229 lines
3.7 KiB
HTML
229 lines
3.7 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>Exercises</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Bash Guide for Beginners"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="The Bash environment"
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HREF="chap_03.html"><LINK
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REL="PREVIOUS"
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TITLE="Summary"
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HREF="sect_03_07.html"><LINK
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REL="NEXT"
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TITLE="Regular expressions"
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HREF="chap_04.html"></HEAD
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><BODY
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CLASS="sect1"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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VLINK="#840084"
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ALINK="#0000FF"
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SUMMARY="Header navigation table"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Bash Guide for Beginners</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="sect_03_07.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 3. The Bash environment</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="chap_04.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="sect1"
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><H1
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CLASS="sect1"
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><A
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NAME="sect_03_08"
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></A
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>3.8. Exercises</H1
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><P
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>For this exercise, you will need to read the <B
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CLASS="command"
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>useradd</B
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> man pages, because we are going to use the <TT
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CLASS="filename"
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>/etc/skel</TT
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> directory to hold default shell configuration files, which are copied to the home directory of each newly added user.</P
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><P
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>First we will do some general exercises on setting and displaying variables.</P
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><P
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></P
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><OL
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TYPE="1"
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><LI
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><P
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>Create 3 variables, <TT
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CLASS="varname"
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>VAR1</TT
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>, <TT
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CLASS="varname"
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>VAR2</TT
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> and <TT
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CLASS="varname"
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>VAR3</TT
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>; initialize them to hold the values <SPAN
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CLASS="QUOTE"
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>"thirteen"</SPAN
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>, <SPAN
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CLASS="QUOTE"
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>"13"</SPAN
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> and <SPAN
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CLASS="QUOTE"
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>"Happy Birthday"</SPAN
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> respectively.</P
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></LI
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><LI
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><P
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>Display the values of all three variables.</P
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></LI
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><LI
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><P
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>Are these local or global variables?</P
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></LI
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><LI
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><P
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>Remove <TT
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CLASS="varname"
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>VAR3</TT
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>.</P
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></LI
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><LI
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><P
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>Can you see the two remaining variables in a new terminal window?</P
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></LI
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><LI
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><P
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>Edit <TT
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CLASS="filename"
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>/etc/profile</TT
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> so that all users are greeted upon login (test this).</P
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></LI
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><LI
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><P
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>For the <EM
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>root</EM
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> account, set the prompt to something like <SPAN
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CLASS="QUOTE"
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>"Danger!! root is doing stuff in \w"</SPAN
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>, preferably in a bright color such as red or pink or in reverse video mode.</P
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></LI
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><LI
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><P
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>Make sure that newly created users also get a nice personalized prompt which informs them on which system in which directory they are working. Test your changes by adding a new user and logging in as that user.</P
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></LI
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><LI
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><P
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>Write a script in which you assign two integer values to two variables. The script should calculate the surface of a rectangle which has these proportions. It should be aired with comments and generate elegant output.</P
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></LI
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></OL
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><P
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>Don't forget to <B
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CLASS="command"
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>chmod</B
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> your scripts!</P
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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SUMMARY="Footer navigation table"
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CELLSPACING="0"
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="sect_03_07.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="index.html"
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ACCESSKEY="H"
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="chap_04.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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>Summary</TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="chap_03.html"
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ACCESSKEY="U"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>Regular expressions</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |