Chapter 0
A “Quick-Start”
into the UNIX
Operating System
Objectives
• To introduce the UNIX Text User Interface and show the generic
structure of UNIX commands
• To describe how to connect and log on to a computer running
UNIX operating system
• To explain how to manage and maintain files and directories
• To show where to get online help for UNIX commands
• To demonstrate the use of a beginner’s set of utility commands
• To cover the basic commands and operators
alias, biff, cal, cat, cd, cp, exit, hostname, login, lp, lpr, ls, ma,
mesg, mkdir, more, mv, passwd, pg, pwd, rm, rmdir, talk, telnet,
unalias, uname, whatis, whereis, who, whoami, write
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Structure of a UNIX command
$ command [ [ - ] option (s) ]
[ option argument (s) ]
Examples:
• $ ls
• $ ls
-la
• $ ls
-la
• $ lpr
-Pspr
m*
-n
3
proposal.ps
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[ command argument (s) ]
Logging On and Logging Off
• General Categories
– Local Area Network (LAN) Connection.
– Internet Connection.
– Stand-Alone Connection.
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1. Connecting via a UNIX Terminal
login: your_username <Enter>
password: your_password <Enter>
NOTICE: 1. This machine is rebooted at 4:15
am daily.
2. Please keep accounts below 100
MB. (du)
3. Limit TOTAL modem connect
times to ONE hour from the hours
of 5:00 PM to midnight.
You have new mail.
DISPLAY = (upsun17.egr.up.edu:0.0) <Enter>
TERM = (FreeBSD) <Enter>
Upibm7.egr.up.edu:~ 1$
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2. Connecting via PuTTY on a Microsoft Windows
Machine
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3. Connecting via a Telnet Client on a Microsoft
Windows Machine.
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File Maintenance Commands and Help on
UNIX Command Usage
• What is File Maintenance?
• File and Directory Structure
– Home Directory
– Current Working Directory
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File Maintenance Commands and Help on
UNIX Command Usage (Contd)
• Viewing the Contents of Files
– cat, more
$ cat > myfile
This is an example of how to use the cat command to add plain text to a file
<Ctrl-D>
$ more myfile
This is an example of how to use the cat command to add plain text to a file
$
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File Maintenance Commands and Help on
UNIX Command Usage (Contd)
• Creating, Deleting and Managing Files
– cp, mv, rm, ls
$ cp myfile myfile2
$ mv myfile2 renamed_file
$ mv “latest revisions october.txt” laterevs.txt
$ rm renamed_file
$ ls
Desktop
Mail
XF86Config.new
kdeinit.core
order.asp.html
order.asp_files
myfile myfile2
$ ls –al
...
$
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File Maintenance Commands and Help on
UNIX Command Usage (Contd)
• Creating, Deleting and Managing Directories
– mkdir, cd, pwd, rmdir
$ mkdir first
$ cd first
$ pwd
/usr1.b/bobk/first
$ cd
$ pwd
/usr1.b/bobk
$ cp myfile myfile2
$ ls my*
myfile myfile2
$ rmdir first
rmdir: first: Directory not empty
$
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File Maintenance Commands and Help on
UNIX Command Usage
• Obtaining Help with the man Command
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File Maintenance Commands and Help on
UNIX Command Usage (Contd)
• Obtaining Help with the man Command
– man [options][-s section] command-list
$ man ls
LS(1) FreeBSD General Commands Manual LS(1)
NAME
ls - list directory contents
SYNOPSIS
ls [-ABCFGHLPRTWZabcdfghiklmnopqrstuwx1] [file ...]
DESCRIPTION
For each operand that names a file of a type other than directory, ls displays
its name as well as any requested, associated information. For each operand
that names a file of type directory, ls displays the names of files contained
within that directory, as well as any requested, associated information.
If no operands are given, the contents of the current directory are displayed.
If more than one operand is given, nondirectory operands are displayed first;
directory and nondirectory operands are sorted separately and in lexicographical
order.
The following options are available:
Press <SPACE> to continue, or q to quit q
$ man -s2 read
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File Maintenance Commands and Help on
UNIX Command Usage (Contd)
• Other Methods of Obtaining Help
– whatis
$ whatis login set setenv
login(1) -sign on
set(1) -set runtime parameters for session
setenv (1) -change or add an environment variable
$
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Utility Commands
• Examining System Setups
– whereis, whoami
$ whoami
bobk
$ whereis mkdir
mkdir: /usr/bin/mkdir
$
• Printing and General Utility Commands
– lpr, cal
$ lpr -Pspr order.eps
$
• Communication Commands
– write username
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Utility Commands (Contd)
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Command Aliases
• The alias command can be used to create pseudonyms
(nicknames) for commands
• Syntax for the alias command is:
– alias [name [ = string ] …] Bourne, Korn, Bash shells
– alias [name [ string ] ]
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C shell
The alias Command Examples
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