Basic Shell Scripting

Basic Shell Scripting

1. First Script

2. Run Basic Tasks

3. Run Basic Administration Tasks

4. Defining Variables

5. Input=Output

6. Conditional/If else statements

7. Case Statements

8. For loop script

9. do-while

10. Getting Online help

#!/bin/bash
# Author: Shounak Khulape
# Date Created: 02/23/2024
# Description:    This script will output "Hello World" on the screen
# Date Modified: 02/23/2024
echo
echo Hello World
echo

Basic Tasks Script

• Create 2nd script to run basic tasks

  • pwd

  • ls

  • whoami

  • date

  • cal

  • touch a b c

Basic Administration Tasks

• Create a script to run basic administration tasks

  • top

  • df -h

  • free -m

  • uptime

  • iostat

Defining Variables

• Create script to run basic tasks

  • p=pwd

  • l=ls

  • w=whoami

  • d=date

  • c='cal 2018'

Input/output

• Create script to take input from the user

  • read

  • echo

Conditional/If else statements

if-then statement

• If then statement

  • If this happens = do this

  • Otherwise = do that

Case Statement Scripts

• Case

  • If option a is selected = do this.

  • If option b is selected = do this.

  • If option c is selected = do this.

For Loop Scripts

• For Loops

  • Keep running until specified number of variable

  • eg: variable = 10 the run the script 10 times

  • variable = green, blue, red (then run the script 3 times for each color.)

#!/bin/bash
# Author: Shounak Khulape
# Date Created: 02/23/2023
# Description: This script will run basic admin command
# Date Modified: 02/23/2024
echo
echo This script will run basic administrative commands
echo
top
echo
df -h
echo
uptime
echo
iostat
echo
echo End of Script

#!/bin/bash
# Author: Shounak Khulape
# Date Created:    02/23/2024
# Description: Run Basic linux tasks
# Date Modified: 02/23/2024

echo
echo This script will run a few basic tasks
echo
pwd
ls
whoami
date
cal
touch a b c

#!/bin/bash
# Author: Shounak Khulape
# Date Created: 02/23/2024
# Description: This script is to check if a file error exit
# Date Modified: 02/23/2024
echo
clear
if [ -e /home/oracle/error.txt ]
then
    echo "File exist"
else
    echo "File does not exist"
fi

#!/bin/bash
# Date Created: 02/23/2024
# Author: Shounak Khulape
# Description: This script is regarding if-then command
# Date Modified: 02/23/2024

count=100
if [ $count -eq 100 ]
then
    echo Count is 100
else
    echo Count is not 100
fi

#!/bin/bash
# Author: Shounak Khulape
# Date Created: 02/23/2023
# Description: This script is created to dispaly input/output command.
# Date Modified: 02/23/2024
a=`hostname`
echo
echo Hello, my server name is $a
echo
echo Hello, My Name is Shounak Khulape
echo
echo What is your name?
read namecont
echo
echo Hello $namecont
echo

#!/bin/bash
# Date Created: 02/26/2024
# Author: Shounak Khulape
# Description: This script check the response and then output
# Date Modified: 02/26/2024
echo
clear
echo
echo "What is your name?"
echo
read a
echo

echo Hello $a sir
echo

echo "Do you like working in IT? (y/n)"
read like
echo

if [ "$like" == y ]
then
    echo You are cool
elif [ "$like" == n ]
then
    echo "You Should try IT, it's a good field"
echo
fi

#!/bin/bash
# Author: Shounak Khulape
# Date Created: 02/23/2024
# Description: This script is screated for declaring varaiable command
# Date Modified: 02/23/2024
echo
# Define Variables
p=pwd
l=ls
wi=whoami
d=date
c="cal 2018"

echo Run variables tasks
echo
$p
$l
$wi
$d
$c

That's great if you have make till here you have covered Basic Shell Standards.

If you liked what you read, do follow and any feedback for further improvement will be highly appreciated!

Thank you and Happy Learning!👏