lfs-book/chapter03/creatingdirs.xml

<sect1 id="ch04-creatingdirs">
<title>Creating directories</title>

<para>Before we start creating directories, we need to check the base
system's umask setting.  To do this, we run
<userinput>umask</userinput>.  The result should be 022.  If it isn't,
then run the following command to ensure that the directories will be
created with the correct permissions:</para>

<para><screen><userinput>umask 022</userinput></screen></para>

<para>We would advise you to make sure that the umask is set to 022
throughout your LFS installation.</para>

<para>Let's now create the directory tree on the LFS partition based on the FHS
standard, which can be found at <ulink
url="http://www.pathname.com/fhs/">http://www.pathname.com/fhs/</ulink>.
Issuing the following commands will create a default directory layout:</para>
 
<para><screen><userinput>cd $LFS</userinput>
<userinput>mkdir -p bin boot dev/pts etc/opt home lib mnt proc root sbin tmp var opt</userinput>
<userinput>for dirname in $LFS/usr $LFS/usr/local</userinput>
<userinput><literal>&nbsp;&nbsp;&nbsp;do</literal></userinput>
<userinput>&nbsp;&nbsp;&nbsp;mkdir $dirname</userinput>
<userinput>&nbsp;&nbsp;&nbsp;cd $dirname</userinput>
<userinput>&nbsp;&nbsp;&nbsp;mkdir bin etc include lib sbin share src var</userinput>
<userinput>&nbsp;&nbsp;&nbsp;ln -s share/man man</userinput>
<userinput>&nbsp;&nbsp;&nbsp;ln -s share/doc doc</userinput>
<userinput>&nbsp;&nbsp;&nbsp;ln -s share/info info</userinput>
<userinput>&nbsp;&nbsp;&nbsp;cd $dirname/share</userinput>
<userinput>&nbsp;&nbsp;&nbsp;mkdir dict doc info locale man nls misc terminfo zoneinfo</userinput>
<userinput>&nbsp;&nbsp;&nbsp;cd $dirname/share/man</userinput>
<userinput>&nbsp;&nbsp;&nbsp;mkdir man{1,2,3,4,5,6,7,8}</userinput>
<userinput>done</userinput>
<userinput>cd $LFS/var</userinput>
<userinput>mkdir -p lock log mail run spool tmp opt cache lib/misc local</userinput>
<userinput>cd $LFS/opt</userinput>
<userinput>mkdir bin doc include info lib man</userinput>
<userinput>cd $LFS/usr</userinput>
<userinput>ln -s ../var/tmp tmp</userinput></screen></para>

<para>Normally, directories are created with permission mode 755, which isn't
desired for all directories. The first change is a mode 0750 for the 
$LFS/root directory. This is to make sure that not just everybody can 
enter the /root directory (the same a user would do with /home/username 
directories). The second change is a mode 1777 for the tmp 
directories. This way, any user can write data to the /tmp or /var/tmp 
directory but cannot remove another user's files (the latter is caused 
by the so-called "sticky bit" - bit 1 of the 1777 bit mask).</para>

<para><screen><userinput>cd $LFS &amp;&amp;</userinput>
<userinput>chmod 0750 root &amp;&amp;</userinput>
<userinput>chmod 1777 tmp var/tmp</userinput></screen></para>

<para>Now that the directories are created, copy the source files that were
downloaded in chapter 3 to some subdirectory under $LFS/usr/src (you
will need to create the desired directory yourself).</para>

<sect2>
<title>FHS compliance notes</title>

<para>The FHS stipulates that the /usr/local directory should contain the 
bin, games,include, lib, man, sbin, and share subdirectories. You can 
alter your /usr/local directory yourself if you want your system 
to be FHS-compliant.</para>

<para>Also, the standard says that there should exist a /usr/share/games 
directory, which we don't much like for a base system. But feel free to 
make your system FHS-compliant if you wish. The FHS isn't precise as 
to the structure of the /usr/local/share subdirectories, so we took the 
liberty of creating the directories that we felt needed.</para>

</sect2>

</sect1>