Difference between revisions of "Linux/C3/More-on-sed-command/English-timed"

|  In this tutorial, we will learn some more on '''sed commands''' through some examples.

| '''Ubuntu Linux''' version 12.04''' Operating System''' and

| '''GNU BASH''' version 4.2.24

| You should be aware of '''sed''' tool.

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

|  Let's first look at the original file '''seddemo.txt'''.

|  Notice that the word "Kumar" occurs two times in the fourth line and once in the sixth line.

| If you want to replace all occurrences of "Kumar" with "Roy",

|type on the '''terminal''':

| '''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'''

| Only the first occurrence of "Kumar" is changed to "Roy", not the second one.

| Sixth line had one occurrence of the word "Kumar" and this is replaced now.

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

|  Let me clear the prompt.  

| 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'''.

| Say, we want to replace the word "electronics" with the word "electrical"

| and "civil" with "metallurgy" in the file '''seddemo.txt'''.

|  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'''

| Press '''Enter.'''

|  Now we want to change the '''stream''' of 'Anirban' from "computers" to "mathematics."

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

| First we write '''sed''', then in single quotes we write the pattern to be matched.

| This is "Anirban".

| This is 's' that stands for substitution as we have already seen.

| Then we mention the pattern to be replaced which is "computers".

| Then the new word that would be substituted which is "mathematics".

| Say, we want to select those lines which do not have '''stream''' as "electronics."

|  For that, we have the '''d flag'''.

| 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'''

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

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

| Say, we want to add the two lines. We would do it in a similar way.

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

| Press '''Enter'''.

| '''slash n''' prints 2013 in the next line after ‘Student Information’.

|  This brings us to the end of this tutorial.

| In this tutorial we learnt:

| Substitution Replacement

| And Insertion.

|  As an assignment, use the same text file '''seddemo.txt'''

| and try to replace or substitute name "Ankit" with "Ashish".

| It summarizes the Spoken Tutorial project.

| If you do not have good bandwidth, you can download and watch it.

|  The Spoken Tutorial Project Team: Conducts workshops using spoken tutorials.

| Gives certificates to those who pass an online test.

|  Spoken Tutorial Project is a part of the Talk to a Teacher project.

| 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.

|This is Ashwini PAtil from IIT Bombay, signing off.