Linux Lab Manual

LINUX LAB (15CS47P) 2015 CURRICULLUM
LINUX LAB MANUAL

COURSE CODE: 15CS47P
FOR 4th Sem CS & E

(2017-18)
By
Mrs. RENU HARSHA
HEAD OF THE DEPARTMENT (HOD)
COMPUTER SCIENCE & ENGINEERING
RJS POLYTECHNIC
BANGALORE-34.
For Any Feedback Contact

Email: Velumani2296@gmail.com
RJS POLYTECHNIC, BANGALORE-34. Page 1

List of Graded Practical Exercises

PART-A
1. Introduction- Linux Architecture- Shell, Kernel, System calls. Linux installation-

Steps for installing Linux Operating System
Comparison between Linux and other Operating Systems, Applications of Linux
Operating System.
2. Internal & External commands in Linux. ∑ Internal commands- echo, type, etc.
∑ External commands- ls, cp, mv, rm, cat, etc
∑ Other commands – tput clear, who, cal, date, bc, man, passwd, uname ( with
different options).
3. Working with files & directories.

∑ Know the categories of files.
∑ Directory related Commands – pwd, mkdir, rmdir, cd, ls
∑ Manipulating Absolute paths and Relative paths using cd command.
∑ File related Commands – cat, cp, mv, rm, comm, cmp, diff, tar, umask, wc
4. Basic File attributes.

∑ Listing seven attributes of a file : ls and its options
∑ File Permissions: Absolute and Relative permissions
∑ Manipulating File permissions using chmod command
∑ Manipulating File Ownership using chown command

∑ Manipulating Hardlink and Softlink using ln command
5. Learn to use vi editor.

∑ Three modes of vi editor.
∑ Input mode commands.
∑ Command mode commands.

∑ Ex mode commands.
6. Simple Filters – head, tail, cut, paste, sort, uniq, tr, pr.
7. Expressions & search patterns .(dot operator), *, ^, +, ?, grep, egrep, fgrep 8.

Process Management commands.
∑ Process creation, status, Identifying process, ps -f & its options,
∑ Running process in background, Job control, and Process termination.
∑ Changing process priority, scheduling process (Usage of sleep and wait

commands)
9. Introduction to shell programming.

∑ Introduction, Uses of shell script, Shell special characters, comments,
command separator, escaping, quoting command substitution.
∑ Creating shell script, Shell identifiers, Shell variables, Destroying a variable,
Positional parameters & command line arguments.
∑ Evaluating expressions, Text formatting with echo & tput script termination.
10. Shell control structures

∑ if, case, for, while, relational and logical operators, ∑
Advanced filter – sed and awk.
11. Linux system administration

Managing file system, Disk management utilities, mounts,
umount, df, du, fdisk, su, useradd etc.
12. Linux Environment

Introduction, Environment variables, Command prompt system variables,
Profiles, files, terminal variable stty command and its options, Command
history, editing Environment variable.

PART – B
13. Write a shell script to display current date, time, username and directory.
14. Write script to determine whether given file exist or not, file name is supplied as
command line argument, also check for sufficient number of command line argument
15. Write shell script to show various system configuration like:
a) Currently logged user name and his long name
b) Current shell
c) Your home directory
a) Your operating system type
b) Your current path setting
c) Your current working directory

d) Show all available shells
17. Write a Shell script to accept any two file names and check their file permissions.
18. Write a Shell script to read a file name and change the existing file permissions.
19. Write a shell script to print current month calendar and to replace the current day
number by ‘*’or ‘**’ respectively.

20. Write a C-program to fork a child process and execute the given Linux commands.
21. Write a C-program to fork a child process, print owner process ID and its parent
process ID.
22. Write a C-program to prompt the user for the name of the environment variable, check
its validity and print an appropriate message.

PART- A
COMMANDS

Internal & External commands in Linux

Internal commands
1)Echo
Command:echo
Syntax:echo “arguments”
Purpose:Displays the given text on screen
EX:echo “welcome to linux lab”
OUTPUT:
[sudha@rjsplinux ~]$ echo “welcome to linux lab”
Welcome to linux lab”
[sudha@rjsplinux ~]$
2)Type
Command:type
Syntax:type arguments/command
Purpose:It is used to know the location of the executable program
Ex:type echo
OUTPUT:
[sudha@rjsplinux ~]$ type echo
Echo is shell builtin
[sudha@rjsplinux ~]$ type who
Who is /usr/bin/who
External commands
1)LS
Command:ls
Syntax:ls
Purpose: This command displays all the files and directories.
EX:ls
OUTPUT:
[sudha@rjsplinux ~]$ ls
372CS14041.sh dad sudha parrot sudu1.sh sundisplaymenu.sh
manjupathname.sh sudha.g 3star dot logname.sh pgm1.sh
sun.pineapple end mango pgm7.sh sun11 gowriganapathi
Options of LS
1)-x
Command:-X
Syntax:ls –x
Purpose:It displays in multi columnar output.
2)-f
Command:-f
Syntax:ls –f
Purpose:List the files in long format.
3)-a
Command:-a
Syntax:ls –a
Purpose:List all entries including hidden files.
4)-p
Command:-p
Syntax:ls –p
Purpose:puts a slash after each directory
5)-r
Command:-r
Syntax:ls –r
Purpose:sorts filename in reverse order.
6)-u
Command:-u
Syntax:ls –u
Purpose:sorts the filename by last access time.
7)-l
Command:-l
Syntax:ls –l
Purpose: Displays one filename in each line.
2)CP (Copying a file)

COMMAND:CP
PURPOSE:This command copies a file (or) a group of files.It creates an exact of a
file on disk with different name.
SYNTAX:cp source_file_name destination_file_name
EX:cp xyz abc
OUTPUT:
[velumani@rjsplinux ~]$ cat > xyz
wp
mc
gc
^Z
[1]+ Stopped cat > xyz
[velumani@rjsplinux ~]$ cat abc
cat: abc: No such file or directory
[velumani@rjsplinux ~]$ cp xyz abc
wp
mc
gc
CP OPTIONS
a)Interactive coping(-i):
COMMAND:This option warns the user before overwriting the text file.
SYNTAX:cp –i filename1 filename2
EX:cp –i abc xyz
OUTPUT:
[velumani@rjsplinux ~]$ cp -i fourth fifth
cp: overwrite `fifth'? n
b)Coping directory(-r)
COMMAND:cp –r
SYNTAX:cp –r dirname
PURPOSE:This option copies an entire directory string that is it copies all sub-
directories (or) files.
2)more(paging output):
Command:more
Purpose:This command is used to display a file or program output one
File at a time.
Syntax1:more filename
Syntax2:more filename1 filename2 filename3
Output:
[sudha@rjsplinux ~]$ more xyz
a
b
c
d
3)MV(move command)
Command:mv
Syntax:mv oldfilename newfilename.
Purpose:This command is used to rename the file.
OUTPUT:
[sudha@rjsplinux ~]$ cat > CSE
OS
DBMS
C++
SE
^Z
[1]+ stopped cat > CSE
sudha@rjsplinux ~]$ cat sudha
welcome
gowri
ganapathi
sudha
[sudha@rjsplinux ~]$ mv sudha CSE
[sudha@rjsplinux ~]$ cat CSE
welcome
gowri
ganapathi
sudha
4)RM(remove/delete)
Command:rm
Syntax:rm filename
Purpose:Files can be deleted or removed by using rm command.
OUTPUT:
[velumani@rjsplinux ~]$ cat fourth
OS
DS
PE
[velumani@rjsplinux ~]$ rm fourth
cat: fourth: No such file or directory
5)Cat
Command:cat
Syntax:cat > filename
Purpose:This command is to create, display, concatenate, append information to
files
OUTPUT:
[sudha@rjsplinux ~]$ cat > fourth
OS
DS
^Z
[1]+ stopped cat > fourth
[sudha@rjsplinux ~]$ ls
372CS14041.sh dad fourth parrot sudu1.sh sun
displaymenu.sh manju pathname.sh sudha.g 3star dot
logname.sh pgm1.sh sun. pineapple end mango
pgm7.sh sun11 gowriganapathilinuxfile
To display the contents of the file

Command:cat
Syntax:cat filename
Purpose:This command is to display the contents of an existing file
EX: cat fourth
OUTPUT:
[sudha@rjsplinux ~]$ cat fourth
OS
DS
To copy the contents of second file
Command:cat
Syntax:cat filename1 filename2
Purpose:This command is to store the contents of second file in first file
EX: cat fourth fifth
OUTPUT:
[velumani@rjsplinux ~]$ cat > fourth
OS
DS
^Z
[2]+ Stopped cat > fourth
[velumani@rjsplinux ~]$ cat > fifth
Webprogramm
mobilecomputing
^Z
[3]+ Stopped cat > fifth
[velumani@rjsplinux ~]$ cat fourth fifth
OS
DS
Webprogram
Mobilecomputing
To append data to an existing file

Command:cat
Syntax:cat >> filename
Purpose:This command is used to append data to an existing file.
EX: cat >> fourth
OUTPUT:
[velumani@rjsplinux ~]$ cat >> fourth
PE
^Z
[4]+ Stopped cat >> fourth
OS
DS
PE
Cat options
a) Command: \v
Purpose: Displaying non printable characters. If we have non printing ASCII
character in our input this option is used.
b) Command:- n
Purpose:This option numbers line. Each line of the file will be numbered
Syntax: cat -n filename
EX:cat -n fourth
OUTPUT:
[velumani@rjsplinux ~]$ cat -n fourth

1 OS
2 DS
3 PE
Other commands
1)tput clear
Command:tput clear
Syntax:tput clear
Purpose:This command clears the screen.
EX: tput clear
2)Who
Command:who
Syntax:who
Purpose:This command maintains an account of all users who are logged on
to
the system.It displays the information listing of the users.
OUTPUT:
[velumani@rjsplinux ~]$ who
shashank pts/0 2002-01-01 05:35 (192.168.1.3)
syed pts/2 2002-01-01 05:36 (192.168.1.26)
velumani pts/1 2002-01-01 05:39 (192.168.1.1)
smitha pts/3 2002-01-01 05:40 (192.168.1.6)
vikramkumar pts/4 2002-01-01 05:42 (192.168.1.56)
shwetha pts/6 2002-01-01 05:47 (192.168.1.5)
velumani pts/5 2002-01-01 05:52 (192.168.1.1)
4)cal
Command:cal
Syntax:cal
Purpose:This command displays the calendar of any specific month of a complete
year.
OUTPUT:
[sudha@rjsplinux ~]$ cal
February 2015
Su Mo Tu We Th Fr Sa
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
5)Date
Command:date
Syntax:date
Purpose:This command is used to display current date and time of the
system.
OUTPUT:
[sudha@rjsplinux ~]$ date
Thr mar 24 7:14:55 IST 2016
Date Options:
[velumani@rjsplinux ~]$ date +%D
01/01/02
[velumani@rjsplinux ~]$ date +%H
06
[velumani@rjsplinux ~]$ date +%M
42
[velumani@rjsplinux ~]$ date +%S
59
[velumani@rjsplinux ~]$ date +%T
06:43:06
[velumani@rjsplinux ~]$ date +%w
2
[velumani@rjsplinux ~]$ date +%a
Tue
[velumani@rjsplinux ~]$ date +%h
Jan
[velumani@rjsplinux ~]$ date +%r
06:43:35 AM
[velumani@rjsplinux ~]$ date +%y

02
6)BC(Binary calculator)
Command:bc
Syntax:bc
Purpose:This command is used in converting number system.
OUTPUT:
[sudha@rjsplinux ~]$ bc
Bc 1.06.95
Copyright 1991-1994,1997,1998,2000,2004,2006 free software
foundation,inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type ‘warranty’.
10+20
30
5*5;8/2
25
4
Integer computation
8/3
O/P:2
Floating point computation
bc
scale=2 scale=3
8/3 8/3
Result=2.66 Result=2.666
To convert binary to decimal
EX:ibase=2
1101
13
Decimal to binary
EX:obase=2
13
1101
Hexadecimal to decimal Decimal to Hexadecimal
EX:obase=16 obase=16
15 10
F A
7)MAN
Command:man
Syntax:man command_name
Purpose:This command is used for getting information for all commands.
EX:man ls
OUTPUT:
[sudha@rjsplinux ~]$ man ls
LS(1) User commands LS(1)
NAME
Ls – list directory contents
SYNOPSIS
Ls[OPTION]...[FILE]...
DESCRIPTION
List information about the FILE’s(the current directory by default).
Sort entries alphabetically if none of –cftuvSUX nor –sort.
Mandatory arguments to long options are mandatory for short options too.
-a,--all
Do not ignore entries starting with.
-A,--almost-all
Do not list implied.and..
--author
With –l,print the author of each file.
-b,--escape
Print C-style escapes for non-graphic characters.
--block-size=SIZE
Use SIZE-byte blocks.see SIZE format below.
-B,--ignore-backups
Do not list implied entried ending with ~
-c with –It:sortby,andshow,ctime(time of last modification of file status
information)
with – l:show ctime and sort by name otherwise:sort by ctime.
8)Passwd
Command: passwd
Syntax: passwd {options} {user_name}
Purpose:To change the current password.
EX: passwd velumani
OUTPUT:
[velumani@rjsplinux ~]$ passwd velumani
passwd: Only root can specify a user name.
9)Uname
Command: uname
Syntax: uname [options]
Purpose: Print information about the current system.
Print certain system information. If no OPTION is specified ,uname assumes
the -s option.
EX: uname -s
OUTPUT:
[velumani@rjsplinux ~]$ uname -s
Linux
[velumani@rjsplinux ~]$ uname -n
rjsplinux
[velumani@rjsplinux ~]$ uname -r
2.6.35.6-45.fc14.i686
[velumani@rjsplinux ~]$ uname -m
i686
[velumani@rjsplinux ~]$ uname -p
i686
[velumani@rjsplinux ~]$ uname -i
i386
[velumani@rjsplinux ~]$ uname -o
GNU/Linux
[velumani@rjsplinux ~]$ uname --version
uname (GNU coreutils) 8.5
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.

Working with files & directories
Directory related commands

1)Pwd(Print working directory)
Command:pwd
Purpose:This command displays the full path name of current directory that
we are workingin.It has no options.
Syntax:pwd
OUTPUT:
[velumani@rjsplinux ~]$ pwd
/home/Velumani
2)Cd(Change directory)
Command:cd
Purpose:we can move around the file system by using the “cd”
command.When “cd” is used with an argument,it changes the current
directory to the directory specified as the argument.
OUTPUT:
[sudha@rjsplinux ~]$ cd first
[sudha@rjsplinux first]$
3)mkdir(make directory)
Command:mkdir
Purpose:This command is used to create directory (or) sub-directory’s.
Syntax:mkdir directory_name
OUTPUT:
[sudha@rjsplinux first]$ mkdir velumani
[sudha@rjsplinux first]$ ls
Velumani ceee icc m1 science co
[sudha@rjsplinux first]$
4)rmdir(Remove directory)
Command:rmdir
Purpose:This command is used to remove directories.
Syntax:rmdir directory_name

OUTPUT:
[sudha@rjsplinux first]$ rm icc
[sudha@rjsplinux first]$ ls
Velumani ceee m1 science co
File related commands
1)Comm
Command:comm.
Purpose:This command compares two sorted files line by line and displays
the instance that are common when this command is executed it executed it
displays 3 columnar output.
Syntax: comm filename1 filename2
Output:
[velumani@rjsplinux ~]$ cat > color1
blue
pink
red
white
^Z
[7]+ Stopped cat > color1
[velumani@rjsplinux ~]$ cat > color2
black
green
orange
red
^Z
[8]+ Stopped cat > color2
[velumani@rjsplinux ~]$ comm color1 color2
black
blue
green
orange
pink
red
white

Note:1st column displays unique lines in the first file (color1: blue,pink,white)
2nd column displays unique lines in the second file (color2:
black,green,orange)
3rd column displays common to both the files.
2)Comparing two files

COMMAND:cmp
PURPOSE:This command is used to compare two files to know whether they are
identical (or) not.
SYNTAX:cmp filename1 filename2
OUTPUT:
[velumani@rjsplinux ~]$ cmp color1 color2
color1 color2 differ: byte 3, line 1
3)Diff
Command:diff
Purpose:This command compares two text file and bring the lines that are
different.It uses an index that all the line that differs in two files.
Syntax:diff filename1 filename2
Output:
[velumani@rjsplinux ~]$ cat f5
I like sunday
I like to use mobile
I like to continue my studies
[velumani@rjsplinux ~]$ cat f6
I like sunday
I like to use Tablet
I like to continue my education
I like to continue my studies
[velumani@rjsplinux ~]$ diff f5 f6
2c2,3
< I like to use mobile
---
> I like to use Tablet
> I like to continue my education

4)tar
Command:tar
Purpose:The archival program this command is used for creating a disk achieve
which
contains a group of files or an entire directory structure.
Following list shows the key option used for tar command.
-c:-creates an archive.
-x:-extract files from archive.
-t:-display files in archive.
Syntax:tar –c filename
Output:
[sudha@rjsplinux ~]$ tar –c os
Os0000664000105700010570000000003107425644504010634 0ustar One
two
Three four five
5)Umask (User mask)

COMMAND: umask
PURPOSE: The user file-creation mode mask (umask) is use to determine the file
permission for newly created files. It can be used to control the default file
permission for new files.
SYNTAX:umask [-p] [-s] [mod]
OUTPUT:
[sudha @rjsplinux first]$ umask –p 777
[sudha @rjsplinux first]$ ls –l
Total 16
drwxrwxr-x 2 sudha sudha 4096 Mar 03 7:30 abhi
drwxrwxr-x 2 sudha sudha 4096 Mar 03 7:31 ceee
drwxrwxr-x 2 sudha sudha 4096 Mar 04 M1
drwxrwxrwx 2 sudha sudha 4096 Mar 04 sci
6)WC(Word count)
COMMAND:wc
PURPOSE:This command counts number of statements (or) lines,words and
character which is written in the file.
SYNTAX:wc filename
EX:wc velumani

OUTPUT:
[velumani@rjsplinux ~]$ cat > velumani
I like to play cricket
Raina is my favourite player
India won the 2011 world cup
^Z
[11]+ Stopped cat > velumani
[velumani@rjsplinux ~]$ wc velumani
3 16 81 velumani

Manipulating file permission using chmod command
1)chmod(Change mode)
COMMAND:chmod
PURPOSE:This command is used to set the permission of one (or) more files for
all 3 categories of users that is user group and other.It can be run only by the users
and super user.
Relative permission
SYNTAX:chmod categoryoperation permission filename
OUTPUT:
wp
mc
gc
[velumani@rjsplinux ~]$ ls -l abc
-rw-r--r-- 1 velumani Velumani 9 Jan 1 06:11 abc
[velumani@rjsplinux ~]$ chmod ugo+x abc
-rwxr-xr-x 1 velumani Velumani 9 Jan 1 06:11 abc
[velumani@rjsplinux ~]$ chmod u-x abc
-rw-r-xr-x 1 velumani Velumani 9 Jan 1 06:11 abc
Absolute permission
SYNTAX:chmod expression filename
OUTPUT:
[velumani@rjsplinux ~]$ cat > sci
hello
^Z
[12]+ Stopped cat > sci
[velumani@rjsplinux ~]$ ls -l sci
-rw-r--r-- 1 velumani Velumani 6 Jan 1 07:35 sci
[velumani@rjsplinux ~]$ chmod 777 sci
[velumani@rjsplinux ~]$ ls -l sci
-rwxrwxrwx 1 velumani Velumani 6 Jan 1 07:35 sci

2) Chown (change ownership)

Command: chown
Purpose: To change the ownership of a file.
Syntax: chown username filename
OUTPUT:
[velumani@rjsplinux ~]$ su
Password:
[root@rjsplinux Velumani]# chown srikanth f1
[root@rjsplinux Velumani]# ls -l f1
-rw-r--r-- 1 srikanth Velumani 22 Jan 1 2002 f1

Manipulating Hardlink and Softlink using ln command
Hardlink
Ln (Link)
COMMAND: ln
PURPOSE: This command is used to have multiple names for a file.
SYNTAX: ln filename targetlink
OUTPUT:
[velumani@rjsplinux ~]$ echo 'This is an example for hardlink' > hl
[velumani@rjsplinux ~]$ ln hl hl1
[velumani@rjsplinux ~]$ ls -li hl1 hl
262461 -rw-r--r-- 2 velumani Velumani 32 Jan 1 07:05 hl
262461 -rw-r--r-- 2 velumani Velumani 32 Jan 1 07:05 hl1
[velumani@rjsplinux ~]$ cat hl
This is an example for hardlink
[velumani@rjsplinux ~]$ cat hl1
This is an example for hardlink
Softlink/Symbolic link/system link

Ln (Link)
COMMAND: ln
PURPOSE: This command is used as a special file that contains a reference to a
another file.
SYNTAX: ln filename linkname
OUTPUT:
[velumani@rjsplinux ~]$ ln -s file1 link1
[velumani@rjsplinux ~]$ ls -l file1 link1
-rw-r--r-- 1 velumani Velumani 23 Jan 1 06:04 file1
lrwxrwxrwx 1 velumani Velumani 5 Jan 1 07:19 link1 -> file
[velumani@rjsplinux ~]$ cat file1
apple
egg
fish
grapes
[velumani@rjsplinux ~]$ cat link1
apple
egg
fish
grapes
Learn to use vi-editor

vi insert mode
Once you issue a vi insert, append, or open command, you will be in vi

insert mode. If you're working with a modern vi or vim implementation, your vi editor is
typically configured to show the current mode of operation, so when you go into insert
mode, you'll see a text string like this on the last line of your vi editor window:
-- INSERT --
At this point you can (a) type text into your file and (b) use the arrow keys to navigate
around your file just as you would do with any other text editor. (There may be some
complications with older Unix systems, like HP-UX systems, but this statement is
generally true.)
A very important concept to know is that when you're in vi insert mode, but you want to
switch back to vi command mode, you easily move back to command mode by pressing
the [Esc] key. This command is so important, I'll show it again:
[Esc]
This command is very common, and I often see expert vi users press the [Esc] key several
times in a row. They usually do this
(a) to be sure they hit the key and they're really back in command mode, and
(b) to hear the beep from the computer, which happens when you press the [Esc] key
when you're already in vi command mode.
This seems to serve as a form of feedback which assures them that they're in
command mode.
Command Mode: When vi starts up, it is in Command Mode. This mode is where vi
interprets any characters we type as commands and thus does not display them in the
xterm window. This mode allows us to move through a file, and to delete, copy, or paste a
piece of text. To enter into Command Mode from any other mode, it suffices to press
the [Esc] key. If we press [Esc] when we are already in Command Mode, then vi will beep
or flash the screen.
Input Mode: In Input Mode, vi accepts keystrokes as text and displays the text as it is
entered from the keyboard. vi must be in Input Mode before we can insert text into a file.
To enter into Input Mode, we need to put vi into Command Mode and type the key [i].
Line Mode: Line Mode is invoked by typing a colon [:] or a slash [/] while vi is in
Command Mode. The cursor will jump to the last line of the screen and vi will wait for a
command.

Invoking vi
Command Function
vi filename Edit filename starting at line 1
vi +n filename Edit filename starting at line n
vi + filename Edit filename starting at the last line
Entering Text
Command Function
cmd[a] To insert text just after the cursor
cmd[I] To add text to the beginning of the current line
cmd[A] To add text to the end of the current line
cmd[O] To insert a line just above the current line
cmd[o] To insert a line just below the current line
Deleting and Cutting Blocks of Text

Command Function
cmd[x] To delete a character at the cursor
cmd[X] To delete a character preceding the cursor
cmd[d][w] To delete or cut a word at the cursor
cmd[d][b] To delete or cut a word preceding the cursor
To cut from the current character to the end of the
cmd[d][$] or cmd[D]
line
To cut from the current character to the beginning of
cmd[d][^]
the line
cmd[d][)] To delete or cut a sentence at the cursor
cmd[d][(] To delete or cut a sentence preceding the cursor
cmd[d][}] To delete or cut a paragraph at the cursor
cmd[d][{] To delete or cut a paragraph preceding the cursor
cmd number[D] or cmd To cut several lines, where number is the number of
number [dd] lines that you want to yank

Copying and Pasting Text

Preceding, left of the
At, right of the cursor Function
cursor
cmd[y][w] cmd[y][b] Yank word
cmd[y][$] or cmd[Y] cmd[y][0] Yank whole line
cmd[p] cmd[P] Put contents into file
Saving the File and Quitting vi
Command Function
cmd[:][w] To just save the file
cmd[:][q] To quit the file after you have saved it
cmd[:][w][q] To save and quit vi
To retain the original version of the file and save the
cmd[:][w] newfile
changes to another file called newfile
cmd [:][q][!] To quit vi without saving changes

Simple filters-head, tail, cut, paste, sort, uniq, tr, pr
1)Head
COMMAND:Head
PURPOSE:Outputs the first 10 lines of specified file.This command displays the
top of the file(10 lines from first)when used without an option.
SYNTAX:head filename
OUTPUT:
[velumani@rjsplinux ~]$ head alpha
a
b
c
d
e
f
g
h
i
j
[velumani@rjsplinux ~]$ head -3 alpha
a
b
c
2)Tail
COMMAND:Tail
PURPOSE:Outputs the last 10 lines of the file.This command display last 10 lines
when used without option.
SYNTAX:tail filename
OUTPUT:
[velumani@rjsplinux ~]$ tail alpha
q
r
s
t
u
v
w
x
y
z
[velumani@rjsplinux ~]$ tail -3 alpha
x
y
z
3)Cut(Spliting a file vertically)
COMMAND:Cut
PURPOSE:We can extract both columns and fields from the file columns are
separated in the –c option.
SYNTAX:cut [option] filename
OUTPUT:
[velumani@rjsplinux ~]$ cat > emp
Empid|Empname|Des|Salary
11|arya|Manager|25000
12|bharath|CEO|55000
13|ramakrishna|vicepresident|60000
14|dany|engineer|30000
[8]+ Stopped cat > emp
[velumani@rjsplinux ~]$ cut -d '|' -f2 emp
Empname
arya
bharath
ramakrishna
dany
[velumani@rjsplinux ~]$ cut -d '|' -f3 emp
Des
Manager
CEO
vicepresident
engineer
[velumani@rjsplinux ~]$ cut -d '|' -f2-4 emp
Empname|Des|Salary
arya|Manager|25000
bharath|CEO|55000
ramakrishna|vicepresident|60000
dany|engineer|30000
[velumani@rjsplinux ~]$ cut -c 1-10 emp
Empid|Empn
11|arya|Ma
12|bharath
13|ramakri
14|dany|en
[velumani@rjsplinux ~]$ cut -c 1-5 emp
Empid
11|ar
12|bh
13|ra
14|da
4)Paste
COMMAND:Paste
PURPOSE:What we cut with cut command can be pasted back with the paste
command vertically rather than horizontally.
SYNTAX: paste –d cutlist1 cutlist2
OUTPUT:
[velumani@rjsplinux ~]$ cut -d '|' -f2 emp > list1
[velumani@rjsplinux ~]$ cut -d '|' -f3 emp > list2
[velumani@rjsplinux ~]$ cat list1
Empname
arya
bharath
ramakrishna
dany
[velumani@rjsplinux ~]$ cat list2
Des
Manager
CEO
vicepresident
engineer
[velumani@rjsplinux ~]$ paste list1 list2
Empname Des
arya Manager
bharath CEO
ramakrishna vicepresident
dany engineer

5)Sort: Ordering a file

COMMAND:Sort
PURPOSE: Arranging the contents of a file in order. It identifies the fields and it
can sort a specified field.
SYNTAX:sort filename
OUTPUT:
[velumani@rjsplinux ~]$ cat color1
blue
pink
red
white
[velumani@rjsplinux ~]$ sort color1
blue
pink
red
white
Sort Options: (-r) Reverse order

COMMAND:Sort
PURPOSE: Arranging the contents of a file in reverse order.
SYNTAX:sort [options] filename
OUTPUT:
[velumani@rjsplinux ~]$ cat color1
blue
pink
red
white
[velumani@rjsplinux ~]$ sort -r color1
white
red
pink
blue
Sorting on keys(-k)
COMMAND:Sort
PURPOSE: Arranging the contents of a specific column in an order.
SYNTAX:sort [options] filename

OUTPUT:
[velumani@rjsplinux ~]$ cat > rjsp1
CS 11 DE
CP 12 BS
ME 06 SOM
EC 01 CEEE
^Z
[5]+ Stopped cat > rjsp1
[velumani@rjsplinux ~]$ sort -k2 rjsp1
EC 01 CEEE
ME 06 SOM
CS 11 DE
CP 12 BS
[velumani@rjsplinux ~]$ sort -k3 rjsp1
CP 12 BS
EC 01 CEEE
CS 11 DE
ME 06 SOM
6)Uniq
COMMAND: Uniq
PURPOSE: When we concatenate a merge files that duplicate the entries. The uniq
compare adjacent lines in the sorted files and when used in different options
displays the single occurrence.
SYNTAX: uniq [options] filename
OPTIONS DESCRIPTION
-C Count occurrence of each line.
-d Prints only duplicate lines.
-D Prints all duplicate lines.
-i Ignore case when computing.
-u Prints only unique lines.
OUTPUT:
[velumani@rjsplinux ~]$ cat computer
computer is an electronic device.
COMPUTER IS AN ELECTRONIC DEVICE.
computer is easy to use.
computer is a dumb machine.
[velumani@rjsplinux ~]$ uniq -c computer

2 computer is an electronic device.
1 COMPUTER IS AN ELECTRONIC DEVICE.
1 computer is easy to use.
2 computer is a dumb machine.
[velumani@rjsplinux ~]$ uniq -u computer

COMPUTER IS AN ELECTRONIC DEVICE.
[velumani@rjsplinux ~]$ uniq -d computer

[velumani@rjsplinux ~]$ uniq -D computer

[velumani@rjsplinux ~]$ uniq -i computer

7)Tr(Translating character)
COMMAND:Tr
PURPOSE:This command is used to translate a character. Tr command take input
from standard input.It does not take filename an arguments.
SYNTAX:tr option expression1 expression2 symbols
OUTPUT:
[sudha@rjsplinux ~]$ cat > symbols
| pipe
*astric
^ caret
^Z
[1]+ stopped cat > symbols

[sudha@rjsplinux ~]$ tr ‘*’ ‘~’ < symbols
| pipe
~ astric
^ caret
8)Pr
COMMAND:Pr
PURPOSE:This command format inputs to print the pr command prepares file for
printing by adding header,footers & formatted text.
SYNTAX:pr filename
OUTPUT:
[sudha@rjsplinux ~]$ pr xyz
2002-01-09 6:43 xyz page1
A
B
C
D
E
F
G
H
I
J
Pr options
Character Description
1)-t To suppress the header and footer.
2)-dp Double spaces input.
3)-n Number lines.
4)-h Header of our option.
5)-on Offset lines by n spaces and increases left
Margin of page sets the page length.
6)-l sets the page length.
EX:pr –l 54 velu

Expressions and search patterns. (dot operator),*,^,+,?,grep,egrep,fgrep
1)GREP (Global Regular Expression Print)

COMMAND:grep
PURPOSE:grep scans its input for its pattern and displays the selected patterns, the
line number or the filename where the pattern occurs.
SYNTAX:grep option pattern filename.
OUTPUT:
[velumani@rjsplinux ~]$ cat > students
1 cs arun
2 cs bhavya
3 cp varun
4 me ajith
5 CS vikram
^Z
[1]+ Stopped cat > students
[velumani@rjsplinux ~]$ grep 'cs' students
1 cs arun
2 cs bhavya
GREP OPTIONS
a) ignoring case(-i)
COMMAND:grep
PURPOSE:grep option –i(ignore),which ignores case for the pattern matching.
OUTPUT:
[velumani@rjsplinux ~]$ grep -i 'cs' students
1 cs arun
2 cs bhavya
5 CS vikram
b) deleting the line(-n)

COMMAND:grep
PURPOSE:this option is used to display the line number containing the pattern along
with the lines.
OUTPUT:
[velumani@rjsplinux ~]$ grep -n 'me' students
4:4 me ajith

c) delecting lines(-v)
COMMAND:grep
PURPOSE:this option selects all the lines except lies containing the pattern
OUTPUT:
[velumani@rjsplinux ~]$ grep -v 'me' students
1 cs arun
2 cs bhavya
3 cp varun
5 CS vikram
d) displaying filename(-l)
COMMAND:grep
PURPOSE:This option displays only the names of files containing the pattern.
OUTPUT:
[velumani@rjsplinux ~]$ grep -l 'cs' students
Students
e) counting lines containing patterns (-c)

COMMAND:grep
PURPOSE:This option counts the number of lines containing the patterns.
OUTPUT:
[velumani@rjsplinux ~]$ grep -c 'me' students
1
2)EGREP(Extended Global Regular Expressions Print)

COMMAND:egrep
PURPOSE:This command extends grep pattern matching capability.it offers all the
option of grep but it moves useful features.Its the facilts to specify more than one
pattern for search.each pattern is separated from the other by a pipe(|)symbol.
SYNTAX:egrep ‘pattern’ | ‘pattern2’ filename..
OUTPUT:
[velumani@rjsplinux ~]$ egrep 'c|s' students
1 cs arun
2 cs bhavya
3 cp varun

OPTIONS:
a) To match one or more occurrence (+)
COMMAND:egrep
PURPOSE:This character matches one or more occurrence of the previous
character.
SYNTAX: command pattern character filename
OUTPUT:
[velumani@rjsplinux ~]$ egrep cs+ students
1 cs arun
2 cs bhavya
b) To match zero or one occurrence(?)
COMMAND:egrep
PURPOSE:This character matches zero or one occurrence of the previous
character.
SYNTAX: command pattern character filename
OUTPUT:
[velumani@rjsplinux ~]$ egrep z? students
1 cs arun
2 cs bhavya
3 cp varun
4 me ajith
5 CS vikram
2)FGREP(Fixed GREP)
COMMAND:fgrep
PURPOSE:This command is used to extract only fixed string without the use of any
regular expression.
SYNTAX:fgrep ‘fixed string’ filename..
OUTPUT:
[velumani@rjsplinux ~]$ cat health
Apple is a good fruit.
Apple is grown in kashmir
I like mangoes
An Apple a day keeps the doctor away
[velumani@rjsplinux ~]$ fgrep "Apple" health
Apple is a good fruit.
Apple is grown in kashmir
An Apple a day keeps the doctor away

Following list describes various character for pattern matching
CHARACTER DESCRIPTION
1)(Asterisk) Its refers to immediately preceeding character.
SYNTAX:Grep g* filename
[velumani@rjsplinux ~]$ grep j* dot
id name age
1 manju 21
2 venu 20
3 jaga 19
4 hari 19
5 siva 18
2) .(Dot) A dot matched a single character.

SYNTAX:Grep 1.filename
EX:Grep 1. students
[velumani@rjsplinux ~]$ grep 1. students
1 cs arun
3) ^(Caret) A ^(Caret symbol is used for matching at the

beginning of the line.
SYNTAX:Grep ^2 filename
[velumani@rjsplinux ~]$ grep ^2 dot
2 venu 20
4) $(Dollar) A $(Dollar) symbol is used for matching at the

end of the line.
SYNTAX:Grep $ filename.
[velumani@rjsplinux ~]$ grep 9$ dot
3 jaga 19
4 hari 19

Process management commands

Process status(ps)
COMMAND:ps
PURPOSE:This command displays some process attributes and the processes
associated with the user at the terminal.
SYNTAX:ps
OUTPUT:
[velumani@rjsplinux ~]$ ps
PID TTY TIME CMD
2096 pts/6 00:00:00 bash
2442 pts/6 00:00:00 ps
Identifying Process
COMMAND: ls
PURPOSE: This command is used to identify all currently running process.
SYNTAX: ls /proc
OUTPUT:
[velumani@rjsplinux ~]$ ls /proc
1 1308 1739 1850 29 49 992 kallsyms self
10 131 1745 1852 3 5 acpi kcore slabinfo
1005 132 1762 1854 30 50 asound keys softirqs
1018 14 1768 1892 31 51 buddyinfo key-users stat
1019 1428 1770 1893 315 528 bus kmsg swaps
1026 1429 1773 19 32 529 cgroups kpagecount sys
1034 1430 1775 1908 322 6 cmdline kpageflags sysrq-trigger
1042 1431 1777 1910 33 7 cpuinfo latency_stats sysvipc
1069 1434 1789 1911 331 712 crypto loadavg timer_list
1079 1476 1792 1934 332 761 devices locks timer_stats
1080 15 18 1938 333 762 diskstats mdstat tty
1087 1544 1807 1941 34 763 dma meminfo uptime
11 16 1819 2 35 764 dri misc version
1100 1658 1820 20 384 765 driver modules vmallocinfo
1142 1663 1825 21 394 766 execdomains mounts vmstat
1161 1667 1829 22 4 8 fb mtrr zoneinfo
1162 1686 1833 23 405 809 filesystems net
12 1694 1834 24 41 9 fs pagetypeinfo
1222 17 1836 25 42 914 interrupts partitions
1257 1707 1839 26 44 947 iomem sched_debug
13 1718 1841 27 45 966 ioports schedstat
130 1730 1843 28 48 980 irq scsi
Process options
1)-f(Full listing)
COMMAND:ps
PURPOSE:This option is used to get all detailed listing which also shows the
parent of every process.
SYNTAX:ps –f
OUTPUT:
[velumani@rjsplinux ~]$ ps -f
UID PID PPID C STIME TTY TIME CMD
velumani 1911 1910 0 05:36 pts/0 00:00:00 -bash
velumani 1938 1911 0 05:37 pts/0 00:00:00 less
velumani 1942 1911 1 05:44 pts/0 00:00:00 ps -f
Where
UID: User ID
PID: Process ID
C:Indicates the amount of CPU time consumed by the process.
STIME: Shows the time of process started.
TTY(Terminal): In which the process is executing.
TIME: Shows the total CPU time used by the process.
CMD: Display the command.
2)-u(User)
COMMAND: ps
PURPOSE: Displays the process of a user.
SYNTAX: ps –u username
OUTPUT:
[velumani@rjsplinux ~]$ ps -u velumani
PID TTY TIME CMD
1911 pts/0 00:00:00 bash
1938 pts/0 00:00:00 less
1946 pts/0 00:00:00 ps
3)-a(All users)
COMMAND: ps
PURPOSE: This options list the process of all users but does not displays the
system process.
SYNTAX: ps –a

OUTPUT:
[velumani@rjsplinux ~]$ ps -a
PID TTY TIME CMD
2841 pts/5 00:00:00 vim
2974 pts/1 00:00:00 vim
3345 pts/0 00:00:00 vim
3428 pts/7 00:00:00 bash
3429 pts/7 00:00:00 pk-command-not-
3435 pts/7 00:00:00 bash
3543 pts/13 00:00:00 bash
3544 pts/13 00:00:00 pk-command-not-
3545 pts/8 00:00:00 vim
3650 pts/0 00:00:00 vim
3846 pts/5 00:00:00 vim
3848 pts/5 00:00:00 vim
3849 pts/5 00:00:00 vim
3934 pts/12 00:00:00 vim
3937 pts/3 00:00:00 vim
3938 pts/11 00:00:00 vim
3965 pts/10 00:00:00 ps
4)-e / -A (System processes)

COMMAND:ps
PURPOSE: To display the number of system processes keep running all the times
SYNTAX:ps -e or -A
OUTPUT:
[velumani@rjsplinux ~]$ ps -A
PID TTY TIME CMD
1? 00:00:01 init
2? 00:00:00 kthreadd
3? 00:00:00 ksoftirqd/0
4? 00:00:00 migration/0
5? 00:00:00 watchdog/0
6? 00:00:00 migration/1
7? 00:00:00 ksoftirqd/1
8? 00:00:00 watchdog/1
9? 00:00:00 events/0
10 ? 00:00:00 events/1
11 ? 00:00:00 cpuset
12 ? 00:00:00 khelper
13 ? 00:00:00 netns
Running process in background
1)&:(No logging out)

COMMAND: &
PURPOSE: This operator is used to run a process in the background.
SYNTAX: command filename operator
OUTPUT:
[velumani@rjsplinux ~]$ sort employee &
[5] 1956
[4] Done sort employee
2)Nohup(No hang up:Logout out safely)

COMMAND: nohup
PURPOSE: This command when prefix to a command it permits execution of a process
even after user has logout.
SYNTAX: nohup command filename operator
OUTPUT:
[velumani@rjsplinux ~]$ nohup sort f1 &
[2] 1988
[velumani@rjsplinux ~]$ nohup: ignoring input and appending output to `nohup.out'
[2]- Done nohup sort f1
Process termination
Kill: Premature termination of a process.

COMMAND: Kill
PURPOSE: The kill command terminates a process. It uses one (or) more pid’s as its
arguments.
SYNTAX: kill pid
EX: kill 1766

Changing process priority
Nice: Job execution with low priority

COMMAND: nice
PURPOSE: This command is used to reduce the priority of jobs.
SYNTAX: nice command filename
OUTPUT:
[velumani@rjsplinux ~]$ nice wc f5
3 14 65 f5
Scheduling process (Usage of sleep and wait commands)
1)AT:ONE-TIME EXECUTION
COMMAND:The AT command takes time as its argument, the job is to be
executed and displays the AT > prompt.
The input has to be supplied from the old at 14:08
AT > filename
[Ctrl+D]
SYNTAX:AT time
EX: [velumani@rjsplinux ~]$ at noon
at> f2
at> <EOT>
job 71 at Tue Jan 1 12:00:00 2002
2)Batch: Execute in batch queue

COMMAND:Batch
PURPOSE: The batch command also schedules jobs for later execution.
SYNTAX:Batch < filename
OUTPUT:
[velumani@rjsplinux ~]$ batch < f5
job 147 at Tue Jan 1 06:20:00 2002

Linux system administration
Managing file system

In this file system they are two types they are as follows
1)Mount: Mounting file system
COMMAND:Mount
PURPOSE: This command is used to mount file system.
SYNTAX:mount
OUTPUT:
[velumani@rjsplinux ~]$ mount
/dev/mapper/vg_rjsplinux-lv_root on / type ext4 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
/dev/sda1 on /boot type ext4 (rw)
/dev/mapper/vg_rjsplinux-lv_home on /home type ext4 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
2)Umount: Unmounting file system

COMMAND:Umount
PURPOSE:Umount file system.we can umount remote resourse by using umount
command.
SYNTAX:Umount.
OUTPUT:
[velumani@rjsplinux ~]$ umount
Usage: umount -h | -V
umount -a [-d] [-f] [-r] [-n] [-v] [-t vfstypes] [-O opts]
umount [-d] [-f] [-r] [-n] [-v] special | node...

Disk management utilities

In order to check how much disk space is available in each file system in a
computer and to make sure that enough space save our file.
UNIX OFFERS SOME DISK MANAGEMENT UTILITIES
1)Df (Disk Free): Reporting Free Space

COMMAND: df
PURPOSE: This command reports the amount of free space available for each file
system.
SYNTAX:df
OUTPUT:
[velumani@rjsplinux ~]$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/mapper/vg_rjsplinux-lv_root
51606140 5335476 43649224 11% /
tmpfs 250124 88 250036 1% /dev/shm
/dev/sda1 495844 29024 441220 7% /boot
/dev/mapper/vg_rjsplinux-lv_home
187232148 328648 177392588 1% /home
2)Du: Disk Usage

COMMAND:du
PURPOSE: This command is used to check the information of disk usage of files
and directories on a machine.
SYNTAX:du
OUTPUT:
[velumani@rjsplinux ~]$ du
4 ./.gnome2_private
68 ./.gconfd
4 ./.gvfs
4 ./.mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}
8 ./.mozilla/extensions
4 ./.mozilla/firefox
4 ./.mozilla/plugins
[2]+ Stopped du

3)fdisk (Fixed Disk or Format Disk): Creating partitions

COMMAND:fdisk
PURPOSE: With the help of fdisk command you can view, create, resize, delete,
change, copy and move partitions on a hard drive using its own user-friendly text-
based menu driven interface.
SYNTAX:fdisk.
OUTPUT:
[velumani@rjsplinux ~]$ fdisk
Usage:
fdisk [options] <disk> change partition table
fdisk [options] -l <disk> list partition table(s)
fdisk -s <partition> give partition size(s) in blocks
Options:
-b <size> sector size (512, 1024, 2048 or 4096)
-c[=<mode>] compatible mode: 'dos' or 'nondos' (default)
-h print this help text
-u[=<unit>] display units: 'cylinders' or 'sectors' (default)
-v print program version
-C <number> specify the number of cylinders
-H <number> specify the number of heads
-S <number> specify the number of sectors per track
4)su (Super User)

COMMAND:su
PURPOSE:We can log-on into a unix machine as a user and then issue the ‘su’
command to super user(root).
SYNTAX:su
OUTPUT:
[velumani@rjsplinux ~]$ su
Password:
[root@rjsplinux Velumani]#
5)Useradd(Adding a user)
COMMAND: useradd
PURPOSE: This command adds a new user to the Linux System Administrator
with some specific properties, limitations or comments.
SYNTAX: useradd directory username.

OUTPUT:
[velumani@rjsplinux ~]$ useradd
To List all usernames: awk -F: '{print $1}' /etc/passwd
6)userdel (Deleting a user)

COMMAND: userdel
PURPOSE: The userdel command deletes a user accountand all associated files.
userdel is a low-level utility for removing users.
SYNTAX:userdel directory username
7)groupadd: Adding a group

COMMAND:groupadd
PURPOSE: This command is used to place a user in a new group.An entry for the
group has to be created first in /etc/ group.
SYNTAX:groupadd groupname
EX: groupadd CS-2014-batch
8)groupdel: Deleting a group

COMMAND:groupdel
PURPOSE: If a group is no longer required we can delete it.
SYNTAX:groupdel group name
EX:groupdel CS-2014-batch
9)groupmod(modifier)
COMMAND:groupmod
PURPOSE:It is used to modify a groupname.
SYNTAX:groupmod –n new_group_nameold_group_name
Ex:groupmod –n RCB CSK
10)Tar (the archival program)

COMMAND: tar
PURPOSE: This command is used to back-up individual files and directory.we can
mount the directory which we want the date to perform back-up tar and wait for a
restore the directory.

Advanced filter (Sed & Awk)
1)Sed (The Stream editor)

COMMAND: sed
PURPOSE: This command is used to perform basic text transformations on an
input
stream.(A file or input from a pipeline)
SYNTAX: sed [Options] ‘address action’ filename
Where
d: It deletes the specified line.
p: It prints the specified line.(Duplicate line)
q: Quits after the line number specified in the instruction.
$p: Prints the last line of a file.(Duplicate line)
OUTPUT:
[velumani@rjsplinux ~]$ cat fruits
kiwi
grapes
apple
mango
orange
[velumani@rjsplinux ~]$ sed '1d' fruits
grapes
apple
mango
orange
[velumani@rjsplinux ~]$ sed '2p' fruits
kiwi
grapes
grapes
apple
mango
orange
kiwi
grapes
apple
mango
mango
orange

kiwi
grapes
apple
mango
mango
orange
kiwi
kiwi
grapes
apple
mango
orange
[velumani@rjsplinux ~]$ sed '$p' fruits
kiwi
grapes
apple
mango
orange
orange
[velumani@rjsplinux ~]$ sed 'p' fruits
kiwi
kiwi
grapes
grapes
apple
apple
mango
mango
orange
orange

2) Awk (Aho, Weinberger, and Kernighan)

COMMAND: awk
PURPOSE: This command is used for processing or analyzing text files which is
organized by rows and columns
SYNTAX: awk options ‘selection-criteria {actions}’ filename
Where
Selection-criteria:It filter input and selects lines for the actions.(form of
addressing)
{}:Components is enclosed within curly braces.
OUTPUT:
[velumani@rjsplinux ~]$ cat rjsp
Harish : CS
Jaga : CS
Ram : ME
Siva : CS
Venu : CS
Srini : EE
[velumani@rjsplinux ~]$ cat rjsp | awk 'begin {fs="Harish"} -f fs {print $1}'
Harish
Jaga
Ram
Siva
Venu
Srini
[velumani@rjsplinux ~]$ cat rjsp | awk 'begin {fs="Harish"} -f fs {print $1,$3}'
Harish CS
Jaga CS
Ram ME
Siva CS
Venu CS
Srini EE

PART- B
SHELL SCRIPTS & C
PROGRAMS

1. Write a shell script to display current date, time, username and directory.
#!/bin/bash
echo “Hello,$LOGNAME”
echo "Current date is `date`"
echo "Username is `who i am`"
echo "Current directory `pwd`"
OUTPUT:
[velumani@rjsplinux ~]$ bash pgm1
Current date is Tue Jan 1 05:43:37 IST 2002
Username is velumani pts/2 2002-01-01 05:39 (192.168.1.1)
Current direcotry /home/Velumani

• Currently logged user name and his log name
• Current shell
• Your home directory
#!/bin/bash
echo "user name:$USER"
echo "Logname:$LOGNAME"
echo "Home directory:$HOME"
echo "current shell:$SHELL"
OUTPUT:
user name:velumani
Logname:velumani
Home directory:/home/Velumani
current shell:/bin/bash

3.Write shell script to show various system configuration like:

• Your operating system type
• Your current path setting
• Your current working directory
• Show all available shells
#!/bin/bash
echo "our OS type:$OSTYPE"
echo "Path:$PATH"
echo "Current working directory:$PWD"
OUTPUT:
our OS type:linux-gnu
Path:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/Velumani/b
in
Current working directory:/home/Velumani
4.Write a Shell script to accept any two file names and check their file permissions.
#!/bin/bash
echo "Enter two filenames"
read file5
read file6
echo "File permissions are:"
ls -l $file5
ls -l $file6
OUTPUT:
Enter two filenames
rjsp
velu
File permissions are:
-rw-rw-r--. 1 student student 62 Feb 23 00:48 rjsp
-rwxrwxr-x. 1 student student 16 Mar 5 22:45 velu

5.Write a Shell script to read a file name and change the existing file permissions.
#!/bin/bash
echo "Enter the filename:"
read file6
ls -l $file6
chmod ugo+x $file6
echo "After change:"
ls -l $file6
OUTPUT:
Enter the filename:
file6
-rw-rw-r--. 1 velumani Velumani 22 Jan 1 07:15 file6
After change:
-rwxrwxr-x. 1 velumani Velumani 22 Jan 1 07:15 file6
6.Write a C-program to fork a child process and execute the given Linux commands.
#include<stdio.h>
#include<stdlib.h>
main()
{
system("ls");
system("cal");
system("logname");
system("pwd");
}
OUTPUT:
[velumani@rjsplinux ~]$ gcc pgm7.c
[velumani@rjsplinux ~]$ ./a.out
1st details f2 file7 pgm4 recipe smitha
2nd Documents file11 filen pgm5 renu student
abc Downloads file2 health pgm6 rjsp Templates
amc example file33 Music pgm7.c rjsp.sym velu
a.out example1 file5 pgm1 Pictures shanth velu1
Desktop f1 file6 pgm3 Public shopping Videos

January 2002
Su Mo Tu We Th Fr Sa
1 2 3 4 5
6 7 8 9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31
velumani
/home/Velumani
7.Write a C-program to fork a child process, print owner process ID and its parent
process ID.
#include<stdio.h>
#include<sys/types.h>
main()
{
printf("\n\t PID=%d\n\t Child PID=%d\n\n Parent
PID=%d\n\n\n",getpid(),getppid(),fork());
}
OUTPUT:
PID=2237
Child PID=1898
Parent PID=2238
PID=2238
Child PID=2237
Parent PID=0

8.Write a C-program to prompt the user for the name of the environment variable,
check its validity and print an appropriate message.
#include<stdio.h>
int main(int argc,char **argv,char **env)
{
while(*env)
printf("%s\n",*env++);
return 0;
}
OUTPUT:
REMOTEHOST=192.168.1.1
HOSTNAME=rjsplinux
SHELL=/bin/bash
TERM=ansi
HISTSIZE=1000
USER=velumani
LS_COLORS=rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40
;33;01:cd
=40;33;01:or=40;31;01:mi=01;05;37;41:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow
=34;4
2:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arj=01;31:*.taz=01;31:*.lzh=01;31:
*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;3
1:
*.gz=01;31:*.lz=01;31:*.xz=01;31:*.bz2=01;31:*.tbz=01;31:*.tbz2=01;31:*.bz=01;
31
:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=
01
;31:*.rar=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.jp
g
=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=
01;35:
*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg
=0
1;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=
01;35:*

.m2v=01;35:*.mkv=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35
:*.vob=01
;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:
*.flc
=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.x
wd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.axv=01;35:*.anx=01;35:*.ogv
=01;35
:*.ogx=01;35:*.aac=01;36:*.au=01;36:*.flac=01;36:*.mid=01;36:*.midi=01;36:*.m
ka=
01;36:*.mp3=01;36:*.mpc=01;36:*.ogg=01;36:*.ra=01;36:*.wav=01;36:*.axa=01;
36:*.o
ga=01;36:*.spx=01;36:*.xspf=01;36:
MAIL=/var/spool/mail/velumani
PATH=/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/Velumani
/bin
PWD=/home/Velumani
LANG=en_US.UTF-8
KDE_IS_PRELINKED=1
KDEDIRS=/usr
SSH_ASKPASS=/usr/libexec/openssh/gnome-ssh-askpass
HISTCONTROL=ignoredups
SHLVL=1
HOME=/home/Velumani
LOGNAME=velumani
LESSOPEN=|/usr/bin/lesspipe.sh %s
G_BROKEN_FILENAMES=1
_=./a.out

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LINUX LAB (15CS47P) 2015 CURRICULLUM

LINUX LAB MANUAL

FOR 4th Sem CS & E

For Any Feedback Contact

RJS POLYTECHNIC, BANGALORE-34. Page 1

List of Graded Practical Exercises

1. Introduction- Linux Architecture- Shell, Kernel, System calls. Linux installation-

3. Working with files & directories.

∑ Directory related Commands – pwd, mkdir, rmdir, cd, ls

∑ Manipulating Absolute paths and Relative paths using cd command.

4. Basic File attributes.

∑ File Permissions: Absolute and Relative permissions

∑ Manipulating File permissions using chmod command

∑ Manipulating File Ownership using chown command

5. Learn to use vi editor.

∑ Input mode commands.

∑ Command mode commands.

7. Expressions & search patterns .(dot operator), *, ^, +, ?, grep, egrep, fgrep 8.

∑ Running process in background, Job control, and Process termination.

∑ Changing process priority, scheduling process (Usage of sleep and wait

9. Introduction to shell programming.

10. Shell control structures

11. Linux system administration

12. Linux Environment

RJS POLYTECHNIC, BANGALORE-34. Page 3

c) Your current working directory

number by ‘*’or ‘**’ respectively.

its validity and print an appropriate message.

RJS POLYTECHNIC, BANGALORE-34. Page 4

RJS POLYTECHNIC, BANGALORE-34. Page 5

Internal & External commands in Linux

2)CP (Copying a file)

To display the contents of the file

To append data to an existing file

[velumani@rjsplinux ~]$ cat -n fourth

[velumani@rjsplinux ~]$ date +%y

RJS POLYTECHNIC, BANGALORE-34. Page 16

Working with files & directories

Directory related commands

RJS POLYTECHNIC, BANGALORE-34. Page 17

File related commands

RJS POLYTECHNIC, BANGALORE-34. Page 18

2)Comparing two files

RJS POLYTECHNIC, BANGALORE-34. Page 19

5)Umask (User mask)

RJS POLYTECHNIC, BANGALORE-34. Page 20

RJS POLYTECHNIC, BANGALORE-34. Page 21

Manipulating file permission using chmod command

RJS POLYTECHNIC, BANGALORE-34. Page 22

2) Chown (change ownership)

RJS POLYTECHNIC, BANGALORE-34. Page 23

Manipulating Hardlink and Softlink using ln command

Softlink/Symbolic link/system link

Learn to use vi-editor

Once you issue a vi insert, append, or open command, you will be in vi

RJS POLYTECHNIC, BANGALORE-34. Page 25

Deleting and Cutting Blocks of Text

RJS POLYTECHNIC, BANGALORE-34. Page 26

Copying and Pasting Text