lfs-book-zh_CN/chapter05/installasuser.xml

<sect1 id="ch05-installasuser">
<title>Install all software as an unprivileged user</title>
<?dbhtml filename="installasuser.html" dir="chapter05"?>

<para>When you are logged in as root during Chapter 5, it is possible
that some files of your host system will be overwritten by the ones
you'll build in Chapter 5. There can be all kinds of reasons for this
to happen, for example because the $LFS environment variable is not
set. Overwriting some files from your host system will most likely
cause all kinds of problems, so it's a good idea to be logged in as
an unprivileged user during Chapter 5. To make sure the environment
is as clean as possible, we'll create a new user "lfs" that can be
used while building the static installation. Issuing the following
commands as root will create a new user "lfs":</para>

<para><screen><userinput>useradd -s /bin/bash -m lfs &amp;&amp;
passwd lfs</userinput></screen></para>

<para>Now we need to give proper permissions to the <filename
class="directory">$LFS/static</filename> directory so user "lfs" can write
to it:</para>

<para><screen><userinput>chown -R lfs $LFS/static</userinput></screen></para>

<para>You have to login as user <emphasis>lfs</emphasis> now to continue
with the rest of this chapter. You can do this two ways: either the normal
way through the console or the display manager, or with
<userinput>su - lfs</userinput>. When you're working as user
<emphasis>lfs</emphasis>, type the following commands to set up a good
environment to work in:</para>

<para><screen><userinput>cat &gt; ~lfs/.bash_profile &lt;&lt; "EOF"
umask 022

LFS=/mnt/lfs
LC_ALL=POSIX
CC='gcc -s'
export LFS LC_ALL CC
EOF
source ~/.bash_profile</userinput></screen></para>

<para>This profile makes sure the umask is set to 022 so newly created
files and directories will have the correct permissions. It is advisable
to keep this setting throughout your LFS installation. Also, the $LFS,
$LC_ALL, and $CC environment variables are set. $LFS has been explained
in previous chapters already. $LC_ALL is a variable that is used for
internationalization.</para>

<para>When your host distribution uses a glibc version older than 2.2.4,
having $LC_ALL set to something other than "C" or "POSIX" while working
through Chapter 5 may cause trouble when you exit the chroot environment
of Chapter 6 and try to return to it. By setting this to "POSIX" ("C"
is an alias for "POSIX") we ensure that everything will work as expected
in the chroot environment.</para>

<para>$CC is a variable we set in order to prevent debugging symbols from
being compiled into our static packages. By omitting these symbols during
the linking stage of compilation, we save hard drive space and decrease
our build time.</para>

</sect1>