lfs-book/chapter06/mountproc.xml

<sect1 id="ch06-proc">
<title>Mounting the proc and devpts file systems</title>
<?dbhtml filename="proc.html" dir="chapter06"?>

<para>In order for certain programs to function properly, the proc and devpts
file systems must be available within the chroot environment.
As a file system can be mounted as many times and in as many places
as you like, it's not a problem that the these file systems are already
mounted on your host system -- especially so because they are virtual 
file systems.</para>

<para>The proc file system is mounted under
<filename class="directory">/proc</filename> by running the
following command:</para>

<para><screen><userinput>mount proc /proc -t proc</userinput></screen></para>

<para>The devpts file system is mounted to <filename class="directory">/dev/pts
</filename> by running:</para>

<para><screen><userinput>mount devpts /dev/pts -t devpts</userinput></screen>
</para>

<para>Should this command fail with an error to the effect of:</para>

<blockquote><screen>filesystem devpts not supported by kernel</screen></blockquote>

<para>It means that your host system does not support devpts.  You have two
options at this point. You can either not worry about it, in which case some
of the tests we will run later will fail, or you can use the following command 
from a terminal not in chroot to put your host's pts system into your new 
LFS's filesystem:</para>

<para><screen><userinput>mount --bind /dev/pts $LFS/dev/pts</userinput></screen>
</para>

<para>You might get warning messages from the mount command, such as
these:</para>

<blockquote><screen>warning: can't open /etc/fstab: No such file or directory
not enough memory</screen></blockquote>

<para>Ignore these, they're just due to the fact that the system
isn't installed completely yet and some files are missing. The mount itself
will be successful and that's all we care about at this point.</para>

<para>The last error (not enough memory) doesn't always show up. It depends
on your system configuration (such as the host system's Glibc version that was
used to compile the mount program with).</para>

<para>Remember, if for any reason you stop working on your LFS, and
start again later, it's important to check that these filesystems are still
mounted inside the chroot environment. Otherwise, some programs might
end up compiled incorrectly.</para>

</sect1>