BCA II Semester – Shell Programming Lab Manual & Viva Questions

Complete Guide for Lab + Viva Preparation

Introduction

Shell Programming is one of the most important subjects in BCA II Semester. It helps students automate tasks, manage files, and perform system-level operations efficiently.

• Complete Lab Manual Programs (Part A & Part B)
• Detailed Viva Questions with Answers
• Important Commands Table
• Simple explanations for exam preparation

What is Shell Programming?

Shell programming is writing commands in a script file that the shell executes. It acts as an interface between the user and operating system.

Key Features:

• Automation of tasks
• File handling
• Process management
• Loops and conditions

Basic Concepts

Shell

Command-line interpreter.

Shebang

#!/bin/bash

Variables

a=10
echo $a

Input/Output

read a
echo $a

PART A – Important Programs

1. Swap Two Numbers

read a b
temp=$a
a=$b
b=$temp
echo "$a $b"
    

2. Even or Odd

read n
if [ $((n%2)) -eq 0 ]
then echo "Even"
else echo "Odd"
fi
    

3. Largest of Three

read a b c
if [ $a -gt $b -a $a -gt $c ]
then echo $a
elif [ $b -gt $c ]
then echo $b
else echo $c
fi
    

4. Factorial

read n
fact=1
while [ $n -gt 1 ]
do
fact=$((fact*n))
n=$((n-1))
done
echo $fact
    

5. Fibonacci

read n
a=0 b=1
for ((i=0;i
  

PART B – Important Programs

1. Search Element

arr=(10 20 30 40)
read key
for i in "${arr[@]}"
do
if [ $i -eq $key ]
then echo "Found"
fi
done
    

2. Salary Calculation

read basic
hra=$((basic*20/100))
da=$((basic*10/100))
ta=$((basic*5/100))
total=$((basic+hra+da+ta))
echo $total
    

3. File Operations

mv old new
rm file
cp file1 file2
    

4. System Info

whoami
date
ps aux
echo $HOME
    

Important Viva Questions

• What is shell? Interface between user and OS
• Shell script? File of commands
• chmod? Change permissions
• Process? Program in execution
• fork()? Creates new process
• grep? Search command
• awk? Text processing tool
• Pipe (|)? Connect commands

Conclusion

Shell Programming is essential for system-level operations and automation. Practice programs and focus on logic for best results.

Bonus Tip

• Start with definition
• Explain logic
• Give example

Download PDF

Download Full Lab Manual PDF

© Yashavanth K | BCA Learning Blog