Linux/C3/More-on-sed-command/English-timed - Revision history

PoojaMoolya at 12:31, 23 March 2017

2017-03-23T12:31:26Z

PoojaMoolya at 07:12, 10 March 2017

2017-03-10T07:12:11Z

Sandhya.np14 at 09:39, 13 March 2015

2015-03-13T09:39:52Z

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Gaurav at 12:13, 22 July 2014

2014-07-22T12:13:32Z

Gaurav at 12:13, 22 July 2014

2014-07-22T12:13:13Z

Gaurav: Created page with ' {| border=1 | '''Time''' | '''Narration''' |- | 00:01 | Welcome to the spoken tutorial on '''More on sed.''' |- | 00:06 | In this tutorial, we will learn some '''More …'

2014-07-22T12:11:34Z

Created page with ' {| border=1 | '''Time''' | '''Narration''' |- | 00:01 | Welcome to the spoken tutorial on '''More on sed.''' |- | 00:06 | In this tutorial, we will learn some '''More …'

New page

{| border=1
| '''Time'''
| '''Narration'''

|-
| 00:01
| Welcome to the spoken tutorial on '''More on sed.'''

|-
| 00:06
| In this tutorial, we will learn some '''More on sed '''commands, through some examples.

|-
| 00:13
| To record this tutorial, I am using

|-
| 00:15
| *'''Ubuntu Linux''' version 12.04''' Operating System''' and

|-
| 00:20
| *'''GNU BASH''' version 4.2.24

|-
| 00:24
| Please note,''' GNU Bash''' version 4 or above is recommended to practice this tutorial.

|-
| 00:32
| As prerequisites,

|-
| 00:34
| You should know basics of '''Linux terminal.'''

|-
| 00:37
| You should be aware of sed tool.

|-
| 00:40
| For relevant tutorials please visit our website which as shown: http://spoken-tutorial.org

|-
| 00:46
| The major use of '''sed''' is substitution.

|-
| 00:49
| Replacing some pattern in the input with something else.

|-
| 00:55
| Let's first look at the original file '''seddemo.txt'''

|-
| 01:01
| Notice the word '''Kumar''' occurs two times in the fourth line and once in the sixth line.

|-
| 01:10
| If you want to replace all occurrences of '''‘Kumar’''' with '''‘Roy’'''

|-
| 01:16
|Type on the '''terminal'''

|-
| 01:18
| '''sed space''' within single quote ''''s front slash / opening square bracket small ''k'' capital ''K'' closing square bracket umar slash Roy slash'''' after the single quotes space '''seddemo.txt'''

|-
| 01:40
| Press '''Enter'''.

|-
| 01:43
| Notice the fourth line.

|-
| 01:46
| Only the first occurrence of '''Kumar''' is changed to '''Roy''', not the second one.

|-
| 01:52
| Sixth line had one occurrence of the word '''Kumar''' and this is replaced now.

|-
| 01:57
| So, we see only the first entry of the lines has been changed.

|-
| 02:03
| This is because, by default, the first matched entry of any line is substituted.

|-
| 02:11
| To substitute all the matched entries we need to use the flag ''' g''' option.

|-
| 02:17
| Let me clear the '''prompt. '''

|-
| 02:20
| Type '''sed space within single quotes 's front slash opening square bracket ''small k'' ''capital K'' closing square bracket umar slash Roy slash g'''' after the single quote space '''seddemo.txt''' Press '''Enter'''

|-
| 02:43
| Now, both entries of the fourth line are replaced.

|-
| 02:48
| We can make multiple substitutions in one go as well.

|-
| 02:53
| Say we want to replace the words '''electronics''' with the word '''electrical'''

|-
| 02:58
| And '''civil''' with '''metallurgy''' in the file '''seddemo.txt'''

|-
| 03:04
|Let me clear the '''prompt'''

|-
| 03:07
| Type '''sed space hyphen '''e''' space within single quotes ‘s front slash electronics slash electrical slash g’ after the single quote space hyphen '''e''' space within single quotes ‘s front slash civil slash metallurgy slash g’''' after the single quotes space '''seddemo.txt'''

|-
| 03:37
| And press '''Enter.'''

|-
| 03:39
| You can see that the words are replaced.

|-
| 03:43
| Now we want to change the '''stream''' of '''Anirban '''from '''computers''' to '''mathematics.'''

|-
| 03:49
| In such case we would need to type:

|-
| 03:54
| '''sed space''' within single quotes ''''front slash Anirban slash s slash computers slash mathematics slash g' ''' after the single quotes space '''seddemo.txt'''

|-
| 04:11
| Press '''Enter.'''

|-
| 04:14
| We see that the '''stream''' is changed.

|-
| 04:17
| Let us understand what this is.

|-
| 04:21
| First we write '''sed''' then in single quotes we write the pattern to be matched.

|-
| 04:28
| This is '''Anirban'''.

|-
| 04:30
| Now after the slash comes the operation.

|-
| 04:34
| This is '''s''' that stands for substitution, as we have already seen.

|-
| 04:41
| Then we mention the pattern to be replaced which is '''computers'''.

|-
| 04:47
| Then the new word that would be substituted, which is '''mathematics'''.

|-
| 04:53
| We can also use '''sed''' to add or delete lines in the file.

|-
| 05:00
| Say we want to select those lines which do not have '''stream''' as '''electronics.'''

|-
| 05:06
| For that, we have the '''d '''flag.

|-
| 05:10
| Type:
'''sed space''' within single quotes '''front slash electronics slash d''' after the single quotes '''space seddemo.txt space greater than sign space nonelectronics.txt'''

|-
| 05:31
| Press '''Enter'''.

|-
| 05:33
| To see the contents, type: '''cat space nonelectronics.txt'''

|-
| 05:43
| Say, at the start of the file we want to add a line '''Student Information'''.

|-
| 05:49
| For that we have the '''i''' action.

|-
| 05:54
| We need to type: '''sed space''' in single quotes ''''1i space Student Information' after the quote seddemo.txt '''

|-
| 06:10
| And press '''Enter.'''

|-
| 06:13
| You can see the output.

|-
| 06:15
| In fact, we can enter multiple lines like this.

|-
| 06:20
| Say, we want to add the two lines we would do it in a similar way.

|-
| 06:26
| Along with '''Student Information''' we also want to add '''academics''' in the next year.

|-
| 06:33
| So in that case we would write
'''sed space''' in single quotes '''1i space Student Information slash n 2013'''' after the quotes '''seddemo.txt'''

|-
| 06:55
| Press '''Enter'''

|-
| 06:57
| Notice '''slash n''' between the string ‘Information’ and ‘2013’.

|-
| 07:05
| '''slash n '''prints 2013 in the next line after ‘Student Information’

|-
| 07:12
| This brings me to the end of this tutorial.

|-
| 07:14
| Let us summarize,

|-
| 07:17
| In this tutorial we learnt,

|-
| 07:19
| Substitution

|-
| 07:20
| Replacement

|-
| 07:21
| And Insertion

|-
| 07:24
| As an assignment, Use the same text file '''seddemo.txt'''

|-
| 07:30
| And try to replace or substitute name '''Ankit''' with '''Ashish'''

|-
| 07:35
| Watch the video available at the link shown below http://spoken-tutorial.org/What_is_a_Spoken Tutorial

|-
| 07:39
| It summarises the Spoken Tutorial project

|-
| 07:42
| If you do not have good bandwidth, you can download and watch it

|-
| 07:47
| The Spoken Tutorial Project Team Conducts workshops using spoken tutorials

|-
| 07:53
| Gives certificates to those who pass an online test

|-
| 07:57
| For more details, please write to contact@spoken-tutorial.org

|-
| 08:04
| Spoken Tutorial Project is a part of the Talk to a Teacher project

|-
| 08:09
| It is supported by the National Mission on Education through ICT, MHRD, Government of India

|-
| 08:16
| More information on this Mission is available at the link shown below: http://spoken-tutorial.org\NMEICT-Intro

|-
| 08:22
| The script has been contributed by Anirban and Sachin.

|-
| 08:28
|This is Ashwini PAtil from IIT bombay signing off.

Thank you for joining.

|}

@@ Line 106: / Line 106: @@
 |-
 |  02:20
-| Type:
+| Type:  '''sed space''' (within single quotes)''' 's front-slash opening square bracket small k capital K closing square bracket umar slash Roy slash g' ''' after the single quote space '''seddemo.txt'''. Press '''Enter'''.
   '''sed space''' (within single quotes)''' 's front-slash opening square bracket small k capital K closing square bracket umar slash Roy slash g' ''' after the single quote space '''seddemo.txt'''. Press '''Enter'''.
 |-
@@ Line 131: / Line 130: @@
 |-
 |  03:07
-|  Type:
+|  Type: '''sed space hyphen e space''' within single quotes '''‘s front slash electronics slash electrical slash g’ after the single quote space hyphen e space''' within single quotes ''' ‘s front-slash civil slash metallurgy slash g’ ''' after the single quotes space '''seddemo.txt'''
- '''sed space hyphen e space''' within single quotes '''‘s front slash electronics slash electrical slash g’ after the single quote space hyphen e space''' within single quotes ''' ‘s front-slash civil slash metallurgy slash g’ ''' after the single quotes space '''seddemo.txt'''
 |-
@@ Line 204: / Line 202: @@
 |-
 |  05:10
-| Type:
+| Type:  '''sed space''' within single quotes '''front-slash electronics slash d''' after the single quotes '''space seddemo.txt space greater than sign space nonelectronics.txt'''
   '''sed space''' within single quotes '''front-slash electronics slash d''' after the single quotes '''space seddemo.txt space greater than sign space nonelectronics.txt'''
 |-
@@ Line 249: / Line 246: @@
 |-
 |  06:33
-|  So in that case we would write
+|  So in that case we would write '''sed space''' in single quotes '''1i space Student Information slash n 2013''' after the quotes '''seddemo.txt'''
- '''sed space''' in single quotes '''1i space Student Information slash n 2013''' after the quotes '''seddemo.txt'''
 |-

@@ Line 18: / Line 18: @@
 |-
 |  00:15
-| *'''Ubuntu Linux''' version 12.04''' Operating System''' and
+|  '''Ubuntu Linux''' version 12.04''' Operating System''' and
 |-
 |  00:20
-| *'''GNU BASH''' version 4.2.24
+| '''GNU BASH''' version 4.2.24
 |-
@@ Line 278: / Line 278: @@
 |-
 |  07:19
-|* Substitution
+| Substitution Replacement
-−
-|-
-|  07:20
-|* Replacement
 |-
 |  07:21
-|* And Insertion.
+| And Insertion.
 |-

@@ Line 1: / Line 1: @@
 {| border=1
@@ Line 162: / Line 161: @@
 |  04:14
 | We see that the '''stream''' is changed.
 |-

@@ Line 1: / Line 1: @@
@@ Line 108: / Line 107: @@
 |-
 |  02:20
-| Type '''sed space within single quotes 's front slash opening square bracket ''small k'' ''capital K'' closing square bracket umar slash Roy slash g'''' after the single quote space '''seddemo.txt''' Press '''Enter'''
+| Type:
 |-
@@ Line 132: / Line 132: @@
 |-
 |  03:07
-|  Type '''sed space  hyphen '''e''' space within single quotes ‘s front slash electronics slash electrical slash g’  after the single quote space hyphen '''e''' space within single quotes  ‘s front slash civil slash metallurgy slash g’''' after the single quotes space '''seddemo.txt'''
+|  Type:
 |-
@@ Line 247: / Line 248: @@
 |  06:26
 | Along with '''Student Information''' we also want to add '''academics''' in the next year.
 |-