1. ITEC400 Week One Professor Robert D’Andrea

2. Agenda
Introduction Administrative Announcements Course Expected Outcome This Week’s Topics Next Week’s Lab Assignment Break Out Problems Upcoming Deadlines Lab assistance, questions, and chat time

3. Introduction
Instructor Professor Bob D’Andrea Software Engineer Instructor at Franklin University since 2004 Home phone No Cell No Program Chair of Information Security Professor Laurie Crawford Phone No

4. Administrative Announcements
Instructor commitment Respond daily to student s. Post student midterm and final exam status on the course web page folder immediately after each exam has been received from the Student Learning Center (SLC). Office hours Monday through Friday: 9:00 AM – 6:00 PM Saturday and Sunday: 12:00 PM – 6:00 PM Personalized Adobe Connect session can be scheduled on demand by a student needing individual assistance.

5. Administrative Announcements
Course Web Site Read the Class Communication section? Attendance and/or call me if you are unable to attend class. Otherwise, you will be marked “Not Present” and you will receive an notice from Franklin University. cs.franklin.edu server Everyone will need a login to access the cs.franklin.edu machine. Putty is the prescribed open source interface for this class. You will use putty to access the cs.franklin.edu machine. All student lab assignments will be tested under your /export/home/$USER/itec400/homework directory.

6. Administrative Announcements
Recorded Adobe Connect Sessions
Each week, a Power Point presentation is recorded under the following directory:
Franklin Live file name format
The naming convention used for the weekly Power Point files is listed below.
-rwx---r-x 1 dandrear faculty Sep 7 11:08 Week_One_1_UNIX_ppt.ppt
-rwx---r-x 1 dandrear faculty Sep 7 11:07 Week_One_1_UNIX.pptx
The Power Point presentations be available on Monday mornings for printing and/or review prior to the online session. The recorded presentation could contain a slight variation from the actual class version.

7. Administrative Announcements
format for completed lab assignments a notification when an assignment is completed and ready to be graded. The “Subject” line of your notification should contain the following information and format: <User name> <Section Number> <Lab Assig 1-3> Example: dandrear V1WW Lab Assign format for questions <User name> <Section Number> <Question(s)> Example: dandrear V1WW Question(s) Scripts and text file suffix All scripts and text files shall end with the proper suffix (e.g. ,sh, .pl, .txt and .cgi). Homework assistance Do not solicit help from the Internet for lab assignments. If caught soliciting assistance on the Internet, Franklin University will take action against you.

8. Administrative Announcements
Drop Box All lab assignments must be submitted to the Drop Box. The Drop Box is located under your myFranklin course web page “Course Communication” category. Student drop box documentation link is listed below. al.doc /export/home/<user name>/itec400/homework The homework directory is where your scripts and text files will reside for grading.

9. Administrative Announcements
Turnitin.com Assignments
Public Domain/Open Source lab assignments must be submitted to Turnitin.com.
The Light Directory Access Protocol (LDAP) and Public Domain/Open Source lab assignments must be submitted to Turnitin.com.
If Turnitin.com indicates that the percentage of originality is 45 percent or greater, I will not grade the paper. I will recommend that you seek assistance from the Student Learning Center (SLC).
The Announcement folder for the turnitin.com login information.

10. Administrative Announcements
VMware software
The Knoppix software can also be downloaded from the course web page or from the following link:

11. Course expected outcome
Upon successful completion of this course, students will be able to:
Create non-trivial shell scripts.
Perform appropriate UNIX System Administration tasks.
Compose non-trivial scripts using Perl programming language.
Distinguish the roles of Linux and Open Source software.
Incorporate the make utility appropriately within programs.
Create an open source presentation of your choice.
Create a CGI script

12. UNIX Operating System
UNIX comes in a variety of changing flavors (SUNOS, HP-UX, BSD and Solaris, just to name a few). Each of these UNIX types will have small variations from all of the others. This may seem a bit discouraging at first, but in reality each version of UNIX has more in common with all of the other software versions than differences. For instance, the “ls” command will list the current directory in any UNIX environment. The changes or semantics local to any particular brand of UNIX should be explained in the manual pages that come with that particular version of software.

13. UNIX Operating System
The purpose of this explanation is not to explore the differences between UNIX flavors, but rather to assure you that their base lines are all equivalent.

14. UNIX Operating System
The UNIX operating system comes with many commands that allows the user to interact with their computer. UNIX commands are simply programs that are executed on demand. The usual place for the storage of these commands is the /usr/bin directory. The commands available on a particular machine may vary. There is a set number of standard commands that come with all UNIX systems, but there is no limit to the number of commands that can be made available on a system.

15. UNIX Operating System
UNIX, Linux, and HP-UX are all operating systems. The design of an operating system is to coordinate and apply the various parts of the computer -- the processor, the on-board memory, the disk drives, keyboard, video monitors, and mouse to perform useful tasks. The operating system is the central most software program in the machine. It is the mechanism that connects all the internal and external components with administers, programmers, and system users.

16. UNIX Operating System
The UNIX operating system gives a computer certain recognizable characteristics. However, it would be difficult to distinguish between two different computers, if they were loaded with the same operating system. If you took two identical computers and installed different operating systems on each of them, their differences would be apparent to the observer.

17. UNIX Operating System
UNIX was created in the late 1960s, the initial effort was to provide a multiuser, multitasking system for programmers to use. The philosophy behind this design was to keep it simple, lightweight, contain powerful utilities, and write portable code which accessed a network. The UNIX operating system is made up of three components: The kernel, standard utility programs, and system configuration files.

18. UNIX Operating System
Kernel The kernel is a core computer program component of the UNIX operating system. Basically, the kernel is a software program that is loaded into memory when the machine is turned on. The kernel is a memory resident control program. It controls the allocation of hardware resources from the time the machine is turned on until the system is shutdown. The kernel knows what hardware resources are available (like the processor(s), the on-board memory, the disk drives, network interfaces, etc.), and it has the necessary programs to talk to all the devices connected to it. In summary, the kernel is a fundamental part of a modern computer's operating system.

19. UNIX Operating System
Kernel When a computer program makes requests of the kernel, the request is called a system call. Various kernel designs differ in how they manage system calls and resources. For example, a monolithic kernel executes all the operating system instructions in the same address space in order to improve the performance of the system. A microkernel runs most of the operating system's requests in the background in user space, to make the operating system more modular and, therefore, easier to maintain.

20. UNIX Operating System
General kernel functions performed are: • Managing the machine's memory and allocating it to each process. • Scheduling the work done by the CPU so that the work of each user is carried out as efficiently as is possible. • Accomplishing the transfer of data from one part of the machine to another • Interpreting and executing instructions from the shell • Enforcing file access permissions

21. UNIX Operating System

22. UNIX Operating System
Standard utility programs The standard utility programs include utilities like diff, which compares the content of two files, and other more complex utilities that communicate with the operating system.

23. UNIX Operating System
System configuration files The system configuration files are read by the kernel, and many of the standard utilities to configure the initial settings for some computer programs. Configuration files are used for user applications, server processes, and operating system settings. The files are normally written in ASCII or UTF-8, depending on the operating system. They are often referred to as simple databases. UNIX provides several hundred utility programs, often referred to as commands for managing: •Editing •File maintenance •Printing •Sorting •Programming support •Online information

24. UNIX Operating System
User access to a system Logging into a UNIX-like systems requires two pieces of information: a user name, and a password. After a user name and password have been authenticated and accepted, a UNIX-like system shell is created. The shell’s prompt is displayed at the cursor’s position on your screen. Work is executed and accomplished by entering commands at the command prompt. The shell is the user’s most important program on a UNIX-like system. The shell is the interface between you and the UNIX-like operating system, the man-in-the-middle.

25. UNIX Operating System
User access to a system A shell program is a command interpreter; it takes each command or combination of commands and passes them to the kernel to act on. The kernel is responsible for submitting input requests to hardware devices and returning output information from these devices to the user. This output information can optionally be displayed to a CRT screen and/or written to a media. Normally, there are many shells programs available on a UNIX-like system, each with their own set of unique capabilities.

26. UNIX Operating System
What is a shell? Shell programs are designed to fit a specific concept. They accept input commands, interpret the commands, execute the commands, and then possibly wait for another command. When the shell displays the “prompt” it is prompting the user that it is ready to accept another command.

27. UNIX Operating System
The shells found on the cs.franklin.edu (einstein) machine are: /bin/sh /bin/bash /bin/ksh /bin/tcsh /bin/csh

28. UNIX Operating System
What is a shell? Shell programs are designed to fit a specific concept. They accept a command, interpret the command, execute the command, and then possibly wait for another command. The shell displays the “prompt” to notify the user that it is ready to accept another command.

29. UNIX Operating System
Shell scripts are plain-text files, and should be created using a text editor. A shell script begins with a line at the top of the file that identifies the preferred shell to be executed, as follows: #!/bin/sh #!/bin/bash #!/bin/ksh The first two characters are a special syntax that tells the UNIX-like kernel that this is a script and to use the rest of the line as a pathname to the program that will interpret the script. This line is sometimes referred to as the shebang, hash bang, or pound bang line.

30. UNIX Operating System
On most Unix-like systems, the /bin directory contains the shell scripts and system commands. This subdirectory to the root directory contains the executable scripts, which are ready to run.

31. UNIX Operating System Putty Interface login as: dandrear Access denied
password:
Last login: Sun Sep 6 20:31: from
Red Hat Enterprise Linux Server release 6.0 (Santiago)
************
This server is subject to Franklin University Use Policy. You may review
the Use Policy with the command "UsePolicy".
To be informed of position postings or internship opportunities, subscribe
to the discuss listserv associated with your major (CS, ITEC, MIS, WEBD,
or MSCS). You can do that from
If you run into difficulty, contact Jane Sieberth,
***************
/export/home/dandrear>

32. UNIX Operating System
When you complete the coding of your script, you will want to change the permissions to make it executable. The chmod command should be used as follows:
chmod 705 printnum.sh
chmod 705 maxlines.sh
-rwx---r-x 1 dandrear faculty 986 Jan 4 19:19 printnum.sh

33. UNIX Operating System
After making the script permissions executable, execute your script by typing ./ to tell UNIX-like operating system to run the script in the current directory, rather than search the PATH variable. If you fail to find the script, it can always be executed by running the shell program followed by the script name, as bash printnum.sh

34. UNIX Operating System
The shell program recognizes a limited set of commands, and must be given commands in such a way that can be understood. Each shell command consists of a command name, options, and arguments that are separated by white space. Similarly to writing a sentence where it must contain a subject, a verb, and white space to be a valid. The basic shell command line is: command name [-options] [arguments]

35. UNIX Operating System
The command name is the name of the program you want the shell to execute. The command option usually is prefixed with a hyphen, which allows you to alter the behavior of the command. The argument position is the name of directories, files, or programs that the command needs to access. The shell program is executed by the UNIX kernel. A UNIX program is referred to as a process while the kernel is executing it. The kernel can execute the same shell program or any other program simultaneously for many users on a UNIX-like system, and each executing copy of the program is considered an individual process.

36. UNIX Operating System
Many basic shell commands are small subroutines built into the shell program. Commands that are not built into the shell require the kernel to start another process to execute them. When a non-built-in shell command is executed, the shell requests the kernel to create a new sub-process called a process, to perform the command. The child process lives long enough to execute the command. The shell waits until for the child process completes before it accepts the next command.

37. UNIX Operating System
A shell is an entity that takes input from the user and deals with the computer rather than have the user deal directly with the computer. If the user had to deal directly with the computer they would not get much done as the computer only understands strings of 1's and 0's. While this is a bit of a misrepresentation of what the shell actually does, it provides a rough idea that should cause the reader to be grateful that there is such a thing as a shell to interface with.

38. UNIX Operating System
A good way to visualize a shell program When a person drives a car, they don’t have control of every detail that goes into making the engine run or the electronic system or the braking of the vehicle. All the user (or driver in this example) needs to know is that “D” means drive and that pressing or releasing the accelerator pedal will make the car go faster or slower or stop. The dashboard would also be considered part of the shell, since pertinent information relating to the user's involvement in operating the car is displayed there. Pretty simple, huh.

39. UNIX Operating System
In fact, any part of the car that the user has control of while operating the car would be considered part of the shell. The idea of what a shell is should be clearer now. It is a program that allows the user to use the computer without him or her dealing directly with it. It is in a sense a protective layer that prevents the user and computer from coming into contact with one another.

40. UNIX Operating System
What is parsing? To parse a command line means to look at each part of the command line and be able to extract information into an intelligent format, so that it can be executed by the computer. Since there are variations in how different shells parse a command line, it can be assumed that the shell in question is generic. When a user enters a command line at the prompt, the shell begins by analyzing the command line. The shell will break the command line into small indivisible pieces called tokens.

41. UNIX Operating System What is parsing?
Each token is then analyzed in terms of its relationship with the other tokens. This is similar to the way humans write a sentence. If a noun is present, but no verb, the sentence is deemed incomplete. The shell behaves in much the same way. A shell not only checks for missing bits, it also makes sure that what is there is in the correct order. The shell may have to examine a command line more than once to collect all of the tokens. Each examination is called a pass. The reason for multiple passes is that command lines can be quite complicated, there can be all kinds of substitutions and considerations made before a solid conclusion can be made about the command line data.

42. UNIX Operating System
What is parsing? On each pass the shell will make a required substitution and then collect the available tokens. Since the substitutions can be nested (substitutions containing substitutions), the shell may require several passes to collect all of the tokens. If at this point in the process the shell determines that the grammar of the command line is incorrect, an error is displayed to the user. Otherwise the command is executed. While the actual order in which the tokens are gathered is interesting, it is beyond the scope of this course.

43. UNIX Operating System
What is the role of shell variables? One way a shell lets you customize your working environment is by using shell variables. A shell variable is an item, known by a name, that represents a value of some type. As the term “variable” implies, the value of a shell variable can be changed. There are two types of shell variables. First, there are variables that act as off/on switches. Second, there are variables that store a particular value as a string of characters.

44. UNIX Operating System
Shell Variables USER – contains the username. When a file or directories are accessed, the access permissions are verified against the value found in the USER variable. SHELL holds the path to the current command shell. PWD is the present working directory. This environment variable is maintained by the system. HOSTNAME is the current TCP/IP hostname of the computer.

45. UNIX Operating System
Shell Variables HOST – is an environment variable that contains the name of the host machine that is executing your shell program. When connecting to another remote machine through telnet or ftp, the name of the host is transferred to the remote machine, and displayed on the remote terminal so the administrator can know the names of the systems he or she is logged into.

46. UNIX Operating System
Shell Variables HOME variable points to your home directory. MAIL holds the location of the user’s mail spool. LD-LIBRARY_PATH is a variable to indicate directories in which library files may be found. TERM holds the name of the current terminal type. EDITOR holds the text editor name you use.

47. UNIX Operating System
Shell Variables The PATH variable sets the path for a session, which is a colon-delimited list of directories in which UNIX-like systems search for executable programs when you type a program name. PATH=$HOME/bin:/opt/ant/bin:/opt/Lang/jdk1.3.0/j2s dk1_3_0/bin:/usr/local/bin:/bin:/usr/bin:/opt/mysql/bin: /opt/WWW:/opt/Mail:/opt/Lang/Perl/lib:/usr/local/lib:/u sr/local/ssl/lib:/usr/local/pvm3/include:/usr/ucb:/opt/sf w/bin:$HOME:.

48. UNIX Operating System Executing your environment
The behavior of shell commands are determined by the execution of the environment provided by the shell.
The UNIX shell maintains a complete set of environment variables that provide information about different areas of the operating system. For example, there are variables for the terminal type, current working directory, and default file and directory permissions.
The environment variables are passed to all scripts and programs that are not built in to the shell, but may be accessed or modified, by the program. The convention for specifying environment variables is in upper case letters.

49. UNIX Operating System
To view all environment variables, type printenv To view a particular environment variable. echo $EDITOR The above statement outputs the value of the $EDITOR environment variable echo $TERM The above statement outputs the value of the $TERM environment variable. The TERM variable tells the shell what kind of terminal you are using.

50. UNIX Operating System
When you log into a system, the sequence of events can differ when creating your working environment. The particular sequence of events depends on the flavor of UNIX being implemented and the default shell for your account. The HP-UX operating system subscribes to the following sequence of events at log in: The getty process provides the login: prompt seen on your terminal. The getty process reads the provided username, and invokes the login program.

51. UNIX Operating System
The login program receives the username from the getty process, and prompts the user for their password. The login program consults the /etc/shadow file to verify your password. The login program turns off terminal echo so that the password characters are not displayed on the terminal. After the password has been authenticated, the default shell is invoked by accessing the information in the last field of the /etc/passwd file for that username.

52. UNIX Operating System
When the shell program starts, it reads the configuration files called login scripts to configure the execution environment. On HP-UX, the /etc/profile file contains initialization parameters for ksh and sh, while the /etc/csh.login file is used for csh. After the system login scripts have been read, the shell looks for user- specific login scripts. Once the system login scripts have been read, the shell reads user login scripts. The user login scripts are stored in the user’s home directory, where a user can customize their shell environment. The sh and ksh shells look in the .profile. Ksh reads a file defined in the environment variable ENV. Csh reads a file called .cshrc, and if it is the login shell, the file is named, .login.

53. UNIX Operating System
General approach to foreground and background processes When you log in to a UNIX system, the kernel starts a specific shell for you, and connects your shell to your terminal. When a command is entered and executed from the shell, the shell creates a child process to execute the command, and connects the child process to your terminal. By connecting the child process to your terminal, the shell allows you to communicate by sending input to the child process, and receiving output from it. When the child process finishes, all resources are relinquished (reaped) back to the system, your shell regains access to the terminal, redisplays the shell prompt, and waits for your next command.

54. UNIX Operating System
Processes that require users to be active participants (like processing Excel) must execute in the foreground in order to run. These jobs are termed "interactive," and must periodically update the display monitor, and accept input from the user, and allow access to the terminal interface. There are processes that do not require active participation once they are started. For example, a subroutine that initially accepts input data like a pattern and data file from the main script, uses the pattern to find a match in the data file, and writes matched information to an output file. Non-interactive jobs do not accept input commands, display output data on your terminal, and are disconnected from your terminal, and releasing the terminal for interactive use. This type of process is referred to as a “background” process.

55. UNIX Operating System
It is possible to log out of a system, and leave the background processes executing. The down side of this action is not being able to reconnect a background process to a terminal after logging out. If the background process identification information (PID) is known, the process can be terminated from a terminal. The number of background processes executing at the same time can be many, where a foreground process can only execute one process at a time. The reason is because you only have one terminal for viewing and one keyboard at your terminal.

56. UNIX Operating System

57. UNIX Operating System
Why are we studying about AWK ? Awk is an excellent filter and report writer. Many UNIX-like utilities generate rows and columns of information. AWK is an excellent tool for processing rows and columns, than most conventional programming languages. Awk can be considered to be a pseudo-C interpreter, as it understands the same arithmetic operators as C language. AWK has string manipulation functions, which allow it to search for particular string(s) and modify the output. AWK also has associative arrays, which are incredibly useful, and is a feature most common computing languages lack.

58. UNIX Operating System
Different releases of AWK AWK - the original from AT&T NAWK - A newer, improved version from AT&T GAWK - The Free Software foundation's version I suggest you either use NAWK, or GAWK, or convert your AWK script into PERL using the "a2p" conversion program which comes with Perl.

59. UNIX Operating System
Shell Set Command Debugging part of a script: set -x # activate debugging # your commands go here... set +x # stop debugging

60. UNIX Operating System
Set -A is Korn Shell (ksh) specific (not available in bash or POSIX SH) and it initializes an array with the specified value(s). $ set -A COLORS "red" "green" "blue" $ print ${COLORS[0]} red $ print ${COLORS[1]} green $ print ${COLORS[2]} blue

61. UNIX Operating System
Shell syntax $# - Number of positional parameters (count) $! - Background PID $$ - Process PID $ - Provides the content of a variable ($NUMBER) $0, $1, $2, $3 …$9 - This syntax example represents the positional parameters on the command line. ./printnum.sh 4 $0 = ./printnum.sh $1 = 4 $# = 1

62. UNIX Operating System
Shell syntax examples ./printnum.sh $0 = ./printnum.sh $1 = 3 $2 = 7 $3 = 10 $# = 3 ./maxlines.sh /bin $0 = ./maxlines.sh $1 = /bin $# = 1

63. UNIX Operating System
Shell syntax A variable is a place holder to the script known as a parameter. They are represented by a dollar sign ($) followed by a number from 0-9. The $0 variable represents the name of the script, $1 is the first parameter to the script, $2 is the second parameter, and so on.

64. UNIX Operating System
“ “ - Double quotes. Removes special meaning of all enclosed characters, except $, `, “, and \. Example: print “The price is $Price.\n”; (interpolation) ‘ ’ - Literal quotes. Removes the special meaning of all enclosed characters. A single quote cannot appear within single quotes because a single quote denotes the end of the string.

65. UNIX Operating System
` ` - Single Back-Tic quotes. Used for command substitution. Example: echo The date is `date` (interpolation) LINES=`wc -l $ENTRY | cut -c 1-7` LISTING=`ls -l | cut -f 9` NUMBER=$(($NUMBER - 1))

66. UNIX Operating System
exit 0 – The return values is a number from 0 to 255. A value of zero (0) indicates a normal exit. exit 1 - Indicates a failure occurred. if [ -d "$1" ] then action statement fi #Print the new line counts wc –l - Word count with –l (line option). ~ - Tilde (~ dandrear means /export/home)

67. UNIX Operating System
while [ condition] do action statement(s) done if [ condition ] then fi

68. UNIX Operating System
for name in * do action statements done Example: while [ "$1" != "" ] # Store the value zero (0) in the variable size. $size = 0

69. UNIX Operating System
Example: ./printnum.sh 2 8 $0= ./printnum.sh if [ $# –ne 1 ] then echo “Please enter a command line argument” fi

70. UNIX Operating System
logfile="/var/adm/messages" foreach mon in Sun Mon Tue Wed Thu Fri Sat do grep $mon $logfile > $logfile.$mon done

71. UNIX Operating System
Features of the text editor “vi” Vi was the first full screen text editor written for UNIX. It was initially designed to be simple and small in size. The designers intended vi to fit on a floppy- based emergency boot system. For this specific reason, you may need to use it in an emergency recovery situation. Most Linux distributions ship with a variant of vi known as Vim. Vim has been enhanced to support more features than the original vi editor. You will find that most distributions of Vim support launching it by typing vi, as if it were the original vi.

72. UNIX Operating System
Vi is made up of three modes: (a) command, (b) Ex, and © Insert. The command mode accepts commands, which are usually single characters. For example, o and O and I and an all enter the insert mode, but in different ways. The O and o open a line above and below, respectively where the cursor is positioned. The Ex mode is entered for saving your file. This is initiated by typing a colon (:), followed by entering a w or q character to save or not to retain the information in the file. After executing in the ex-mode, vi automatically returns to the command mode. The Insert mode allows you to enter text that appears on the terminal. To exit the insert mode, depress the Esc key, which will return you to the command mode.

73. UNIX Operating System
Basic vi commands Save text file - :wq! Delete a character - x Inserts a new line immediately below the current line - o Inserts a new line immediately above the current line - O Undo any changes - u Change current word - cw Move around in file using the line number - <number>G Insert information on left side of a character - i Insert information on right side of a character - a Delete a line in a file - dd

74. Hands-on-information
Review Lab Assignment 2-1 Simple Shell scripting. Lab assignments should be recorded on cs.franklin.edu (cs.franklin.edu) machine in your “/export/home/$USER/itec400/homework” directory. Demonstrate how to create a file using the “vi” editor. Execute printnum.sh and maxlines.sh scripts on the cs.franklin.edu machine. Lab Assignment 2-1 will be complemented with script logic. Script logic will be utilized to jump start the lab assignment. It contains script logic, 70% percent of the needed coding, and helpful hints to assist your programming skills. In addition to script logic, you will receive a Shell and Perl Commands Quick Reference document in .

75. Hands-on-information
Set up course directories (case sensitive) /export/home/dandrear mkdir itec400 chmod 705 itec400 cd itec400 mkdir homework chmod 705 homework cd homework

76. Unix Operating System
Moving Around in UNIX ls –a ps –ef whoami rmdir touch less w tail head sort man

77. Break Out Problems
Moving Around in UNIX ps –ef | wc –l who | awk ‘{print $1}’ | sort –u | wc –l ps –ef | awk ‘{print $1}’ |sort –u | wc –l ps –ef | awk ‘{print $9, $1}’ cat ~/dandrear/.profile

78. Break Out Problems
find /bin -name gzip find /etc -name motd > newfile rm file_name date | cut –c cp test_data.txt ~dandrea/temp mv test_data.txt ~dandrear/temp printf $NUMBER touch newfile

79. Upcoming Deadlines
Read Chapters 1, 2, and 3 in your textbook, Essential System Administration. Read Module 1 and 2 listed under the course Web site.

80. UNIX Operating System
Questions? Comments? Concerns? After each Adobe Connect session, I will remain online to provide assistance or answer questions.

81. Lab assistance, questions, and chat time