</command> to load the wrapper after Eudev loads the
+      wrapped module. To do this, add an <quote>install</quote> line in
+      <filename>/etc/modprobe.conf</filename>. For example:</para>
 <screen role="nodump"><literal>install snd-pcm /sbin/modprobe -i snd-pcm ; \
     /sbin/modprobe snd-pcm-oss ; true</literal></screen>
+    </sect3>
+    <sect3>
+      <title>Udev loads some unwanted module</title>
+      <para>If the module in question is not a wrapper and is useful by itself,
+      configure the <command>S05modules</command> bootscript to load this
+      module on system boot. To do this, add the module name to the
+      <filename>/etc/sysconfig/modules</filename> file on a separate line.
+      This works for wrapper modules too, but is suboptimal in that case.</para>
+    </sect3>
+    <sect3>
+      <title>Eudev loads some unwanted module</title>
       <para>Either don't build the module, or blacklist it in
       <filename>/etc/modprobe.d</filename> file as done with the
+      <filename>/etc/modprobe.conf</filename> file as done with the
       <emphasis>forte</emphasis> module in the example below:</para>
 …
     <sect3>
       <title>Udev creates a device incorrectly, or makes a wrong symlink</title>
+      <title>Eudev creates a device incorrectly, or makes a wrong symlink</title>
       <para>This usually happens if a rule unexpectedly matches a device. For
 …
     <sect3>
       <title>Udev rule works unreliably</title>
+      <title>Eudev rule works unreliably</title>
       <para>This may be another manifestation of the previous problem. If not,
 …
     <sect3>
       <title>Udev does not create a device</title>
+      <title>Eudev does not create a device</title>
       <para>Further text assumes that the driver is built statically into the
       kernel or already loaded as a module, and that you have already checked
       that Udev doesn't create a misnamed device.</para>
       <para>Udev has no information needed to create a device node if a kernel
+      that Eudev doesn't create a misnamed device.</para>
+      <para>Eudev has no information needed to create a device node if a kernel
       driver does not export its data to <systemitem
       class="filesystem">sysfs</systemitem>.
 …
       <title>Device naming order changes randomly after rebooting</title>
       <para>This is due to the fact that Udev, by design, handles uevents and
+      <para>This is due to the fact that Eudev, by design, handles uevents and
       loads modules in parallel, and thus in an unpredictable order. This will
       never be <quote>fixed</quote>. You should not rely upon the kernel device
       names being stable. Instead, create your own rules that make symlinks with
       stable names based on some stable attributes of the device, such as a
       serial number or the output of various *_id utilities installed by Udev.
+      serial number or the output of various *_id utilities installed by Eudev.
       See <xref linkend="ch-scripts-symlinks"/> and
       <xref linkend="chapter-network"/> for examples.</para>

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