lfs-book/chapter06/creatingdirs.xml

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<sect1 id="ch-system-creatingdirs">
  <?dbhtml filename="creatingdirs.html"?>

  <title>Creating Directories</title>

  <para>It is time to create some structure in the LFS file system. Create a
  standard directory tree by issuing the following commands:</para>

<screen><userinput>mkdir -pv /{bin,boot,etc/opt,home,lib,mnt,opt}
mkdir -pv /{media/{floppy,cdrom},sbin,srv,var}
install -dv -m 0750 /root
install -dv -m 1777 /tmp /var/tmp
mkdir -pv /usr/{,local/}{bin,include,lib,sbin,src}
mkdir -pv /usr/{,local/}share/{doc,info,locale,man}
mkdir -v  /usr/{,local/}share/{misc,terminfo,zoneinfo}
mkdir -pv /usr/{,local/}share/man/man{1..8}
for dir in /usr /usr/local; do
  ln -sv share/{man,doc,info} $dir
done
ln -sv lib /lib64
ln -sv lib /usr/lib64
mkdir -v /var/{lock,log,mail,run,spool}
mkdir -pv /var/{opt,cache,lib/{misc,locate},local}</userinput></screen>

  <para>Directories are, by default, created with permission mode 755, but
  this is not desirable for all directories. In the commands above, two
  changes are made&mdash;one to the home directory of user <systemitem
  class="username">root</systemitem>, and another to the directories for
  temporary files.</para>

  <para>The first mode change ensures that not just anybody can enter
  the <filename class="directory">/root</filename> directory&mdash;the
  same as a normal user would do with his or her home directory. The
  second mode change makes sure that any user can write to the
  <filename class="directory">/tmp</filename> and <filename
  class="directory">/var/tmp</filename> directories, but cannot remove
  another user's files from them. The latter is prohibited by the so-called
  <quote>sticky bit,</quote> the highest bit (1) in the 1777 bit mask.</para>

  <sect2>
    <title>FHS Compliance Note</title>

    <para>The directory tree is based on the Filesystem Hierarchy Standard (FHS)
    (available at <ulink url="http://www.pathname.com/fhs/"/>). In addition to
    the FHS, we create compatibility symlinks for the <filename
    class="directory">man</filename>, <filename
    class="directory">doc</filename>, and <filename
    class="directory">info</filename> directories since many packages still try
    to install their documentation into <filename
    class="directory">/usr/&lt;directory&gt;</filename> or <filename
    class="directory">/usr/local/&lt;directory&gt;</filename> as opposed to
    <filename class="directory">/usr/share/&lt;directory&gt;</filename> or
    <filename class="directory">/usr/local/share/&lt;directory&gt;</filename>.
    The FHS also stipulates the existence of <filename
    class="directory">/usr/local/games</filename> and <filename
    class="directory">/usr/share/games</filename>. The FHS is not precise as to
    the structure of the <filename class="directory">/usr/local/share</filename>
    subdirectory, so we create only the directories that are needed. However,
    feel free to create these directories if you prefer to conform more strictly
    to the FHS.</para>

  </sect2>

</sect1>