<?xml version="1.0"?>
<?xml-stylesheet type="text/css" href="https://script.spoken-tutorial.org/skins/common/feed.css?303"?>
<feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en">
		<id>https://script.spoken-tutorial.org/index.php?action=history&amp;feed=atom&amp;title=BASH%2FC2%2FConditional-Loops%2FEnglish</id>
		<title>BASH/C2/Conditional-Loops/English - Revision history</title>
		<link rel="self" type="application/atom+xml" href="https://script.spoken-tutorial.org/index.php?action=history&amp;feed=atom&amp;title=BASH%2FC2%2FConditional-Loops%2FEnglish"/>
		<link rel="alternate" type="text/html" href="https://script.spoken-tutorial.org/index.php?title=BASH/C2/Conditional-Loops/English&amp;action=history"/>
		<updated>2026-05-13T18:34:14Z</updated>
		<subtitle>Revision history for this page on the wiki</subtitle>
		<generator>MediaWiki 1.23.17</generator>

	<entry>
		<id>https://script.spoken-tutorial.org/index.php?title=BASH/C2/Conditional-Loops/English&amp;diff=8136&amp;oldid=prev</id>
		<title>Nancyvarkey at 06:03, 7 January 2014</title>
		<link rel="alternate" type="text/html" href="https://script.spoken-tutorial.org/index.php?title=BASH/C2/Conditional-Loops/English&amp;diff=8136&amp;oldid=prev"/>
				<updated>2014-01-07T06:03:48Z</updated>
		
		<summary type="html">&lt;p&gt;&lt;/p&gt;
&lt;a href=&quot;https://script.spoken-tutorial.org/index.php?title=BASH/C2/Conditional-Loops/English&amp;amp;diff=8136&amp;amp;oldid=8068&quot;&gt;Show changes&lt;/a&gt;</summary>
		<author><name>Nancyvarkey</name></author>	</entry>

	<entry>
		<id>https://script.spoken-tutorial.org/index.php?title=BASH/C2/Conditional-Loops/English&amp;diff=8068&amp;oldid=prev</id>
		<title>Ashwini: Created page with ''''Title of script:''' '''Basic If loop in BASH '''  '''Author:''' Ashwini Patil  '''Keywords: video tutorial, for loop, while loop'''    {| style=&quot;border-spacing:0;&quot; ! &lt;center&gt;V…'</title>
		<link rel="alternate" type="text/html" href="https://script.spoken-tutorial.org/index.php?title=BASH/C2/Conditional-Loops/English&amp;diff=8068&amp;oldid=prev"/>
				<updated>2013-12-30T10:22:54Z</updated>
		
		<summary type="html">&lt;p&gt;Created page with &amp;#039;&amp;#039;&amp;#039;&amp;#039;Title of script:&amp;#039;&amp;#039;&amp;#039; &amp;#039;&amp;#039;&amp;#039;Basic If loop in BASH &amp;#039;&amp;#039;&amp;#039;  &amp;#039;&amp;#039;&amp;#039;Author:&amp;#039;&amp;#039;&amp;#039; Ashwini Patil  &amp;#039;&amp;#039;&amp;#039;Keywords: video tutorial, for loop, while loop&amp;#039;&amp;#039;&amp;#039;    {| style=&amp;quot;border-spacing:0;&amp;quot; ! &amp;lt;center&amp;gt;V…&amp;#039;&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;'''Title of script:''' '''Basic If loop in BASH '''&lt;br /&gt;
&lt;br /&gt;
'''Author:''' Ashwini Patil&lt;br /&gt;
&lt;br /&gt;
'''Keywords: video tutorial, for loop, while loop'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
{| style=&amp;quot;border-spacing:0;&amp;quot;&lt;br /&gt;
! &amp;lt;center&amp;gt;Visual Cue&amp;lt;/center&amp;gt;&lt;br /&gt;
! &amp;lt;center&amp;gt;Narration&amp;lt;/center&amp;gt;&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 1&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Dear friends, welcome to the spoken tutorial on &lt;br /&gt;
&lt;br /&gt;
'''loops '''in '''BASH'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 2&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| In this tutorial, we will learn&lt;br /&gt;
&lt;br /&gt;
* '''for loop''' and&lt;br /&gt;
* '''while loop'''&amp;lt;br/&amp;gt; with a few examples&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 3&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| For this tutorial I am using''' '''&lt;br /&gt;
&lt;br /&gt;
* '''Ubuntu Linux''' 12.04 '''Operating System '''&lt;br /&gt;
* and '''GNU BASH''' version 4.1.10&lt;br /&gt;
&lt;br /&gt;
Please note,''' GNU bash''' version 4 or above is recommended to practice this tutorial.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 4&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us start with an introduction to''' loops'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
'''Loops''' are used to execute a group of statements repeatedly.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 5&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us start with '''for''' '''loop'''.&lt;br /&gt;
&lt;br /&gt;
Syntax of '''for loop''' is as follows: &lt;br /&gt;
&lt;br /&gt;
'''for ((exp1; exp2; exp3))'''&lt;br /&gt;
&lt;br /&gt;
'''do'''&lt;br /&gt;
&lt;br /&gt;
'''statement1'''&lt;br /&gt;
&lt;br /&gt;
'''statement2'''&lt;br /&gt;
&lt;br /&gt;
'''statement3'''&lt;br /&gt;
&lt;br /&gt;
'''done'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide &lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| An alternate syntax of '''for loop '''is:&lt;br /&gt;
&lt;br /&gt;
'''for variable in sequence/range'''&lt;br /&gt;
&lt;br /&gt;
'''do'''&lt;br /&gt;
&lt;br /&gt;
'''statement1'''&lt;br /&gt;
&lt;br /&gt;
'''statement2'''&lt;br /&gt;
&lt;br /&gt;
'''statement3'''&lt;br /&gt;
&lt;br /&gt;
'''done'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Switch to the program in '''gedit'''.&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us see an example of '''for loop '''using the 1st syntax.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
In this program, we will calculate the sum of''' '''the first '''n''' numbers.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Point cursor to the filename '''for.sh'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Note that our filename is''' for.sh'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''&amp;lt;nowiki&amp;gt;#!/bin/bash &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| This is our '''shebang line'''.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''read -p “Enter number: ” y'''&lt;br /&gt;
&lt;br /&gt;
'''sum=0 '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| The variable y will store the value given by user. The value is an integer here.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
Now, we initialize the variable '''sum''' as '''0.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;for ((i=1;i&amp;lt;=y;&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
&lt;br /&gt;
Do not highlight&lt;br /&gt;
&lt;br /&gt;
'''i++))'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| This is where we begin the '''for loop.'''&lt;br /&gt;
&lt;br /&gt;
First, we initialize '''i''' to the value '''1'''.&lt;br /&gt;
&lt;br /&gt;
Then we check whether '''i''' is less than or equal to '''y'''.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight &lt;br /&gt;
&lt;br /&gt;
'''do'''&lt;br /&gt;
&lt;br /&gt;
'''echo $((sum=sum+i)) '''&lt;br /&gt;
&lt;br /&gt;
'''done '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Now here, we calculate the '''sum '''as '''sum plus i'''&lt;br /&gt;
&lt;br /&gt;
and then we print it.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''i++))'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| After this, we increment the value of '''i '''by 1'''.'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''&amp;lt;nowiki&amp;gt;i&amp;lt;=y;&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| And then we check the same condition till this condition is false .&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''echo &amp;quot;Sum of first n numbers is $sum&amp;quot;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| On exiting the '''for loop, '''this message is printed.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| &lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us execute the program and observe what happens.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Switch to the terminal and type:&lt;br /&gt;
&lt;br /&gt;
'''chmod +x for.sh'''&lt;br /&gt;
&lt;br /&gt;
Type:&lt;br /&gt;
&lt;br /&gt;
'''./for.sh'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| On the '''terminal''' type -&lt;br /&gt;
&lt;br /&gt;
'''chmod +x for.sh'''&lt;br /&gt;
&lt;br /&gt;
Then type:&lt;br /&gt;
&lt;br /&gt;
'''./for.sh'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Type: '''5'''&lt;br /&gt;
&lt;br /&gt;
Highlight the output&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| I will enter '''5 '''as the input number.&lt;br /&gt;
&lt;br /&gt;
The '''sum '''that is calculated for each value of '''i '''is displayed.&lt;br /&gt;
&lt;br /&gt;
After that, the last line of the output is displayed:&lt;br /&gt;
&lt;br /&gt;
'''Sum of first 5 numbers is''' '''15'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Resize the terminal window and the editor.&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Now let us see the flow of the program.&lt;br /&gt;
&lt;br /&gt;
Let me resize the window.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''for ((i=1;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| First we have value of''' i '''as''' 1.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''&amp;lt;nowiki&amp;gt;i&amp;lt;=y;&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Then we check whether''' 1 '''is less than or equal to''' 5.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight &lt;br /&gt;
&lt;br /&gt;
'''do'''&lt;br /&gt;
&lt;br /&gt;
'''echo $((sum=sum+i)) '''&lt;br /&gt;
&lt;br /&gt;
'''done '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Since the condition is '''true,''' we calculate '''sum '''as''' 0 + 1.'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
Now we have '''sum '''as '''1.'''&lt;br /&gt;
&lt;br /&gt;
Then we print '''sum '''i.e '''1.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''i++))'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Next, '''i '''is incremented by '''1''' and the new value of''' i '''is''' 2.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''3''' in the output&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Then we check whether''' 2 '''is less than or equal to''' 5.'''&lt;br /&gt;
&lt;br /&gt;
The condition is '''true '''and now sum will be''' 1+2 '''ie''' 3.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''i++))'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| '''i '''is then incremented by '''1''' and the new value of''' i i'''s''' 3.'''&lt;br /&gt;
&lt;br /&gt;
And we get '''sum '''as''' 6.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| &lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| The script will continue to add the next value of '''i '''to the previous value in''' sum.'''&lt;br /&gt;
&lt;br /&gt;
This will continue till '''&amp;lt;nowiki&amp;gt;i&amp;lt;=5&amp;lt;/nowiki&amp;gt; is false.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''echo &amp;quot;Sum of first n numbers is $sum&amp;quot;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| On exiting the '''for loop, '''the final message is printed.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;&amp;lt;PAUSE&amp;gt;&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Open file '''for-loop.sh''' &amp;gt;&amp;gt; Point cursor to the filename.&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us see another example of '''for loop '''using the 2nd syntax.&lt;br /&gt;
&lt;br /&gt;
I have written the code in this file and named it as '''for-loop.sh'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
This simple program will list the files in a directory.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight '''&amp;lt;nowiki&amp;gt;#!/bin/bash&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| This is the '''shebang line.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''for file in $(ls -1); '''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Then we have '''for loop'''.&lt;br /&gt;
&lt;br /&gt;
'''ls''' command lists the directory content.&lt;br /&gt;
&lt;br /&gt;
'''-1''' lists one file per line.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''do '''&lt;br /&gt;
&lt;br /&gt;
'''echo $file; '''&lt;br /&gt;
&lt;br /&gt;
'''done'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| This will list all the files present in your home directory.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
This is the end of '''for loop.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| On the terminal, type&lt;br /&gt;
&lt;br /&gt;
'''chmod +x for-loop.sh'''&lt;br /&gt;
&lt;br /&gt;
'''./for-loop.sh'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us execute the script on the terminal by typing - &lt;br /&gt;
&lt;br /&gt;
'''chmod +x for-loop.sh'''&lt;br /&gt;
&lt;br /&gt;
'''./for-loop.sh'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Show the output&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| This will display all the files present in the home directory.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Switch to the slides&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Now, we will learn about the''' while loop.'''&lt;br /&gt;
&lt;br /&gt;
Let us understand the syntax first.&lt;br /&gt;
&lt;br /&gt;
I will switch back to the slides&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 6&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Syntax:&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;while [ condition ]&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
&lt;br /&gt;
'''do'''&lt;br /&gt;
&lt;br /&gt;
'''statement1'''&lt;br /&gt;
&lt;br /&gt;
'''statement2'''&lt;br /&gt;
&lt;br /&gt;
'''statement3'''&lt;br /&gt;
&lt;br /&gt;
'''done'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
This means that the '''while loop''' will execute as long as the condition is '''true.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Point cursor to the filename&lt;br /&gt;
&lt;br /&gt;
'''while.sh'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us see an example of''' while loop.'''&lt;br /&gt;
&lt;br /&gt;
I have the program here and I have named it as '''while.sh'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
In this program, we will calculate the sum of even numbers within a given range.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''read -p “Enter number:” num'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us go through the code.&lt;br /&gt;
&lt;br /&gt;
Here, we accept a number from the user and store it in variable '''num'''.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''i=0 '''&lt;br /&gt;
&lt;br /&gt;
'''sum=0'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Next, we declare variables '''i''' &amp;amp; '''sum''' and initialize them to''' 0.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight'''&amp;lt;nowiki&amp;gt;while [ $i -le $num ] &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
&lt;br /&gt;
'''do'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Now this is the''' while condition.'''&lt;br /&gt;
&lt;br /&gt;
Here we check whether '''i''' is '''less than or equal''' to value of '''num '''given by the user.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''echo $((sum=sum+i)) '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Then we calculate the '''sum by adding value of i to value of sum'''.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;i=$[$i+2] &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
&lt;br /&gt;
'''done '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Next, we increment the value of '''i''' with '''2'''.&lt;br /&gt;
&lt;br /&gt;
This will ensure that we only add the even numbers .&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
And the while loop is repeated till the value of '''i''' exceeds the value of '''num.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| '''echo &amp;quot;Sum of even numbers within the given range is $sum&amp;quot; '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| When we exit the '''while loop, '''we print the sum of all the even numbers within the given range.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| On the terminal&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let us execute the program.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Type:&lt;br /&gt;
&lt;br /&gt;
chmod +x while.sh&lt;br /&gt;
&lt;br /&gt;
Type:&lt;br /&gt;
&lt;br /&gt;
./while.sh&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Type:&lt;br /&gt;
&lt;br /&gt;
'''chmod +x while.sh'''&lt;br /&gt;
&lt;br /&gt;
Type:&lt;br /&gt;
&lt;br /&gt;
'''./while.sh'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Type: 15&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| I will give '''15 '''as my input.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight the output&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| The last line of the output is:&lt;br /&gt;
&lt;br /&gt;
'''Sum of even numbers within the given range is 56.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Resize the editor window and the terminal&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Let me resize the window and explain the output.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight'''&amp;lt;nowiki&amp;gt;while [ $i -le $num ] &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| First we check whether '''i''' which is '''0,''' is less than or equal to '''num''', which is '''15'''.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''$((sum=sum+i)) '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| The condition is '''true, '''hence '''sum '''will be '''0+0 '''ie '''0.'''&lt;br /&gt;
&lt;br /&gt;
And we print '''0.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;i=$[$i+2] &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Now '''i''' will be incremented by '''2 '''and the '''new '''value of''' i '''is''' 2.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight'''&amp;lt;nowiki&amp;gt;while [ $i -le $num ] &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Then we check if '''2''' is less than or equal to '''15'''.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''$((sum=sum+i)) '''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| The condition is again '''true; '''so we add '''0+2.'''&lt;br /&gt;
&lt;br /&gt;
Now '''sum '''has the value '''2.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;i=$[$i+2] &amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| And the value of '''i''' will be incremented by '''2'''.&lt;br /&gt;
&lt;br /&gt;
So now value of '''i''' will be '''2+2''' ie '''4.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Highlight the output&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| And the next value of''' sum '''will be '''4+2 '''ie '''6.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| &lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| In the same way, the script will continue to add '''2''' to the previous value of '''i, '''till it exceeds '''15'''.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
And we get the total value in '''sum '''as''' 56.'''&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
'''&amp;lt;nowiki&amp;gt;&amp;lt;PAUSE&amp;gt;&amp;lt;/nowiki&amp;gt;'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 8&lt;br /&gt;
&lt;br /&gt;
Summary&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Summary&lt;br /&gt;
&lt;br /&gt;
In this tutorial we learnt 2 different syntax of '''for loop '''and we also learnt about the '''while loop.'''&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 9&lt;br /&gt;
&lt;br /&gt;
Assignment&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| As an assignment -&lt;br /&gt;
&lt;br /&gt;
Find the sum of the first n prime numbers.&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 10&lt;br /&gt;
&lt;br /&gt;
http://spoken-tutorial.org /What\_is\_a\_Spoken\_Tutorial&lt;br /&gt;
&lt;br /&gt;
About the Spoken Tutorial Project&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Watch the video available at the link shown below&lt;br /&gt;
&lt;br /&gt;
It summarises the Spoken Tutorial project &lt;br /&gt;
&lt;br /&gt;
If you do not have good bandwidth, you can download and watch it&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 11&lt;br /&gt;
&lt;br /&gt;
Spoken Tutorial Workshops&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| The Spoken Tutorial Project Team &lt;br /&gt;
&lt;br /&gt;
Conducts workshops using spoken tutorials &lt;br /&gt;
&lt;br /&gt;
Gives certificates to those who pass an online test &lt;br /&gt;
&lt;br /&gt;
For more details, please write to&lt;br /&gt;
&lt;br /&gt;
contact@spoken-tutorial.org&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| Display Slide 12&lt;br /&gt;
&lt;br /&gt;
Acknowledgement&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| Spoken Tutorial Project is a part of the Talk to a Teacher project&lt;br /&gt;
&lt;br /&gt;
It is supported by the National Mission on Education through ICT, MHRD, Government of India&lt;br /&gt;
&lt;br /&gt;
More information on this Mission is available at: http://spoken-tutorial.org\NMEICT-Intro&lt;br /&gt;
&lt;br /&gt;
|-&lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:none;padding:0.097cm;&amp;quot;| &lt;br /&gt;
| style=&amp;quot;border-top:none;border-bottom:1pt solid #000000;border-left:1pt solid #000000;border-right:1pt solid #000000;padding:0.097cm;&amp;quot;| This is Ashwini Patil from IIT Bombay&lt;br /&gt;
&lt;br /&gt;
Thank You for joining.&lt;br /&gt;
&lt;br /&gt;
|}&lt;/div&gt;</summary>
		<author><name>Ashwini</name></author>	</entry>

	</feed>