Difference between revisions of "BASH/C3/Here-document-and-Here-string/English-timed"

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|  '''Narration'''

|  '''Narration'''

|-

|-

|  Dear friends, Welcome to the spoken tutorial on''' HERE document and strings'''

|  Dear friends, Welcome to the spoken tutorial on''' HERE document and strings'''

|-

|-

|  In this tutorial, we will learn about

|  In this tutorial, we will learn about

|-

|-

| * special-purpose redirection called '''Here documents '''and '''Here strings'''

| * special-purpose redirection called '''Here documents '''and '''Here strings'''

|-

|-

| * With the help of some examples  

| * With the help of some examples  

|-

|-

|  To follow this tutorial you should have knowledge of '''Shell Scripting''' in''' BASH.'''

|  To follow this tutorial you should have knowledge of '''Shell Scripting''' in''' BASH.'''

|-

|-

|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)'''

|-

|-

|  For this tutorial I am using''' '''

|  For this tutorial I am using''' '''

|-

|-

|* '''Ubuntu Linux''' 12.04''' '''Operating System  

|* '''Ubuntu Linux''' 12.04''' '''Operating System  

|-

|-

|* '''GNU BASH''' version 4.2

|* '''GNU BASH''' version 4.2

|-

|-

|Please note,''' GNU Bash''' '''version 4''' or above is recommended for practice.

|Please note,''' GNU Bash''' '''version 4''' or above is recommended for practice.

|-

|-

|  Let us learn about '''Here document'''.

|  Let us learn about '''Here document'''.

|-

|-

|* It is a special-purpose block of text or code.  

|* It is a special-purpose block of text or code.  

|-

|-

|* It is a form of I/O redirect.

|* It is a form of I/O redirect.

|-

|-

|* It feeds a command list to an interactive program or command line.

|* It feeds a command list to an interactive program or command line.

|-

|-

|* It can be treated as a separate file.

|* It can be treated as a separate file.

|-

|-

|* It can also be treated as multiple line input redirected to a shell script.

|* It can also be treated as multiple line input redirected to a shell script.

|-

|-

|  Syntax is,

|  Syntax is,

|-

|-

|'''command space less than less than space HERE'''.

|'''command space less than less than space HERE'''.

|-

|-

|After this on the next line, we can give the text inputs.  

|After this on the next line, we can give the text inputs.  

|-

|-

|It can consist of any number of lines.

|It can consist of any number of lines.

|-

|-

|Here, '''text1, text2, textN''' are the text inputs.

|Here, '''text1, text2, textN''' are the text inputs.

|-

|-

|After the text inputs, on the next line, we type the keyword '''HERE '''again.

|After the text inputs, on the next line, we type the keyword '''HERE '''again.

|-

|-

|It denotes the closing of '''HERE document.'''

|It denotes the closing of '''HERE document.'''

|-

|-

|  Let us understand this with an example.  

|  Let us understand this with an example.  

|-

|-

|I will open a file named '''here dot sh '''

|I will open a file named '''here dot sh '''

|-

|-

|  The first line of code is the '''shebang line.'''

|  The first line of code is the '''shebang line.'''

|-

|-

|  Let me put a block of code after this line.

|  Let me put a block of code after this line.

|-

|-

| wc represents word count  

| wc represents word count  

|-

|-

| '''wc hyphen w counts the number of words in the '''HERE''' document

| '''wc hyphen w counts the number of words in the '''HERE''' document

|-

|-

|The block of code or text until the second occurance of '''HERE''' will be treated as a file  

|The block of code or text until the second occurance of '''HERE''' will be treated as a file  

|-

|-

|The content present in '''HERE''' document is an input to the command '''wc hyphen w'''

|The content present in '''HERE''' document is an input to the command '''wc hyphen w'''

|-

|-

|  '''HERE''' acts as a delimiter for '''wc hyphen w''' command while reading multi-line input.

|  '''HERE''' acts as a delimiter for '''wc hyphen w''' command while reading multi-line input.

|-

|-

|If we try to execute the same command in the '''terminal''', we should get ''''4'''' as an output.

|If we try to execute the same command in the '''terminal''', we should get ''''4'''' as an output.

|-

|-

|This is because we have passed four words to the command ''''wc hyphen w''''.  

|This is because we have passed four words to the command ''''wc hyphen w''''.  

|-

|-

|Now click on '''Save''' to save the file.

|Now click on '''Save''' to save the file.

|-

|-

|  Let us switch to the '''Terminal''' using '''Ctrl, Alt''' and '''T''' keys simultaneously on your keyboard.

|  Let us switch to the '''Terminal''' using '''Ctrl, Alt''' and '''T''' keys simultaneously on your keyboard.

|-

|-

| Type: '''chmod space plus x space here dot sh'''

| Type: '''chmod space plus x space here dot sh'''

|-

|-

|Press '''Enter.'''

|Press '''Enter.'''

|-

|-

|Type '''dot slash here dot sh'''

|Type '''dot slash here dot sh'''

|-

|-

|Press '''Enter.'''

|Press '''Enter.'''

|-

|-

|  We can see the output as '''4.'''

|  We can see the output as '''4.'''

|-

|-

|That is, number of words in '''Here document '''is '''4.'''

|That is, number of words in '''Here document '''is '''4.'''

|-

|-

|  Come back to the program.

|  Come back to the program.

|-

|-

|Let us add two more words here at the beginning of the text.

|Let us add two more words here at the beginning of the text.

|-

|-

|'''Hello and welcome to Bash learning'''

|'''Hello and welcome to Bash learning'''

|-

|-

|  Click on''' Save.'''

|  Click on''' Save.'''

|-

|-

|Let us execute the program again.

|Let us execute the program again.

|-

|-

|  On the '''terminal, type '''dot slash here dot sh'''

|  On the '''terminal, type '''dot slash here dot sh'''

|-

|-

|Press '''Enter.'''

|Press '''Enter.'''

|-

|-

|  Now the output is '''6 '''because we added two more words to our text.

|  Now the output is '''6 '''because we added two more words to our text.

|-

|-

|  We can also pass an argument to the '''Here document.'''

|  We can also pass an argument to the '''Here document.'''

|-

|-

|  Let us see how to do this with an example.

|  Let us see how to do this with an example.

|-

|-

|Let me open a file named '''hereoutput dot sh'''

|Let me open a file named '''hereoutput dot sh'''

|-

|-

|  The command '''cat''' will concatenate files and print the standard output.

|  The command '''cat''' will concatenate files and print the standard output.

|-

|-

|  Note that we have used the string '''this''' instead of '''HERE.'''

|  Note that we have used the string '''this''' instead of '''HERE.'''

|-

|-

|It’s not necessary that you always have to use the delimiter '''HERE'''.  

|It’s not necessary that you always have to use the delimiter '''HERE'''.  

|-

|-

|You can use any other delimiter also.

|You can use any other delimiter also.

|-

|-

|  This line will display the '''0th (zeroeth) argument'''.

|  This line will display the '''0th (zeroeth) argument'''.

|-

|-

|The '''0th (zeroeth) argument''', by default, is the '''filename'''.

|The '''0th (zeroeth) argument''', by default, is the '''filename'''.

|-

|-

|  This line will display the '''1st argument''' passed to the program.

|  This line will display the '''1st argument''' passed to the program.

|-

|-

|  And this line will display the '''2nd argument''' passed to the program.

|  And this line will display the '''2nd argument''' passed to the program.

|-

|-

|  Here we have to close the document using the same delimiter, '''this.'''

|  Here we have to close the document using the same delimiter, '''this.'''

|-

|-

|  Save the file.

|  Save the file.

|-

|-

|  Let us now execute the program.

|  Let us now execute the program.

|-

|-

|On the '''terminal''' type: '''chmod space plus x space hereoutput dot sh'''

|On the '''terminal''' type: '''chmod space plus x space hereoutput dot sh'''

|-

|-

|Press '''Enter'''

|Press '''Enter'''

|-

|-

|Type '''dot slash hereoutput dot sh space Sunday space Monday'''

|Type '''dot slash hereoutput dot sh space Sunday space Monday'''

|-

|-

|  The output is dispalyed as:

|  The output is dispalyed as:

|-

|-

|'''0'th argument is: dot salsh hereoutput dot sh ''' which is the '''filename.'''

|'''0'th argument is: dot salsh hereoutput dot sh ''' which is the '''filename.'''

|-

|-

|'''1st argument is: Sunday'''

|'''1st argument is: Sunday'''

|-

|-

|'''2nd argument is: Monday '''

|'''2nd argument is: Monday '''

|-

|-

|  Let us learn about '''Here string''' now.

|  Let us learn about '''Here string''' now.

|-

|-

|* '''Here string '''is used for input redirection from text or a variable.

|* '''Here string '''is used for input redirection from text or a variable.

|-

|-

|* The input is mentioned in the same line within single quotes.

|* The input is mentioned in the same line within single quotes.

|-

|-

|  The syntax is, '''command space three less than symbols space''' within single quotes write '''string'''

|  The syntax is, '''command space three less than symbols space''' within single quotes write '''string'''

|-

|-

|  Let us understand this with an example.  

|  Let us understand this with an example.  

|-

|-

|I will open the same file '''here dot sh'''

|I will open the same file '''here dot sh'''

|-

|-

|  Here at the end, I will type: '''wc space hyphen w three less than symbols space''' within single quotes '''Welcome to Bash learning'''

|  Here at the end, I will type: '''wc space hyphen w three less than symbols space''' within single quotes '''Welcome to Bash learning'''

|-

|-

|This will redirect the string within quotes to the command '''wc hyphen w.'''

|This will redirect the string within quotes to the command '''wc hyphen w.'''

|-

|-

|Now Click on '''Save '''to save the changes.

|Now Click on '''Save '''to save the changes.

|-

|-

|  We will switch to the '''Terminal.'''

|  We will switch to the '''Terminal.'''

|-

|-

|  Now type: '''dot slash here dot sh'''

|  Now type: '''dot slash here dot sh'''

|-

|-

|  We can see the output as '''6''' and '''4'''

|  We can see the output as '''6''' and '''4'''

|-

|-

|Number of words in '''here document''' is '''6''' and number of words in '''here string''' is''' 4.'''

|Number of words in '''here document''' is '''6''' and number of words in '''here string''' is''' 4.'''

|-

|-

|  Likewise, you can write your own '''Here strings.'''

|  Likewise, you can write your own '''Here strings.'''

|-

|-

|  This brings us to the end of this tutorial.

|  This brings us to the end of this tutorial.

|-

|-

|Let us summarise.  

|Let us summarise.  

|-

|-

|In this tutorial we learnt about

|In this tutorial we learnt about

|-

|-

|* '''HERE document'''

|* '''HERE document'''

|-

|-

|* '''HERE string'''  

|* '''HERE string'''  

|-

|-

|  As an assignment, convert a string to uppercase using:

|  As an assignment, convert a string to uppercase using:

|-

|-

|* '''Here document'''

|* '''Here document'''

|-

|-

|* '''Here string'''

|* '''Here string'''

|-

|-

|Hint:''' tr space  a hyphen z space capital A hyphen capital Z'''.

|Hint:''' tr space  a hyphen z space capital A hyphen capital Z'''.

|-

|-

|This is the command to convert characters from lower to upper case.

|This is the command to convert characters from lower to upper case.

|-

|-

|  Watch the video available at the link shown below.

|  Watch the video available at the link shown below.

|-

|-

|It summarises the Spoken Tutorial project.

|It summarises the Spoken Tutorial project.

|-

|-

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

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

|-

|-

|  The Spoken Tutorial Project Team  Conducts workshops using spoken tutorials

|  The Spoken Tutorial Project Team  Conducts workshops using spoken tutorials

|-

|-

| Gives certificates to those who pass an online test

| Gives certificates to those who pass an online test

|-

|-

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

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

|-

|-

|  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.

|-

|-

|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.

|-

|-

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

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

|-

|-

|  The script has been contributed by FOSSEE and Spoken-Tutorial teams.

|  The script has been contributed by FOSSEE and Spoken-Tutorial teams.

|-

|-

|This is Ashwini Patil from IIT Bombay. Signing off

|This is Ashwini Patil from IIT Bombay. Signing off

|-

|-

|Thank you for joining.

|Thank you for joining.

|}

|}