lfs-book-zh_CN/appendixa/flex-desc.xml

<sect2><title>&nbsp;</title><para>&nbsp;</para></sect2>

<sect2><title>Descriptions</title>

<para>(Last checked against version &flex-contversion;.)</para>

<sect3><title>Program file descriptions</title>

<sect4><title>flex</title>
<para>flex is a tool for generating programs which recognize 
patterns in text. Pattern recognition is very useful in many applications. 
A user sets up rules about what to look for and flex will make a program
that looks for those patterns. The reason people use flex is that it is
much easier to set up rules for what to look for than to write the actual
program which finds the text.</para></sect4>

<sect4><title>flex++</title>
<para>flex++ invokes a version of flex which is used exclusively for 
C++ scanners.</para></sect4>

<sect4><title>lex</title>
<para>We create a bash script called lex which calls flex using the -l option.
This is for compatibility purposes for programs which use lex instead
of flex.</para></sect4>

</sect3>

<sect3><title>Library file descriptions</title>

<sect4><title>libfl</title>
<para>libfl is the flex library.</para></sect4>

</sect3>

</sect2>