Sydney Opera House

Week Three Agenda

• Administrative Issues• Link of the week• Review week two lab assignment• This week’s expected outcomes• Next lab assignment• Break-out problems• Upcoming deadlines• Lab assistance, questions, and answers• Weekly quiz

Administrative Issues

• Lab assignments such as LDAP, Reiser File System, and open source papers shall follow APA documentation style. Franklin University utilizes the following course book in the PF321 class:

Professional FoundationsLearning Strategies

• Grading will focus on capitalization, punctuation, and citation.

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 Caveat:

Knoppix software was designed to be used as a Live CD because of specific features that make it’s performance and stability very suitable. It has been noted in several articles that Knoppix works best from a Live CD. Knoppix enthusiasts have attempted to install this software on a hard disk and encountered problems in the process. These problems are most pronounced when installing updates and new software.

Review week two lab assignmentdrwxrwxrwx permissions (directory)-rwxrwxrwx permissions (file)

The exit statement should always contain a return value.0 indicates normal exit1 indicates failed exit

The return value of a command can be used with conditional or iteration commands.

Review week two lab assignment

Users can connect the standard output of one command into the standard input of another command by using the pipeline operator (|).

Demonstrateps -efps –ef | wc –lps –ef | awk ‘{print $2}’ps –ef | grep dandrearls –l | cut –c1-3who –b (time of last system boot)who –d (print dead processes)who –r (print current run level)

Week two lab assignment

A process associates a number with each file that it has opened. This number is called a file descriptor. When you log in, your first process has the following three open files connected to your terminal.

Standard Input (stdin) : File descriptor 0 is open for reading.

Standard Output (stdout): File descriptor 1 is open for writing.

Standard Error (stderr): File descriptor 2 is open reading.

Demonstratels –a > /tmp/output 2>&1

> is equivalent to 1>< is equivalent to <0

Review week two 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.

Review week two lab assignment

Keyboard

DisplayScreen

Program

#0 stdin

#1 stdout

#2 stderr

File Descriptor

Review week two lab assignment

The grep command searches the named input file(s) forlines containing a given pattern. Each line found is reported to standard output.Demonstrate:

grep UNIX foobar_3grep ‘^UNIX’ foobar_3grep ‘UNIX$’ foobar_3grep pattern foobar_1grep pattern *

The find command lists all pathnames that are in each of the given directories.Demonstrate:

find / -type d –printfind ~dandrear –type d -printfind . –printfind / -name foobar

Review week two 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 < ~dandrear/Winter09_solutions/test.txt

Append the standard output of a command to a file. cat foobar_2 >> foobar_1

Review week two lab assignment

The Advanced Scripting lab assignment requires two shell scripts to be written.

srch.sh srchfile.sh

DemonstrateExecution 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 two lab assignment

Shell syntax srchfile.sh $1 $2original=$PWDcd $originalcd $2listing=`ls –l | cut –c57-80`for file_name in $listingdo

Action Statementsdone

Review week two lab assignmentls –l | morels –l | less (count the fields/use “q” to quit)ls -a (does not hide entries)less 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)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 thesort function and written in ascending order in thetest_file.txt file.

Review week two lab assignment> test_filecat /etc/passwdgrep x /etc/passwd | cut –d’:’ –f1chmod 705 *chmod 705 test_filegrep lines ~dandrear/Winter09_solutions/foobar_1find ~dandrear –type d -print myArray[1]=$1 $0

Review week two lab assignment

Demonstrate/export/home/dandrear/.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 two lab assignmentHOME = is set to the full path name of your login directory

(/export/home/dandrear)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 filesEDITOR = Pathname for your editor

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 PerlPerl - 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

Next lab assignmentPerl’s range of flexibility

- System administration- Web development- Network programming- GUI development

Major features- Procedural Programming

Sequence or unstructured statementsIncludes routines, subroutines, methods, or functions

- Object Oriented ProgrammingModule uses “objects” and their interactions to design applications and computer programs.

Next lab assignment

Major features (continued)

- Powerful built-in support for text

processing

- Large collection of third-party

modules.

Break out problems1. scalar@ARGV2. $ARGV[0]3. exit 04. unless5. $NUMBER6. exit 17. $ARGV[1]8. % (%directory)9. $ ($quote)10. @ (@names)11. diff12. tr “[a-z]” “[A-Z]” < filein > fileout

Next lab assignment

Read the text, Programming Perl

Chapter One (1)

Chapter Two (2)

Chapter 32: Standard Modules

Chapter 33: Diagnostic Output Messages

Upcoming Deadlines

• Lab Assignment 3-1 due on 1/29/09• Lab Assignment 4-1 due on 2/5/09• Lab Assignment 7-1 Mid-term exam 2/19/09 • Mid term outline will be posted on the Bulletin

Board by 2/4/09.

Lab assistance, questions and answers

Questions

Comments

Concerns

After class I will help students with their scripts.