1. CS306
Lab Workout 2
Fall 2017

2. Linux commands workout
Find out your IP address: ifconfig
Test if your Internet is working: ping
Introduce vi as the command line editor
Show how to write data (in ‘i’ mode)
Save as a file (:w)
Exit vi (:q)
Save and exit (:wq)
Exit without saving (:w!)

3. Linux commands workout
Sort contents of a text file using the sort command
more big-text_file.txt
Display the file called big-text_file.txt one page at a time, proceed to next page using the spacebar
head big-text_file.txt
Display the first 10 lines of the file called big-text_file.txt
head -20 big-text_file.txt
Display the first 20 lines of the file called big-text_file.txt
tail big-text_file.txt
Display the last 10 lines of the file called big-text_file.txt
tail -20 big-text_file.txt
Display the last 20 lines of the file called big-text_file.txt

4. Process Life Cycle Diagram

5. Linux commands workout
df –h
du -h
Create a directory structure ./test/child/tmp: mkdir –p ./test/child/tmp
Change to ./test
First create a file called “junk” in the CWD (touch ./junk). Then, create a hard link to it called junk-hardlink using:
ln ./junk junk-hardlink
ln -s ../junk junk-alias
Create a hard link to the directory ../test: ln ../test test-link
Create a soft link to the directory ../test: ln –s ../test test-softlink
Use stat to display the inode structure and link count for
test directory
File test-link
File junk
File junk-hardlink
File junk-alias

6. Linux commands workout
top ps
ps –e
ps –ex
kill -9
background process using & and then fg
pipe operator: ls –l|wc|sort –r
printenv

7. Linux Special Characters Expansions
echo D*
echo ~
echo $((2 + 2))
mkdir { }-0{1..9} { }-{10..12}
ls -l $(which cp)
find /bin -name “*gc*”
grep "this" index.html
grep -c "this" index.html

8. Linux Special Variables
Description $0
The filename of the current script. $n
These variables correspond to the arguments with which a script was invoked. Here n is a positive decimal number corresponding to the position of an argument (the first argument is $1, the second argument is $2, and so on). $#
The number of arguments supplied to a script. $*
All the arguments are double quoted. If a script receives two arguments, $* is equivalent to $1 $2.
All the arguments are individually double quoted. If a script receives two arguments, is equivalent to $1 $2. $?
The exit status of the last command executed. $$
The process number of the current shell. For shell scripts, this is the process ID under which they are executing. $!
The process number of the last background command.

9. Linux Special Variables
Create a text file using: vi test.sh
Press “i” key on keyboard to enter “insert” mode [This allows you to type]
Enter the following lines:
#!/bin/sh
echo "File Name: $0"
echo "First Parameter : $1"
echo "Second Parameter : $2"
echo "Quoted Values:
echo "Quoted Values: $*"
echo "Total Number of Parameters : $#“
Press Esc, followed by wq and Enter – This saves and exits vi
chmod 755 test.sh
Execute ./test.sh this is a “test program”