575 lines
7.7 KiB
HTML
575 lines
7.7 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="Introduction to Linux"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Quickstart"
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HREF="chap_02.html"><LINK
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REL="PREVIOUS"
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TITLE="Summary"
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HREF="sect_02_04.html"><LINK
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REL="NEXT"
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TITLE="About files and the file system"
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HREF="chap_03.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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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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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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>Introduction to Linux: </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_02_04.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 2. Quickstart</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_03.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_02_05"
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></A
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>2.5. Exercises</H1
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><P
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>Most of what we learn is by making mistakes and by seeing how things can go wrong. These exercises are made to get you to read some error messages. The order in which you do these exercises is important.</P
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><P
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>Don't forget to use the Bash features on the command line: try to do the exercises typing as few characters as possible!</P
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="sect_02_05_01"
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></A
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>2.5.1. Connecting and disconnecting</H2
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><P
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> <P
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></P
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><UL
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><LI
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><P
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>Determine whether you are working in text or in graphical mode.</P
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><P
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>I am working in text/graphical mode. (cross out what's not applicable)</P
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></LI
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><LI
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><P
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>Log in with the user name and password you made for yourself during the installation.</P
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></LI
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><LI
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><P
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>Log out.</P
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></LI
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><LI
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><P
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>Log in again, using a non-existent user name</P
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><P
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>-> What happens?</P
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></LI
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></UL
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>
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</P
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="sect_02_05_02"
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></A
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>2.5.2. Passwords</H2
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><P
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>Log in again with your user name and password.</P
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><P
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></P
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><UL
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><LI
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><P
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>Change your password into <EM
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>P6p3.aa!</EM
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> and hit the <B
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CLASS="keycap"
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>Enter</B
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> key.</P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>Try again, this time enter a password that is ridiculously easy, like <EM
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>123</EM
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> or <EM
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>aaa</EM
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>.</P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>Try again, this time don't enter a password but just hit the <B
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CLASS="keycap"
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>Enter</B
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> key.</P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>Try the command <B
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CLASS="command"
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>psswd</B
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> instead of <B
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CLASS="command"
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>passwd</B
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></P
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><P
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>-> What happens?</P
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></LI
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></UL
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><DIV
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CLASS="warning"
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><P
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></P
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><TABLE
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CLASS="warning"
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WIDTH="100%"
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BORDER="0"
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><TR
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><TD
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WIDTH="25"
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ALIGN="CENTER"
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VALIGN="TOP"
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><IMG
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SRC="../images/warning.gif"
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HSPACE="5"
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ALT="Warning"></TD
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><TH
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ALIGN="LEFT"
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VALIGN="CENTER"
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><B
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>New password</B
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></TH
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></TR
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><TR
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><TD
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> </TD
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><TD
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ALIGN="LEFT"
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VALIGN="TOP"
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><P
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>Unless you change your password back again to what it was before this exercise, it will be <SPAN
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CLASS="QUOTE"
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>"P6p3.aa!"</SPAN
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>. Change your password after this exercise!</P
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><P
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>Note that some systems might not allow to recycle passwords, i.e. restore the original one within a certain amount of time or a certain amount of password changes, or both.</P
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></TD
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></TR
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></TABLE
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></DIV
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="sect_02_05_03"
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></A
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>2.5.3. Directories</H2
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><P
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>These are some exercises to help you get the feel.</P
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><P
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></P
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><UL
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><LI
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><P
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>Enter the command <B
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CLASS="command"
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>cd <TT
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CLASS="filename"
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>blah</TT
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></B
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></P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>Enter the command <B
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CLASS="command"
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>cd <TT
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CLASS="filename"
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>..</TT
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></B
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></P
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><P
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>Mind the space between "cd" and ".."! Use the <B
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CLASS="command"
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>pwd</B
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> command.</P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>List the directory contents with the <B
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CLASS="command"
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>ls</B
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> command.</P
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><P
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>-> What do you see?</P
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><P
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>-> What do you think these are?</P
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><P
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>-> Check using the <B
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CLASS="command"
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>pwd</B
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> command.</P
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></LI
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><LI
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><P
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>Enter the <B
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CLASS="command"
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>cd</B
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> command.</P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>Repeat step 2 two times.</P
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><P
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>-> What happens?</P
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></LI
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><LI
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><P
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>Display the content of this directory.</P
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></LI
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><LI
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><P
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>Try the command <B
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CLASS="command"
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>cd <TT
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CLASS="filename"
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>root</TT
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></B
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></P
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><P
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>-> What happens?</P
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><P
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>-> To which directories do you have access?</P
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></LI
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><LI
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><P
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>Repeat step 4.</P
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><P
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>Do you know another possibility to get where you are now?</P
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></LI
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></UL
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="sect_02_05_04"
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></A
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>2.5.4. Files</H2
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><P
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></P
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><UL
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><LI
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><P
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>Change directory to <TT
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CLASS="filename"
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>/</TT
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> and then to <TT
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CLASS="filename"
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>etc</TT
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>. Type <B
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CLASS="command"
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>ls</B
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>; if the output is longer than your screen, make the window longer, or try <B
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CLASS="keycap"
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>Shift</B
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>+<B
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CLASS="keycap"
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>PageUp</B
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> and <B
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CLASS="keycap"
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>Shift</B
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>+<B
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CLASS="keycap"
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>PageDown</B
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>.</P
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><P
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>The file <TT
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CLASS="filename"
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>inittab</TT
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> contains the answer to the first question in this list. Try the <B
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CLASS="command"
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>file</B
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> command on it.</P
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><P
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>-> The file type of my <TT
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CLASS="filename"
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>inittab</TT
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> is .....</P
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></LI
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><LI
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><P
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>Use the command <B
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CLASS="command"
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>cat <TT
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CLASS="filename"
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>inittab</TT
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></B
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> and read the file.</P
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><P
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>-> What is the default mode of your computer?</P
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></LI
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><LI
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><P
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>Return to your home directory using the <B
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CLASS="command"
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>cd</B
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> command.</P
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></LI
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><LI
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><P
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>Enter the command <B
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CLASS="command"
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>file <TT
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CLASS="filename"
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>.</TT
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></B
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></P
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><P
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>-> Does this help to find the meaning of <SPAN
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CLASS="QUOTE"
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>"."</SPAN
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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 look at "." using the <B
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CLASS="command"
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>cat</B
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> command?</P
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><P
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></P
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></LI
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><LI
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><P
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>Display help for the <B
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CLASS="command"
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>cat</B
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> program, using the <TT
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CLASS="option"
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>--help</TT
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> option. Use the option for numbering of output lines to count how many users are listed in the file <TT
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CLASS="filename"
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>/etc/passwd</TT
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>.</P
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></LI
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></UL
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="sect_02_05_05"
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></A
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>2.5.5. Getting help</H2
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><P
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></P
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><UL
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><LI
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><P
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>Read <B
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CLASS="command"
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>man <TT
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CLASS="parameter"
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><I
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>intro</I
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></TT
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></B
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></P
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></LI
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><LI
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><P
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>Read <B
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CLASS="command"
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>man <TT
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CLASS="parameter"
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><I
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>ls</I
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></TT
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></B
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></P
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></LI
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><LI
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><P
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>Read <B
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CLASS="command"
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>info <TT
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CLASS="parameter"
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><I
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>passwd</I
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></TT
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></B
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></P
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></LI
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><LI
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><P
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>Enter the <B
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CLASS="command"
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>apropos <TT
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CLASS="option"
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>pwd</TT
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></B
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> command.</P
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></LI
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><LI
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><P
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>Try <B
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CLASS="command"
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>man</B
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> or <B
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CLASS="command"
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>info</B
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> on <B
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CLASS="command"
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>cd</B
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>.</P
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><P
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>-> How would you find out more about <B
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CLASS="command"
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>cd</B
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>? </P
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></LI
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><LI
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><P
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>Read <B
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CLASS="command"
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>ls <TT
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CLASS="option"
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>--help</TT
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></B
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> and try it out.</P
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></LI
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></UL
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></DIV
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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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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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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_02_04.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_03.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_02.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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>About files and the file system</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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