Week Three Agenda
• Administrative Issues
• Link of the week
• Review week two lab assignment
• This week’s expected outcomes
• Next lab assignment
• Upcoming deadlines
• Lab assistance, questions, and answers
Administrative Issues
• Lab assignments such as LDAP, Reiser File System,
and open source papers shall follow APA
documentation style.
APA Style
http://www.apastyle.org/learn/
APA Style Writing Workshop
http://www.franklin.edu/student-services/studentlearning-center/academic-support/workshops.html
• Grading will focus on capitalization, punctuation, and
citation.
Administrative Issues
This will be the last request for Proctor
Information. Many students have already
created and submitted their Proctor
Information. The information will be used for
both the mid-term and final exam, unless the
student submits another Proctor Information
request.
Link of the week
http://www.knoppix.net
This is a Knoppix Web site, receive a free and
Open Source Live Linux CD. Knoppix is a
GNU/Linux distribution that boots and runs
completely from CD. It includes Linux software
and desktop environments, with programs like
OpenOffice.org, The Gimp, Apache, PHP,
MySQL and many more open software
programs.
Link of the week
• http://en.wikipedia.org/wiki/Year_2038_problem
Known as the “Unix Millennium bug” – When you use the
date command in Unix, it computes the date as the
number of seconds from January 1, 1970.
Unix stores that information as a “signed 32-bit integer”.
Well, that’s a really big number that will “flip over” and
become negative on Tuesday, January 19 2038. At
around 3am that morning, some Unix systems will think it
is December 13 1901 at around 8:45pm 
Review Week Two Information
What is the next user interface going to be?
The textual (command line) and the visual (graphical user)
interfaces are the two most common modalities used to
support engineers in network and system administration
positions. The command line interface is recognized as the
first generation and the graphical user interface is
considered the second generation. Currently, research is
trying to determine the next best interface. The command
line interface is known as, “under the hood” method of
interacting with the operating system.
Review Week Two Information
CLI Benefits:
Manipulate textual data
Quick customization of data allows engineers the ability
to change data to another form
Excellent for filtering data on systems
Commands are rich, expressive, flexible, and powerful
GUI Benefits:
Reduces data overload
Simple filtering and manipulation of the data
Excellent for displaying trends in data
Review Week Two Information
Users can connect the standard output of one command
into the standard input of another command by using the
pipeline operator (|).
Demonstrate
ps -ef
ps –ef | wc –l
ps –ef | awk ‘{print $2}’
ps –ef | grep varneyg
ls –l | cut –c1-3
who | sort > /tmp/test_file.txt
The output of the who command is piped to the
sort function and written in ascending order in the
/tmp/test_file.txt file. The “who” and “sort” commands
execute in parallel.
Review Week Two Information
Commands
who –b
who –d
who –r
(time of last system boot)
(print dead processes)
(print current run level)
List directory entries using the ls –l | less command
drwxrwxrwx permissions
-rwxrwxrwx permissions
lrwxrwxrwx permissions
-rwxrwxrwx 2 dandrear
brw-rw---- permissions
crw------Permissions
(directory)
(file)
(Symbolic link)
(Hardlink)
(block)
(characterr)
Review week three lab assignment
A file descriptor is generally an index for an entry in a
kernel-resident data structure that contains information on
all open files. Each process on the system has its own file
descriptor table. A user application passes the abstract
key to the kernel through a system call, and the kernel
accesses the file for the application.
A data structure is a specific way of storing and
organizing data in a computer so that it can be accessed
with high efficiently. Data structures can be used as a
single place for storing unrelated information.
Review Week Two Information
Definition data structure
A data structure is a particular way of storing and
organizing data in a computer so that it can be used
efficiently.
Different kinds of data structures are suited to different
kinds of applications, and some are highly specialized
to specific tasks.
Some common data structures:
array, hash table, linked list, queue, and stack
Review week three lab assignment
File Descriptor
Keyboard
#0 stdin
Program
#1 stdout
Display
Screen
#2
stderr
Review week three lab assignment
Redirect the standard output of a command to a file.
date > /tmp/date_saved
Redirect the standard input of a command so that it
reads from a file instead of from your terminal.
cat < ~varneyg/test.file
Append the standard output of a command to a file.
cat file1 >> file2
“Bit Bucket” – echo “stuff” >/dev/null
Review Week Two Information
The grep command searches the named input file(s) for
lines containing a given pattern. Each line found is reported
to standard output.
Demonstrate:
grep UNIX file_3
grep ‘^UNIX’ file_3
grep ‘UNIX$’ file_3
grep pattern file_1
grep pattern *
The find command lists all pathnames that are in each of the
given directories.
Demonstrate:
find / -type d –print
find ~varneyg–type d -print
find . –print
find / -name file_3
Review Week 2 assignment
Logic Scripts:
http://cs.franklin.edu/~varneyg/itec400/LogicScripts
Lab 2-1: printnum_logic.sh & maxlines_log2.sh
Lab 3-1: srchfile_logic.sh & srsh_logic.sh
NOTE: “…” are areas you need to modify (not tied to
# of characters (Xs are indicative of the # of
characters needed – currently only in
maxlines_logic2.sh)
Review week three lab assignment
The Advanced Scripting lab assignment requires two shell
scripts to be written.
srch.sh
srchfile.sh
Demonstrate
Execution of srch.sh and srchfile.sh
Case #1: ./srch.sh <pattern> <file name / directory name>
The srch.sh script will call the srchfile.sh script to perform a
specific task. That specific task is task to search a file for a
pattern and report it to standard output. When the end of file
is reached, control is then returned to the main script,
srch.sh.
Review week three lab assignment
Shell syntax
srchfile.sh $1 $2
original=$PWD
cd $original
cd $2
listing=`ls –1` (-1 is a number)
for file_name in listing
do
Action Statements
done
Review week three lab assignment
ls –l | more
ls -a
(does not hide entries)
man (utilizes the less command for reading online
documentation).
cat > test_file (keyboard input goes into test_file)
cat < test_file (test_file is displayed on terminal)
(< not necessary – can just use cat test_file)
cat foobar_2 >> foobar_1 (append first file to second file)
who | sort > test_file.txt
The output of the who command is piped to the
sort function and written in ascending order in the
test_file.txt file.
Review week three lab assignment
Demonstrate
/export/home/varneyg/.profile
umask 077
Specifies the default permissions for a file
and directory
Demonstrate
The command line arguments are:
$0 $1 $2 $3 …
./arg_list.sh FIRST_ARG SECOND_ARG
Review week three lab assignment
HOME = is set to the full path name of your login directory
(/export/home/varneyg)
PATH = contains the command search path. It is set to a
series of path names separated by colons (:).
SHELL = This entry may be set by the system administrator
to the path name of a shell interpreter other
than the standard bash.
TERM = specifies what terminal you are using.
TMOUT = variable contains the integer attribute. If you set
the value greater than zero, ksh terminates if
you do not enter a command within the
prescribed number of seconds after ksh
issues the PS1 prompt.
MAIL = Name of your Mail files
PWD = Current or Present Working Directory
Review Week Two Information
Types of File and Directory Access:
Access
r
File Meaning
View file contents
Directory Meaning
Search directory contents
w
Alter file contents
Alter directory contents
x
Run executable file
Make your current
directory
-rwx---------rwx---------rwx
Owner 700
Group 070
Other 007
Review Week Two Information
Shell and Programs Access:
To run a shell script, you will need read (r) and execute
(x) access.
To run a binary executable program, you will need
execute (x) access.
Review week three lab assignment
> test_file
cat /etc/passwd
grep x /etc/passwd | cut –d’:’ –f1
chmod 705 *
chmod 705 test_file
grep lines ~varneyg/testlines
find ~varneyg –type d -print
$0
Week’s 2 & 3 expected outcomes
Upon successful completion of this module,
the student will be able to:
• Create scripts using shell/Perl variables
and program control flow.
• Use redirection and pipes to combine
scripts and executables.
• Use man page system and find script
tools.
• Discuss Perl Language
Next lab assignment
Introduction to Perl
Perl - Practical Extraction and Report Language
• Perl is a simple language
- Compiles and executes like a shell
script or a batch file
- Perl doesn’t impose special growth
limitations on arrays and data strings
- Perl is a composite of C, AWK, and
Basic
- Originally developed to manipulate
text and automating tasks
Next lab assignment
Perl’s range of flexibility
- System administration
- Web development
- Network programming
- GUI development
Major features
- Procedural Programming
Sequence or unstructured statements
Includes routines, subroutines,
methods, or functions
- Object Oriented Programming
Module uses “objects” and their
interactions to design applications and
computer programs.
Next Perl Lab Assignment
• Major features (continued)
- Powerful built-in support for text
processing
- Large collection of third-party
modules. http://www.cpan.org
- Can even download and run on Windows:
http://www.perl.com
Next lab assignment
Read the text, Programming Perl
Chapter One (1)
Chapter Two (2)
Chapter 32: Standard Modules
Chapter 33: Diagnostic Output Messages
Next Perl Lab Assignment
Online Reading Sections
• Chapter One: (under Overview – Natural and Artificial
Languages)
Variable Syntax
Singularities
Pluralities
Arrays, Hashes, Complexities
• Chapter Two: (Under The Gory Details – Bits and Pieces)
Variables, Names, Name Lookups, Scalar Values
Numeric Literals
Pick Your Own Quotes or Leave The Quotes Out Entirely
Interpolating Array Values
Next Perl Lab Assignment
Online Reading Sections
• Chapter Three: (under “The Gory Details – Unary & Binary
Operators)
Multiplicative Operators, Additive Operators
Shift Operators
Named Unary and File Test Operators
Relational Operators, Equality Operators
Bitwise Operators
Upcoming Deadlines
•
•
•
•
•
Obtain Proctor (1-1) due on Jan. 30.
Lab Assignment 2-1 due on Jan. 22.
Lab Assignment 3-1 due on Jan. 29.
Lab Assignment 4-1 due on Feb. 5.
Read Chapters 1 and 2 in Programming Perl text.
Review Chapter 32: Standard Modules
Review Chapter 33: Diagnostic Output
Messages
• Read Module Two listed under the course Web site.
Lab assistance, questions and answers
Questions
Comments
Concerns
After class I will help students with their scripts.