Difference between revisions of "BASH/C3/Arrays-and-functions/English-timed"

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(Created page with "{| border=1 |'''Time''' |'''Narration''' |- | 00:01 | Dear friends, Welcome to the spoken tutorial on '''Arrays & functions''' |- | 00:07 | In this tutorial, we will learn...")
 
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|-
 
|-
 
| 00:01
 
| 00:01
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| Dear friends, Welcome to the spoken tutorial on '''Arrays & functions'''
+
| Dear friends, Welcome to the spoken tutorial on '''Arrays & functions'''.
  
 
|-
 
|-
 
| 00:07
 
| 00:07
−
| In this tutorial, we will learn
+
| In this tutorial, we will learn:
  
 
|-
 
|-
 
|00:11
 
|00:11
−
| To pass an '''array''' to a''' function '''
+
|* To pass an '''array''' to a''' function '''
  
 
|-
 
|-
 
|00:14
 
|00:14
−
|Use of''' exit '''statement in a '''function'''
+
|* Use of''' exit '''statement in a '''function'''
  
 
|-
 
|-
 
|00:17
 
|00:17
−
| Use of '''return''' statement in a '''function'''
+
|* Use of '''return''' statement in a '''function'''
  
 
|-
 
|-
 
|00:20
 
|00:20
−
| With the help of some examples  
+
| with the help of some examples.
  
 
|-
 
|-
 
| 00:24
 
| 00:24
−
| To follow this tutorial you should have knowledge of '''Shell Scripting.'''
+
| To follow this tutorial, you should have knowledge of '''Shell Scripting.'''
  
 
|-
 
|-
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|-
 
|-
 
|00:36
 
|00:36
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|If not, for relevant tutorials please visit our website which is as shown,'''http://www.spoken-tutorial.org'''
+
|If not, for relevant tutorials, please visit our website which is as shown. '''http://www.spoken-tutorial.org'''
  
 
|-
 
|-
 
| 00:43
 
| 00:43
−
| For this tutorial I am using''' '''
+
| For this tutorial, I am using:
  
 
|-
 
|-
 
|00:46
 
|00:46
−
| '''Ubuntu Linux''' 12.04''' '''Operating System and
+
|* '''Ubuntu Linux''' 12.04''' '''Operating System and
  
 
|-
 
|-
 
|00:50
 
|00:50
−
| '''GNU BASH''' version 4.2
+
|* '''GNU BASH''' version 4.2
  
 
|-
 
|-
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|-  
 
|-  
 
|01:02
 
|01:02
−
| Let us first learn how to pass an '''array''' to a '''function,''' and its usage.
+
| Let us first learn how to pass an '''array''' to a '''function''' and its usage.
  
 
|-
 
|-
 
| 01:09
 
| 01:09
−
| Let me open a file '''function_(underscore)array dot sh'''
+
| Let me open a file '''function_(underscore)array dot sh'''.
  
 
|-  
 
|-  
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|-  
 
|-  
 
|01:18
 
|01:18
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| Our '''function''' name is '''array_(underscore) display'''
+
| Our '''function''' name is '''array_(underscore) display'''.
  
 
|-
 
|-
 
|01:22
 
|01:22
−
|Open curly brace opens the '''function definition.'''
+
|Open curly brace opens the '''function''' definition.
  
 
|-  
 
|-  
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|-
 
|-
 
|01:40
 
|01:40
−
|'''Dollar @ (at sign) within round brackets '''stores '''array elements '''in variable ''''array'.'''
+
|'''Dollar @''' (at sign) within round brackets stores '''array elements '''in variable ''''array'.'''
  
 
|-  
 
|-  
 
|01:47
 
|01:47
−
| '''Dollar''' opening curly brace '''array''' within square bracket @(At-sign) closing curly brace
+
| '''Dollar''' opening curly brace '''array''' within square bracket @(At-sign) closing curly brace.
  
 
|-
 
|-
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|-  
 
|-  
 
|02:00
 
|02:00
−
| '''Dollar''' opening curly brace array within square bracket one closing curly brace
+
| '''Dollar''' opening curly brace '''array''' within square bracket one closing curly brace
  
 
|-
 
|-
 
|02:08
 
|02:08
−
|This line of code displays the second '''element''' of the '''array'''
+
|This line of code displays the second '''element''' of the '''array'''.
  
 
|-
 
|-
 
| 02:14
 
| 02:14
−
|  '''Operating_systems '''is declared with the elements '''Ubuntu, Fedora, Redhat '''and''' Suse'''
+
|  '''Operating_systems '''is declared with the elements '''Ubuntu, Fedora, Redhat '''and''' Suse'''.
  
 
|-
 
|-
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|-
 
|-
 
|02:29
 
|02:29
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| The syntax to pass an '''array''' to a '''function''' is '''function_name''' space '''dollar''' opening curly brace '''array_name''' within square bracket '''@(At sign)''' closing curly brace
+
| The syntax to pass an '''array''' to a '''function''' is '''function_name''' space '''dollar''' opening curly brace '''array_name''' within square brackets '''@(At sign)''' closing curly brace.
  
 
|-
 
|-
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|-  
 
|-  
 
|02:48
 
|02:48
−
| Similarly, '''colors''' is declared with the '''elements''' '''White, green, red '''and''' blue'''
+
| Similarly, '''colors''' is declared with the '''elements''' '''White, green, red '''and''' blue'''.
  
 
|-
 
|-
 
|02:57
 
|02:57
−
|Here, '''array colors''' is passed to the '''function''' '''array_display'''
+
|Here, '''array colors''' is passed to the '''function''' '''array_display'''.
  
 
|-  
 
|-  
 
|03:02
 
|03:02
−
| Now let's save the file and go to the '''terminal'''.
+
| Now let's '''save''' the file and go to the '''terminal'''.
  
 
|-  
 
|-  
 
|03:07
 
|03:07
−
| Type '''chmod space plus x space function underscore array dot sh'''
+
| Type: '''chmod space plus x space function underscore array dot sh'''
  
 
|-
 
|-
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|-  
 
|-  
 
|03:19
 
|03:19
−
| Type '''dot slash function underscore array dot sh'''
+
| Type: '''dot slash function underscore array dot sh'''
  
 
|-
 
|-
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|-
 
|-
 
|03:33
 
|03:33
−
|And the '''second array element''' of ''''operating_systems'''' and ''''colors'''' are also displayed.
+
|And the second '''array element''' of ''''operating_systems'''' and ''''colors'''' are also displayed.
  
 
|-  
 
|-  
 
|03:41
 
|03:41
−
| In '''Bash''', ''''exit' '''and''' 'return' statements '''gives status code of a '''function''' or a program.
+
| In '''Bash''', ''' 'exit' '''and''' 'return' statements '''give '''status code''' of a '''function''' or a program.
  
 
|-  
 
|-  
 
| 03:49
 
| 03:49
−
|The '''return''' statement will return to the script from where it was called.
+
|The '''return''' statement will return to the '''script''' from where it was called.
  
 
|-
 
|-
 
|03:54
 
|03:54
−
|'''exit '''statement will end the entire script from where it is encountered.
+
|'''exit '''statement will end the entire '''script''' from where it is encountered.
  
 
|-
 
|-
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|-  
 
|-  
 
|04:06
 
|04:06
−
| Let me open a file ''''return_exit.sh''''
+
| Let me open a file ''''return_exit.sh''''.
  
 
|-  
 
|-  
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|-
 
|-
 
| 04:14
 
| 04:14
−
| Function name is '''return_(Underscore)function '''
+
| Function name is '''return_(Underscore)function '''.
  
 
|-
 
|-
 
| 04:18
 
| 04:18
−
| Open curly brace opens the '''function definition.'''
+
| Open curly brace opens the '''function''' definition.
  
 
|-  
 
|-  
 
|04:22
 
|04:22
−
| This '''if statement '''compares two variables.
+
| This '''if statement '''compares two '''variables'''.
  
 
|-
 
|-
 
|04:27
 
|04:27
−
|If the two variables are equal, then commands in ''''if'''' are executed.
+
|If the two variables are equal then '''commands''' in ''''if'''' are executed.
  
 
|-
 
|-
 
|04:33
 
|04:33
−
| This '''echo statement '''displays the message
+
| This '''echo statement '''displays the message:
  
 
|-
 
|-
 
|04:36
 
|04:36
−
|'''This is return function.'''
+
|'''"This is return function".'''
  
 
|-  
 
|-  
 
|04:39
 
|04:39
−
| '''return 0 '''moves the control from '''function''' to main program with status code 0(zero).
+
| '''return 0 '''moves the control from '''function''' to '''main''' program with status code 0(zero).
  
 
|-  
 
|-  
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|-
 
|-
 
| 04:54
 
| 04:54
−
| '''fi''' indicates the end of '''if statement'''
+
| '''fi''' indicates the end of '''if statement'''.
  
 
|-  
 
|-  
 
|04:58
 
|04:58
−
| Here the '''function '''name is''' exit_(Undescore)function '''
+
| Here the '''function '''name is''' exit_(Undescore)function '''.
  
 
|-  
 
|-  
 
|05:02
 
|05:02
−
| The '''if statement '''here compares two variables.
+
| The '''if statement '''here compares two '''variables'''.
  
 
|-  
 
|-  
 
|05:06
 
|05:06
−
| If the two variables are equal, then the commands in ''''if'''' are executed.
+
| If the two variables are equal then the '''commands''' in ''''if'''' are executed.
  
 
|-
 
|-
 
| 05:14
 
| 05:14
−
| This '''echo statement '''displays the message '''"This is exit function"'''
+
| This '''echo statement '''displays the message '''"This is exit function" '''.
  
 
|-
 
|-
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|-  
 
|-  
 
|05:33
 
|05:33
−
| This displays the message '''"We are in main program"'''
+
| This displays the message '''"We are in main program"'''.
  
 
|-  
 
|-  
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|-  
 
|-  
 
|05:44
 
|05:44
−
| This '''echo statement '''displays the message '''"This line is not displayed"'''
+
| This '''echo statement '''displays the message '''"This line is not displayed"'''.
  
 
|-
 
|-
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|-
 
|-
 
|05:58
 
|05:58
−
| Save the file and go to the '''terminal.'''
+
| '''Save''' the file and go to the '''terminal.'''
  
 
|-
 
|-
 
|06:00
 
|06:00
−
| Type '''chmod space plus x space return underscore exit dot sh'''
+
| Type: '''chmod space plus x space return underscore exit dot sh'''
  
 
|-  
 
|-  
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|-
 
|-
 
| 06:12
 
| 06:12
−
|Type '''dot slash return underscore exit dot sh'''
+
|Type: '''dot slash return underscore exit dot sh'''
  
 
|-  
 
|-  
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|-
 
|-
 
| 06:20
 
| 06:20
−
| The output displays the messages as shown.
+
| The '''output''' displays the messages as shown.
  
 
|-
 
|-
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|-  
 
|-  
 
| 06:27
 
| 06:27
−
|The control will be in main program, which is the script itself.
+
|The '''control''' will be in '''main''' program which is the '''script''' itself.
  
 
|-
 
|-
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|-
 
|-
 
| 06:39
 
| 06:39
−
| As the two variables are equal, it displays the message '"This is return function'''
+
| As the two '''variables''' are equal, it displays the message '"This is return function'''.
  
 
|-
 
|-
 
| 06:47
 
| 06:47
−
| Then it encounters '''return 0.'''And the control flows from '''function''' to the statement below the '''function call, '''in the main program.
+
| Then it encounters '''return 0.''' And the control flows from '''function''' to the '''statement''' below the '''function call,''' in the '''main program'''.
  
 
|-
 
|-
 
| 06:59
 
| 06:59
−
| Then it displays the message '''We are in main program'''
+
| Then it displays the message''' "We are in main program" '''.
  
 
|-
 
|-
 
| 07:03
 
| 07:03
−
| After that, the control goes to '''exit_function''' because of the '''function call'''.
+
| After that, the '''control''' goes to '''exit_function''' because of the '''function call'''.
  
 
|-
 
|-
 
| 07:11
 
| 07:11
−
|As the two variables are equal, it displays the message '''"This is exit function"'''
+
|As the two variables are equal, it displays the message '''"This is exit function".'''
  
 
|-
 
|-
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|-
 
|-
 
| 07:39
 
| 07:39
−
|Let us now summarise.
+
|Let us now summarize.
  
 
|-
 
|-
 
| 07:41
 
| 07:41
−
| In this tutorial, we learnt
+
| In this tutorial, we learnt:
  
 
|-
 
|-
 
| 07:44
 
| 07:44
−
|To pass an '''array''' to a '''function '''
+
|* To pass an '''array''' to a '''function '''
  
 
|-
 
|-
 
| 07:47
 
| 07:47
−
| Use of''' exit''' statement in a '''function'''
+
|* Use of''' exit''' statement in a '''function'''
  
 
|-
 
|-
 
| 07:50
 
| 07:50
−
| Use of '''return''' statement in a '''function'''
+
|* Use of '''return''' statement in a '''function'''
  
 
|-
 
|-
 
|07:53  
 
|07:53  
−
|With the help of some examples  
+
|with the help of some examples.
  
 
|-
 
|-
 
| 07:56
 
| 07:56
−
| As an assignment.
+
| As an assignment-
  
 
|-
 
|-
 
| 07:57
 
| 07:57
−
|Write a program,
+
|Write a program  
  
 
|-
 
|-
 
| 07:58
 
| 07:58
−
|  Where a '''function '''adds all the elements in an '''array'''  The '''function''' should display the sum of elements.
+
|  where a '''function '''adds all the '''elements''' in an '''array'''. The '''function''' should display the sum of elements.
  
 
|-
 
|-
 
| 08:07
 
| 08:07
−
|Make 2 '''function''' '''calls''' with '''array elements''' (1, 2, 3) and (4, 5, 6)
+
|Make 2 '''function''' '''calls''' with '''array elements''' (1, 2, 3) and (4, 5, 6).
  
 
|-  
 
|-  
 
|08:15
 
|08:15
−
| Watch the video available at the link shown below. http://spoken-tutorial.org /What\_is\_a\_Spoken\_Tutorial
+
| Watch the video available at the link shown below. http://spoken-tutorial.org /What_is_a_Spoken_Tutorial.
  
 
|-
 
|-
 
| 08:19
 
| 08:19
−
|It summarises the Spoken Tutorial project.
+
|It summarizes the Spoken Tutorial project.
  
 
|-
 
|-
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|-  
 
|-  
 
|08:28
 
|08:28
−
| The Spoken Tutorial Project Team
+
| The Spoken Tutorial Project Team:
  
 
|-
 
|-
 
| 08:30
 
| 08:30
−
| Conducts workshops using spoken tutorials Gives certificates to those who pass an online test For more details, please write to contact@spoken-tutorial.org
+
| Conducts workshops using spoken tutorials.
 +
Gives certificates to those who pass an online test.
 +
For more details, please write to contact@spoken-tutorial.org
  
 
|-  
 
|-  
 
|08:45
 
|08:45
−
| Spoken Tutorial Project is a part of the Talk to a Teacher project.
+
| '''Spoken Tutorial''' Project is a part of the '''Talk to a Teacher''' project.
  
 
|-
 
|-
 
| 08:49
 
| 08:49
−
|It is supported by the National Mission on Education through ICT, MHRD, Government of India.More information on this Mission is available at the link shown below http://spoken-tutorial.org\NMEICT-Intro
+
|It is supported by the National Mission on Education through ICT, MHRD, Government of India. More information on this mission is available at the link shown below. http://spoken-tutorial.org\NMEICT-Intro
  
 
|-
 
|-
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|-
 
|-
 
| 09:10
 
| 09:10
−
|This is Ashwini Patil from IIT Bombay signing off. Thank you for joining.
+
|This is Ashwini Patil from IIT Bombay, signing off. Thank you for joining.
  
 
|}
 
|}

Revision as of 14:18, 6 July 2015

Time Narration
00:01 Dear friends, Welcome to the spoken tutorial on Arrays & functions.
00:07 In this tutorial, we will learn:
00:11 * To pass an array to a function
00:14 * Use of exit statement in a function
00:17 * Use of return statement in a function
00:20 with the help of some examples.
00:24 To follow this tutorial, you should have knowledge of Shell Scripting.
00:29 You should also have knowledge of arrays and if statement in BASH.
00:36 If not, for relevant tutorials, please visit our website which is as shown. http://www.spoken-tutorial.org
00:43 For this tutorial, I am using:
00:46 * Ubuntu Linux 12.04 Operating System and
00:50 * GNU BASH version 4.2
00:54 Please note, GNU Bash version 4 or above is recommended to practice this tutorial.
01:02 Let us first learn how to pass an array to a function and its usage.
01:09 Let me open a file function_(underscore)array dot sh.
01:15 This is the shebang line.
01:18 Our function name is array_(underscore) display.
01:22 Open curly brace opens the function definition.
01:27 The use of Dollar @(at-sign) was explained in previous tutorials in this series.
01:34 Basically, it is used to print all arguments passed to a function.
01:40 Dollar @ (at sign) within round brackets stores array elements in variable 'array'.
01:47 Dollar opening curly brace array within square bracket @(At-sign) closing curly brace.
01:55 This line of code displays all the elements of an array.
02:00 Dollar opening curly brace array within square bracket one closing curly brace
02:08 This line of code displays the second element of the array.
02:14 Operating_systems is declared with the elements Ubuntu, Fedora, Redhat and Suse.
02:22 Here, array operating_systems is passed to the function array_display'.
02:29 The syntax to pass an array to a function is function_name space dollar opening curly brace array_name within square brackets @(At sign) closing curly brace.
02:45 Come back to our program.
02:48 Similarly, colors is declared with the elements White, green, red and blue.
02:57 Here, array colors is passed to the function array_display.
03:02 Now let's save the file and go to the terminal.
03:07 Type: chmod space plus x space function underscore array dot sh
03:18 Press Enter.
03:19 Type: dot slash function underscore array dot sh
03:25 Press Enter.
03:27 As we can see, array elements of 'operating_systems' and 'colors' are displayed.
03:33 And the second array element of 'operating_systems' and 'colors' are also displayed.
03:41 In Bash, 'exit' and 'return' statements give status code of a function or a program.
03:49 The return statement will return to the script from where it was called.
03:54 exit statement will end the entire script from where it is encountered.
04:01 Let us learn these 2 ways to return within a function.
04:06 Let me open a file 'return_exit.sh'.
04:12 This is the shebang line.
04:14 Function name is return_(Underscore)function .
04:18 Open curly brace opens the function definition.
04:22 This if statement compares two variables.
04:27 If the two variables are equal then commands in 'if' are executed.
04:33 This echo statement displays the message:
04:36 "This is return function".
04:39 return 0 moves the control from function to main program with status code 0(zero).
04:47 Note that the statements after return will not be executed in a function.
04:54 fi indicates the end of if statement.
04:58 Here the function name is exit_(Undescore)function .
05:02 The if statement here compares two variables.
05:06 If the two variables are equal then the commands in 'if' are executed.
05:14 This echo statement displays the message "This is exit function" .
05:19 exit 0 will terminate the program.
05:23 fi indicates the end of this if statement.
05:27 This is a function call with arguments 3 and 3.
05:33 This displays the message "We are in main program".
05:38 This is another function call with arguments 3 and 3.
05:44 This echo statement displays the message "This line is not displayed".
05:49 Note that exit will terminate the program.
05:53 Anything after exit will not be executed.
05:58 Save the file and go to the terminal.
06:00 Type: chmod space plus x space return underscore exit dot sh
06:09 Press Enter.
06:12 Type: dot slash return underscore exit dot sh
06:18 Press Enter.
06:20 The output displays the messages as shown.
06:24 Now, let us understand the flow of the program.
06:27 The control will be in main program which is the script itself.
06:33 The control goes to return_function because of the function call.
06:39 As the two variables are equal, it displays the message '"This is return function.
06:47 Then it encounters return 0. And the control flows from function to the statement below the function call, in the main program.
06:59 Then it displays the message "We are in main program" .
07:03 After that, the control goes to exit_function because of the function call.
07:11 As the two variables are equal, it displays the message "This is exit function".
07:19 Then it encounters exit 0. This will terminate the program.
07:25 Any statement after exit will not be executed.
07:30 Also, the statement This line is not displayed will not be executed.
07:36 Hope the difference is clear to you.
07:39 Let us now summarize.
07:41 In this tutorial, we learnt:
07:44 * To pass an array to a function
07:47 * Use of exit statement in a function
07:50 * Use of return statement in a function
07:53 with the help of some examples.
07:56 As an assignment-
07:57 Write a program
07:58 where a function adds all the elements in an array. The function should display the sum of elements.
08:07 Make 2 function calls with array elements (1, 2, 3) and (4, 5, 6).
08:15 Watch the video available at the link shown below. http://spoken-tutorial.org /What_is_a_Spoken_Tutorial.
08:19 It summarizes the Spoken Tutorial project.
08:23 If you do not have good bandwidth, you can download and watch it.
08:28 The Spoken Tutorial Project Team:
08:30 Conducts workshops using spoken tutorials.

Gives certificates to those who pass an online test. For more details, please write to contact@spoken-tutorial.org

08:45 Spoken Tutorial Project is a part of the Talk to a Teacher project.
08:49 It is supported by the National Mission on Education through ICT, MHRD, Government of India. More information on this mission is available at the link shown below. http://spoken-tutorial.org\NMEICT-Intro
09:04 The script has been contributed by FOSSEE and Spoken-Tutorial teams.
09:10 This is Ashwini Patil from IIT Bombay, signing off. Thank you for joining.

Contributors and Content Editors

Pratik kamble, Sandhya.np14

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