Difference between revisions of "Linux/C3/The-grep-command/English-timed"

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|-
 
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|00:01
 
|00:01
|Welcome to the spoken tutorial on '''grep''' command
+
|Welcome to the spoken tutorial on '''grep''' command.
  
 
|-
 
|-
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|-
 
|-
 
|00:15
 
|00:15
|*'''Ubuntu Linux''' 12.04''' Operating System'''  
+
|'''Ubuntu Linux''' 12.04''' Operating System'''  
  
 
|-
 
|-
 
|00:20
 
|00:20
| and *'''GNU BASH''' version 4.2.24
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| and '''GNU BASH''' version 4.2.24.
  
 
|-
 
|-
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|-
 
|-
 
|00:32
 
|00:32
|As prerequisitesYou should know basics of '''Linux terminal'''
+
|As prerequisites you should know basics of '''Linux terminal'''.
  
 
|-
 
|-
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|-
 
|-
 
|00:41
 
|00:41
|First let us know about regular expressions.
+
|First let us know about '''regular expressions'''.
  
 
|-
 
|-
 
|00:45
 
|00:45
|*Regular expressions are pattern matching techniques.
+
| Regular expressions are pattern matching techniques
  
 
|-
 
|-
 
|00:50
 
|00:50
|*When we have to find out whether a pattern exist in a line, paragraph or a file.
+
| when we have to find out whether a pattern exist in a line, paragraph or a file.
  
 
|-
 
|-
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|-
 
|-
 
| 01:02
 
| 01:02
Or To find a keyword in a paragraph or a line, we use '''grep command'''
+
or to find a keyword in a paragraph or a line, we use '''grep command'''.Let us move on to '''grep'''.
Let us move on to '''grep'''.
+
  
 
|-
 
|-
 
|01:11
 
|01:11
|'''grep''' searches for one or more patterns in one or more line, paragraph or a file.
+
|'''grep''' searches for one or more patterns in one or more lines, paragraphs or a file.
  
 
|-
 
|-
 
|01:17
 
|01:17
|If filename is not mentioned,''' grep''' search for the patterns in the standard input.
+
|If file name is not mentioned, '''grep''' searches for the patterns in the standard input.
  
 
|-
 
|-
 
|01:23
 
|01:23
|If filename is missing, '''grep''' searches for the patterns in the standard input.
+
|If file name is missing, '''grep''' searches for the patterns in the standard input.
  
 
|-
 
|-
 
|01:30
 
|01:30
|I will demonstrate usage of '''grep''' using a demo file called '''grepdemo.txt'''
+
|I will demonstrate usage of '''grep''' using a demo file called '''grepdemo.txt'''.
  
 
|-
 
|-
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|-
 
|-
 
|01:44
 
|01:44
|Each entry has 6 fields roll number, name, stream, marks, and stipend amount.  
+
|Each entry has 6 fields: roll number, name, stream, marks, and stipend amount.  
  
 
|-
 
|-
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|-
 
|-
 
|02:10
 
|02:10
|So press '''CTRL + ALT and T''' keys simultaneously on your keyboard.
+
|So press '''Ctrl + Alt''' and '''T''' keys simultaneously on your keyboard.
  
 
|-
 
|-
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|-
 
|-
 
|02:18
 
|02:18
|'''grep space (within double quotes) computers after the double quotes space  grepdemo .txt'''
+
|'''grep space''' (within double quotes) '''computers''' after the double quotes '''space  grepdemo .txt'''
  
 
|-
 
|-
 
|02:27
 
|02:27
|Press Enter
+
|Press Enter.This would enlist those entries where stream is '''computers'''.
 
+
|-
+
|02:28
+
|This would enlist those entries where stream is '''computers'''.
+
  
 
|-
 
|-
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|-
 
|-
 
|02:45
 
|02:45
|Why this is so?
+
|Why this is so? This is because '''grep''' searched for the pattern “computers” with small '''c'''.
 
+
 
+
|-
+
|02:46
+
|This is because '''grep''' searched for the pattern '''“computers”''' with small '''c'''  
+
  
 
|-
 
|-
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|-
 
|-
 
|03:00
 
|03:00
|To make it '''case''' insensitive, we need to use the '''minus i ''' option with '''grep'''.
+
|To make it '''case insensitive''', we need to use the '''minus i ''' (-i) option with '''grep'''.
  
 
|-
 
|-
 
|03:06
 
|03:06
|From back to our terminal Now Type:
+
|Come back to our terminal, now type:'''grep space (minus) i space''' (within double quotes) '''“computers”''' after the double quotes '''space grepdemo.txt'''
'''grep space (minus) i space (within double quotes) '''computers”''' after the '''double quotes space grepdemo.txt'''
+
  
 
|-
 
|-
 
|03:20
 
|03:20
|Press ''' Enter.'''
+
|Press '''Enter'''. This will now enlist all the four entries.
 
+
|-
+
|03:21
+
|This will now enlist all the four entries.
+
  
 
|-
 
|-
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|-
 
|-
 
|03:48
 
|03:48
|We can also store this result in another file
+
|We can also store this result in another file.
 
+
  
 
|-
 
|-
 
|03:52
 
|03:52
|For this type:
+
|For this type: '''grep space minus iv space''' within double quotes '''pass''' after the double quotes '''space grepdemo.txt space greater than sign space notpass.txt '''
'''grep space minus iv space''' Within double quotes '''pass after the double quotes space grepdemo.txt space greater than sign space notpass.txt '''
+
  
 
|-
 
|-
 
|04:11
 
|04:11
|Press '''Enter.'''
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|Press '''Enter.''' To see the content of file, type: '''cat space notpass.txt '''
 
+
|-
+
|04:12
+
|To see the content of file, type:
+
'''cat space notpass.txt '''
+
  
 
|-
 
|-
 
|04:20
 
|04:20
|Press '''Enter'''.
+
|Press '''Enter'''.The output is displayed.
 
+
|-
+
|04:21
+
|The output is displayed.
+
  
 
|-
 
|-
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|-
 
|-
 
|04:37
 
|04:37
|And Press '''Enter.'''
+
|And Press '''Enter.'''This is different.
 
+
|-
+
|04:38
+
|This is different.
+
 
    
 
    
 
|-
 
|-
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|-
 
|-
 
|04:54
 
|04:54
|Let us clear the '''prompt'''.  
+
|Let us clear the prompt.  
  
 
|-
 
|-
 
|04:58
 
|04:58
|  Now type "'''grep space -in space within double quote "fail" after the double quotes space grepdemo.txt'''
+
|  Now type '''grep space -in space''' within double quote "fail" after the double quotes '''space grepdemo.txt'''.
  
 
|-
 
|-
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|-
 
|-
 
|05:18
 
|05:18
|We may have multiword patterns as well.  
+
|We may have multi-word patterns as well.  
  
 
|-
 
|-
 
|05:21
 
|05:21
|But the entire pattern must be within '''quotes'''.
+
|But the entire pattern must be within quotes.
  
 
|-
 
|-
 
|05:24
 
|05:24
|So type: '''grep space minus i space'''within double quotes '''ankit space saraf after the double quotes space grepdemo.txt '''
+
|So, type: '''grep space minus i space'''within double quotes '''ankit space saraf''' after the double quotes '''space grepdemo.txt '''
  
 
|-
 
|-
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|-
 
|-
 
|05:48
 
|05:48
|For this Type:
+
|For this, type: '''grep space minus i space''' within double quotes '''fail''' after double quotes space '''grepdemo.txt space notpass.txt'''  
'''grep space minus i space''' within double quotes '''fail after double quotes space grepdemo.txt space notpass.txt'''  
+
  
 
|-
 
|-
 
|06:03
 
|06:03
|'''Press Enter'''.
+
|'''Press Enter'''. The output is displayed.
 
+
|-
+
|06:04
+
|The output is displayed.
+
  
 
|-
 
|-
 
|06:07
 
|06:07
|With multiple files, '''grep''' will write the name of the file in which the entry was found.'''grepdemo.txt''' and '''notpass.txt'''
+
|With multiple files, '''grep''' will write the name of the file in which the entry was found. '''grepdemo.txt''' and '''notpass.txt'''.
  
 
|-
 
|-
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|-
 
|-
 
|06:26
 
|06:26
|Suppose we may only want to know the '''number of matches '''or '''count''' .
+
|Suppose, we may only want to know the '''number of matches '''or '''count'''.
  
 
|-
 
|-
 
|06:31
 
|06:31
|For that, we have the '''minus c''' option
+
|For that, we have the '''minus c''' option.
  
 
|-
 
|-
 
|06:35
 
|06:35
| So Type: '''grep space minus c space'''within double quotes '''Fail  with a capital F after the quotes space grepdemo.txt'''
+
| So, type: '''grep space minus c space'''within double quotes '''Fail''' with a capital F after the quotes '''space grepdemo.txt'''
  
 
|-
 
|-
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|-
 
|-
 
| 07:01
 
| 07:01
| In this tutorial we learnt,
+
| In this tutorial we learnt:
  
 
|-
 
|-
 
|07:03
 
|07:03
|*To see the content of a file
+
|To see the contents of a file eg. '''cat filename'''
**eg. '''cat filename'''
+
 
 
|-
 
|-
 
|07:07
 
|07:07
|*To list the entries of a particular stream
+
| To list the entries of a particular stream eg. '''grep “computers” grepdemo.txt'''
**eg. '''grep “computers” grepdemo.txt'''
+
  
 
|-
 
|-
 
|07:14
 
|07:14
|*To ignore cases
+
|To ignore cases eg. '''grep -i “computers” grepdemo.txt'''
**eg. '''grep -i “computers” grepdemo.txt'''
+
  
 
|-
 
|-
 
|07:21
 
|07:21
|*Lines that do not match the pattern
+
| Lines that do not match the pattern eg. '''grep -iv “pass” grepdemo.txt'''
**eg. '''grep -iv “pass” grepdemo.txt'''
+
  
 
|-
 
|-
 
|07:30
 
|07:30
|*To list the line numbers with the entries
+
|To list the line numbers with the entries eg.''' grep -in “fail” grepdemo.txt'''
**eg.''' grep -in “fail” grepdemo.txt'''
+
  
 
|-
 
|-
 
|07:38
 
|07:38
|*To store the result in another file
+
|To store the result in another file eg. '''grep -iv “pass” grepdemo.txt > notpass.txt'''
**eg. '''grep -iv “pass” grepdemo.txt > notpass.txt'''
+
  
 
|-
 
|-
 
|07:50
 
|07:50
|And*To know the count
+
|And To know the count eg.''' grep -c “Fail” grepdemo.txt'''.
**eg.''' grep -c “Fail” grepdemo.txt'''
+
  
 
|-
 
|-
 
|07:57
 
|07:57
|As an assignment,
+
|As an assignment,Explore some other commands like '''-E, + and ?'''.
 
+
|-
+
|07:58
+
|Explore some other commands like '''-E, + and ?'''
+
  
 
|-
 
|-
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|-
 
|-
 
|08:06
 
|08:06
|It summarises the Spoken Tutorial project.
+
|It summarizes the Spoken Tutorial project.
  
 
|-
 
|-
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|-
 
|-
 
|08:14
 
|08:14
|The Spoken Tutorial Project Team
+
|The Spoken Tutorial Project Team:
  
 
|-
 
|-
 
|08:16
 
|08:16
|*Conducts workshops using spoken tutorials
+
|Conducts workshops using spoken tutorials
  
 
|-
 
|-
 
|08:19
 
|08:19
|*Gives certificates to those who pass an online test
+
|Gives certificates to those who pass an online test.
  
 
|-
 
|-
 
|08:23
 
|08:23
|For more details, please write to
+
|For more details, please write to'''contact@spoken-tutorial.org'''
'''contact@spoken-tutorial.org'''
+
  
 
|-
 
|-
 
|08:30
 
|08:30
|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.
  
 
|-
 
|-
 
|08:33
 
|08:33
|It is supported by the National Mission on Education through ICT, MHRD, Government of India
+
|It is supported by the National Mission on Education through ICT, MHRD, Government of India.
  
 
|-
 
|-
 
|08:40
 
|08:40
|More information on this Mission is available at: http://spoken-tutorial.org\NMEICT-Intro
+
|More information on this Mission is available at: http://spoken-tutorial.org\NMEICT-Intro.
  
 
|-
 
|-
 
|08:45
 
|08:45
|This is Ashwini Patil from IIT Bombay signning off. Thank you for joining.
+
|This is Ashwini Patil from IIT Bombay, signing off. Thank you for joining.
 
+
|-
 
|}
 
|}

Latest revision as of 11:04, 17 October 2017

Time Narration
00:01 Welcome to the spoken tutorial on grep command.
00:05 In this tutorial we will learn grep command.
00:09 We will do this with the help of some examples.
00:11 To record this tutorial, I am using
00:15 Ubuntu Linux 12.04 Operating System
00:20 and 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 you should know basics of Linux terminal.
00:36 For relevant tutorials, please visit our website which is as shown.
00:41 First let us know about regular expressions.
00:45 Regular expressions are pattern matching techniques
00:50 when we have to find out whether a pattern exist in a line, paragraph or a file.
00:56 For ex. If you want to search a phone number in the telephone directory
01:02 or to find a keyword in a paragraph or a line, we use grep command.Let us move on to grep.
01:11 grep searches for one or more patterns in one or more lines, paragraphs or a file.
01:17 If file name is not mentioned, grep searches for the patterns in the standard input.
01:23 If file name is missing, grep searches for the patterns in the standard input.
01:30 I will demonstrate usage of grep using a demo file called grepdemo.txt.
01:37 Let us see the content of the file.
01:40 This is a file that has 13 entries.
01:44 Each entry has 6 fields: roll number, name, stream, marks, and stipend amount.
01:52 The fields are separated by a bar, which is called a delimiter.
01:56 Let us see how grep works.
02:00 Say we want to use grep command, to see who are the students in the computers stream.
02:07 For this we have to open the terminal.
02:10 So press Ctrl + Alt and T keys simultaneously on your keyboard.
02:16 Now type on the terminal:
02:18 grep space (within double quotes) computers after the double quotes space grepdemo .txt
02:27 Press Enter.This would enlist those entries where stream is computers.
02:33 Now compare the result with the original file.
02:37 Come back to our text editor.
02:40 We see that the entry for Zubin is not enlisted.
02:45 Why this is so? This is because grep searched for the pattern “computers” with small c.
02:52 While for Zubin, the stream is “Computers” with a capital C.
02:57 The pattern matching is case sensitive.
03:00 To make it case insensitive, we need to use the minus i (-i) option with grep.
03:06 Come back to our terminal, now type:grep space (minus) i space (within double quotes) “computers” after the double quotes space grepdemo.txt
03:20 Press Enter. This will now enlist all the four entries.
03:25 So we saw, grep enlists only those lines of files that match a given pattern.
03:32 We may do the reverse.
03:34 It is possible to make grep enlist only those lines that do not match the pattern.
03:40 For that we have the minus v option.
03:43 Say, we want to enlist those entries of students who have not passed.
03:48 We can also store this result in another file.
03:52 For this type: grep space minus iv space within double quotes pass after the double quotes space grepdemo.txt space greater than sign space notpass.txt
04:11 Press Enter. To see the content of file, type: cat space notpass.txt
04:20 Press Enter.The output is displayed.
04:24 Now at the prompt type:
04:26 grep space minus i space' within double quotes fail after the double quotes space grepdemo.txt
04:37 And Press Enter.This is different.
04:41 This will include those students who are failed but their result is incomplete.
04:46 If we want to see the line number in the file at which the enlisted entries are, we have the minus n option
04:54 Let us clear the prompt.
04:58 Now type grep space -in space within double quote "fail" after the double quotes space grepdemo.txt.
05:09 Press Enter.
05:11 The line number is displayed.
05:15 The patterns so far have been of single word.
05:18 We may have multi-word patterns as well.
05:21 But the entire pattern must be within quotes.
05:24 So, type: grep space minus i spacewithin double quotes ankit space saraf after the double quotes space grepdemo.txt
05:38 Press Enter.
05:40 We see that Ankit Saraf's record is displayed.
05:44 We can also find patterns in multiple files.
05:48 For this, type: grep space minus i space within double quotes fail after double quotes space grepdemo.txt space notpass.txt
06:03 Press Enter. The output is displayed.
06:07 With multiple files, grep will write the name of the file in which the entry was found. grepdemo.txt and notpass.txt.
06:18 These are the records from notpass.txt file and these are the records from grepdemo.txt file.
06:26 Suppose, we may only want to know the number of matches or count.
06:31 For that, we have the minus c option.
06:35 So, type: grep space minus c spacewithin double quotes Fail with a capital F after the quotes space grepdemo.txt
06:48 Press Enter.
06:50 This will give us the count of number of lines matched.
06:55 This brings us to the end of this tutorial.
06:59 Let us summarize.
07:01 In this tutorial we learnt:
07:03 To see the contents of a file eg. cat filename
07:07 To list the entries of a particular stream eg. grep “computers” grepdemo.txt
07:14 To ignore cases eg. grep -i “computers” grepdemo.txt
07:21 Lines that do not match the pattern eg. grep -iv “pass” grepdemo.txt
07:30 To list the line numbers with the entries eg. grep -in “fail” grepdemo.txt
07:38 To store the result in another file eg. grep -iv “pass” grepdemo.txt > notpass.txt
07:50 And To know the count eg. grep -c “Fail” grepdemo.txt.
07:57 As an assignment,Explore some other commands like -E, + and ?.
08:04 Watch the video available at the link shown below.
08:06 It summarizes the Spoken Tutorial project.
08:10 If you do not have good bandwidth, you can download and watch it.
08:14 The Spoken Tutorial Project Team:
08:16 Conducts workshops using spoken tutorials
08:19 Gives certificates to those who pass an online test.
08:23 For more details, please write tocontact@spoken-tutorial.org
08:30 Spoken Tutorial Project is a part of the Talk to a Teacher project.
08:33 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
08:40 More information on this Mission is available at: http://spoken-tutorial.org\NMEICT-Intro.
08:45 This is Ashwini Patil from IIT Bombay, signing off. Thank you for joining.

Contributors and Content Editors

Madhurig, PoojaMoolya, Pratik kamble, Sandhya.np14