Discovering the concept of Linux

I am Teertha Darekar
Welcome back to my last day of workshop conducted by Pranav Jambare sir.

CONTENTS:-

Functions

Cases

Let's begin ;

--> Functions

Functions enable you to break down the overall functionality of a script into smaller, logical subsections, which can then be called upon to perform their individual tasks when needed.
Using functions to perform repetitive tasks is an excellent way to create code reuse.
It allows users to create shortcuts for lengthy tasks making the command-line experience more efficient and convenient.
The function name is used to call the function from elsewhere in your scripts.

Syntax:-

function_name () { 
   statement
}

Example:-

#!/bin/bash

just_echo() {
    echo " it's just a echo statement nothing else "
}

create_file () {
    echo " enter the file name "
    read name
    touch /tmp/${name}
}

just_echo
create_file

-->Case

The case statement simplifies complex conditions with multiple different choices.
This statement is easier to maintain and more readable than nested if statements.
The basic syntax of the case...esac statement is to give an expression to evaluate and to execute several different statements based on the value of the expression.

Syntax:-

case ${word} in
   1)
      Statements
      ;;
   2)
      Statements
      ;;
   3)
      Statements
      ;;
   *)
      Statements
     ;;
esac

Here the string word is compared against every pattern until a match is found.

The statements following the matching pattern execute.

If no matches are found, the case statement exits without performing any action.

When the statements part executes, the command ;; indicates that the program flow should jump to the end of the entire case statement.

() - used to run commands

{} - used to call value

Example 1:-

#!/bin/bash
echo " enter the colour "
read col
case ${col} in
1) 
    echo " It's a red colour "
;;
2)
    echo " It's a black clour "
;;
*)
    echo " It's an Invalid colour "
;;
esac

Example 2:-

#!/bin/bash
echo "1. file create "
echo "2. display file "
echo "3. current directory "
echo "4. make dir "
read input

case ${input} in
1)
   echo "enter the name of the file "
   read filename
   touch /tmp/${filename}
;;
2)
   echo " enter the name of the file "
   read filename
   ls -l /tmp/${filename}
;;
3)
   pwd
;;
4)
   echo " enter the name of dir "
   read dir
   mkdir /tmp/${dirname}
;;
*) 
   echo " Invalid Input "
;;
esac

Example 3:-

#!/bin/bash

function1()
{
   echo " function 1 is called "
}
function2()
{
   echo " function 2 is called "
}
function3()
{
   echo " function 3 is called "
}
function4()
{
   echo " function 4 is called "
}
function5()
{
   echo " function 5 is called "
}

echo " enter the function number to be called  "
read func
case ${func} in
1)
   function1
;;
2)
   function2
;;
3)
   function3
;;
4)
   function4
;;
5)
   function5
;;
*)
   echo " Invalid function "
;;
esac

And the last day of the workshop has been ended with a great experience and learning Linux.

Got to know about most of the concepts in Linux throughout the whole workshop.

Thank you ...

Discovering the concept of Linux

Linux workshop:- day 9

--> Functions

-->Case