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<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
<!ENTITY % general-entities SYSTEM "../general.ent">
%general-entities;
]>
<sect1 id="ch-preps-addinguser">
<?dbhtml filename="addinguser.html"?>
<title>Adding the LFS User</title>
<para>When logged in as user <systemitem class="username">root</systemitem>,
making a single mistake can damage or destroy a system. Therefore,
the packages in the next two chapters are built as an unprivileged user.
You could use your own user name, but to make it easier to set up a clean
working environment, we will create a new user called <systemitem
class="username">lfs</systemitem> as a member of a new group (also named
<systemitem class="groupname">lfs</systemitem>) and run commands as &lfs-user; during
the installation process. As <systemitem class="username">root</systemitem>,
issue the following commands to add the new user:</para>
<screen><userinput>groupadd lfs
useradd -s /bin/bash -g lfs -m -k /dev/null lfs</userinput></screen>
<variablelist>
<title>This is what the command line options mean:</title>
<varlistentry>
<term><parameter>-s /bin/bash</parameter></term>
<listitem>
<para>This makes <command>bash</command> the default shell for user
<systemitem class="username">lfs</systemitem>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>-g lfs</parameter></term>
<listitem>
<para>This option adds user <systemitem class="username">lfs</systemitem>
to group <systemitem class="groupname">lfs</systemitem>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>-m</parameter></term>
<listitem>
<para>This creates a home directory for <systemitem
class="username">lfs</systemitem>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>-k /dev/null</parameter></term>
<listitem>
<para>This parameter prevents possible copying of files from a skeleton
directory (the default is <filename class="directory">/etc/skel</filename>)
by changing the input location to the special null device.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>lfs</parameter></term>
<listitem>
<para>This is the actual name for the created user.</para>
</listitem>
</varlistentry>
</variablelist>
<para>If you want to log in as &lfs-user; or switch to &lfs-user; from a
non-&root; user (as opposed to switching to user &lfs-user;
when logged in as &root;, which does not require the &lfs-user; user to
have a password), you need to set a password of &lfs-user;. Issue the
following command as the &root; user to set the password:</para>
<screen role="nodump"><userinput>passwd lfs</userinput></screen>
<para>Grant <systemitem class="username">lfs</systemitem> full access to
all the directories under <filename class="directory">$LFS</filename> by making
<systemitem class="username">lfs</systemitem> the owner:</para>
<screen><userinput>chown -v lfs $LFS/{usr{,/*},lib,var,etc,bin,sbin,tools}
case $(uname -m) in
x86_64) chown -v lfs $LFS/lib64 ;;
esac</userinput></screen>
<note><para>In some host systems, the following <command>su</command> command does not complete
properly and suspends the login for the &lfs-user; user to the background.
If the prompt "lfs:~$" does not appear immediately, entering the
<command>fg</command> command will fix the issue.</para></note>
<para>Next, start a shell running as user &lfs-user;. This can be done by
logging in as &lfs-user; on a virtual console, or with the following
substitute/switch user command:</para>
<screen role="nodump"><userinput>su - lfs</userinput></screen>
<para>The <quote><parameter>-</parameter></quote> instructs
<command>su</command> to start a login shell as opposed to a non-login shell.
The difference between these two types of shells is described in detail in
<filename>bash(1)</filename> and <command>info bash</command>.</para>
</sect1>
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