lfs-book/chapter06/sysvinit.xml

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  <!ENTITY % general-entities SYSTEM "../general.ent">
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<sect1 id="ch-system-sysvinit" role="wrap">
  <?dbhtml filename="sysvinit.html"?>

  <sect1info condition="script">
    <productname>sysvinit</productname>
    <productnumber>&sysvinit-version;</productnumber>
    <address>&sysvinit-url;</address>
  </sect1info>

  <title>Sysvinit-&sysvinit-version;</title>

  <indexterm zone="ch-system-sysvinit">
    <primary sortas="a-Sysvinit">Sysvinit</primary>
  </indexterm>

  <sect2 role="package">
    <title/>

    <para>The Sysvinit package contains programs for controlling the startup,
    running, and shutdown of the system.</para>

    <segmentedlist>
      <segtitle>&buildtime;</segtitle>
      <segtitle>&diskspace;</segtitle>

      <seglistitem>
        <seg>&sysvinit-ch6-sbu;</seg>
        <seg>&sysvinit-ch6-du;</seg>
      </seglistitem>
    </segmentedlist>

  </sect2>

  <sect2 role="installation">
    <title>Installation of Sysvinit</title>

    <para>When run-levels are changed (for example, when halting the
    system), <command>init</command> sends termination signals to those
    processes that <command>init</command> itself started and that should
    not be running in the new run-level.  While doing this,
    <command>init</command> outputs messages like <quote>Sending processes
    the TERM signal</quote> which seem to imply that it is sending these
    signals to all currently running processes. To avoid this
    misinterpretation, modify the source so that these messages read like
    <quote>Sending processes configured via /etc/inittab the TERM signal</quote>
    instead:</para>

<screen><userinput remap="pre">sed -i 's@Sending processes@&amp; configured via /etc/inittab@g' src/init.c</userinput></screen>

    <para>Maintained versions of the <command>wall</command>,
    <command>mountpoint</command>, <command>last</command>,
    <command>mesg</command>, and <command>utmpdump</command> programs were
    installed earlier by Util-linux. Suppress the installation of Sysvinit's
    versions of these programs and their man pages:</para>

<screen><userinput remap="make">sed -i -e '/utmpdump/d'   \
       -e '/mountpoint/d' \
       -e '/mesg/d' src/Makefile</userinput></screen>

    <para>Compile the package:</para>

<screen><userinput remap="make">make -C src</userinput></screen>

    <para>This package does not come with a test suite.</para>

    <para>Install the package:</para>

<screen><userinput remap="install">make -C src install</userinput></screen>

  </sect2>

  <sect2 id="contents-sysvinit" role="content">
    <title>Contents of Sysvinit</title>

    <segmentedlist>
      <segtitle>Installed programs</segtitle>

      <seglistitem>
        <seg>bootlogd, fstab-decode, halt, init, killall5,
        lastb (link to last), pidof (link to killall5),
        poweroff (link to halt), reboot (link to halt), runlevel, shutdown,
        sulogin, and telinit (link to init)</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="bootlogd">
        <term><command>bootlogd</command></term>
        <listitem>
          <para>Logs boot messages to a log file</para>
          <indexterm zone="ch-system-sysvinit bootlogd">
            <primary sortas="b-bootlogd">bootlogd</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="fstab-decode">
        <term><command>fstab-decode</command></term>
        <listitem>
          <para>Run a command with fstab-encoded arguments</para>
          <indexterm zone="ch-system-sysvinit fstab-decode">
            <primary sortas="b-fstab-decode">fstab-decode</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="halt">
        <term><command>halt</command></term>
        <listitem>
          <para>Normally invokes <command>shutdown</command> with the
          <parameter>-h</parameter> option, except when already in run-level 0,
          then it tells the kernel to halt the system; it notes in the
          file <filename>/var/log/wtmp</filename> that the system is being
          brought down</para>
          <indexterm zone="ch-system-sysvinit halt">
            <primary sortas="b-halt">halt</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="init">
        <term><command>init</command></term>
        <listitem>
          <para>The first process to be started when the kernel has initialized
          the hardware which takes over the boot process and starts all the
          proceses it is instructed to</para>
          <indexterm zone="ch-system-sysvinit init">
            <primary sortas="b-init">init</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="killall5">
        <term><command>killall5</command></term>
        <listitem>
          <para>Sends a signal to all processes, except the processes in its own
          session so it will not kill the shell running the script that called
          it</para>
          <indexterm zone="ch-system-sysvinit killall5">
            <primary sortas="b-killall5">killall5</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="lastb">
        <term><command>lastb</command></term>
        <listitem>
          <para>Shows the failed login attempts, as logged in
          <filename>/var/log/btmp</filename></para>
          <indexterm zone="ch-system-sysvinit lastb">
            <primary sortas="b-lastb">lastb</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="pidof">
        <term><command>pidof</command></term>
        <listitem>
          <para>Reports the PIDs of the given programs</para>
          <indexterm zone="ch-system-sysvinit pidof">
            <primary sortas="b-pidof">pidof</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="poweroff">
        <term><command>poweroff</command></term>
        <listitem>
          <para>Tells the kernel to halt the system and switch off the computer
          (see <command>halt</command>)</para>
          <indexterm zone="ch-system-sysvinit poweroff">
            <primary sortas="b-poweroff">poweroff</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="reboot">
        <term><command>reboot</command></term>
        <listitem>
          <para>Tells the kernel to reboot the system (see
          <command>halt</command>)</para>
          <indexterm zone="ch-system-sysvinit reboot">
            <primary sortas="b-reboot">reboot</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="runlevel">
        <term><command>runlevel</command></term>
        <listitem>
          <para>Reports the previous and the current run-level, as noted in the
          last run-level record in <filename>/var/run/utmp</filename></para>
          <indexterm zone="ch-system-sysvinit runlevel">
            <primary sortas="b-runlevel">runlevel</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="shutdown">
        <term><command>shutdown</command></term>
        <listitem>
          <para>Brings the system down in a secure way, signaling all processes
          and notifying all logged-in users</para>
          <indexterm zone="ch-system-sysvinit shutdown">
            <primary sortas="b-shutdown">shutdown</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="sulogin">
        <term><command>sulogin</command></term>
        <listitem>
          <para>Allows <systemitem class="username">root</systemitem> to log in;
          it is normally invoked by <command>init</command> when the system goes
          into single user mode</para>
          <indexterm zone="ch-system-sysvinit sulogin">
            <primary sortas="b-sulogin">sulogin</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="telinit">
        <term><command>telinit</command></term>
        <listitem>
          <para>Tells <command>init</command> which run-level to change to</para>
          <indexterm zone="ch-system-sysvinit telinit">
            <primary sortas="b-telinit">telinit</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>