lfs-book/chapter06/flex-inst.xml

<sect2>
<title>Installation of Flex</title>

<para>Install Flex by running the following commands:</para>

<para><screen><userinput>./configure --prefix=/usr &amp;&amp;
make &amp;&amp;
make install &amp;&amp;
cd /usr/bin &amp;&amp;
ln -sf flex lex</userinput></screen></para>

<para>Some programs don't know about flex and try to find the lex program
(flex is a (better) alternative for lex). So to please those few
programs out there we'll create a lex script that calls flex and have
it emulate lex.</para>

<para>Create a new file <filename>/usr/bin/lex</filename> by running the
following:</para>

<para><screen><userinput>cat &gt; /usr/bin/lex &lt;&lt; "EOF"</userinput>
#!/bin/sh
# Begin /usr/bin/lex

exec /usr/bin/flex -l "$@"

# End /usr/bin/lex
<userinput>EOF
chmod 755 /usr/bin/lex</userinput></screen></para>

</sect2>