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questions unix, help using putty. **please show work using a program** with all

ID: 3733632 • Letter: Q

Question

questions unix, help using putty. **please show work using a program** with all questions answered (if possible), I'll rate. so I can Have a understanding really helps

Commands to study to answer this question: tail, head, cmp, diff, comm, uniq, touch,

        umask, grep, vi, cat, ls, and echo

Two files can be compared using cmp command and diff command depending on requirements.

In order to do this question, create two files with 12 or more names with one name in each line. Make sure that some names in the two files are same and some are different. Ensure that there are few consecutive lines with identical names (duplicate lines) in each file. Also, make sure that some of the names are the same in both files.

Create these two files before issuing the script command to answer this question.

1) Display the content of each file, one at a time

2) Compare the two files using cmp command

3) Find the differences between using diff command

4) Sort first file and store the result by redirecting the output to a file as sorted

5) Sort second file and store the result by redirecting the output to another file as sorted

Two files can also be compared comm command. There are differences between cmp, diff and comm commands. Read about them and understand the differences.

6) Compare the two sorted files using comm command

7) Display ONLY the bottom 5 lines of the first file

8) Display the top few lines of the second file using the default line count, that is, without using any option in the command. Count and find how many lines it displays by default

9) Issue appropriate command to display the content of first file removing consecutive duplicate lines

10) Create the file hw2before_setting_umask using touchcommand

11) The umask command can be used to set or change the default file permissions to be set when a new file is created. Issue umask 600 command

12) Create the file hw2after_setting_umask using touchcommand

13) Display the file permissions set on hw2before_setting_umask and hw2after_setting_umask

14) Using echo command answer what permissions were removed for the owner due to the above umask command

The grep command can be used to search for a string in one or more files. When the line with the string is found, it is displayed. Check this by issuing the following grep commands.

15) Issue a grep command on hw2test1 with a name that exists in hw2test1.

16) Issue a grep command on hw2test[12] with a name that exists in both files (hw2test1 and hw2test2).

17) Issue a grep command on hw2test[12] with a name that does not exist in both files.

18) What difference you see between (16) and (17) by Observing the output of above three grep commands

Explanation / Answer

Two names Txt files:

f1.txt:

Hello

World

Loren

Pierre

Edward

Lakme

Reli

Danny

Justin

Justin

David

Query

Mary

f2.txt:

Ram

Sita

Hari

Justin

Mary

Mary

Query

Hello

Different

Oswald

Doremon

Pokemon

HaoYang

Donald

1. "cat f1.txt" for displaying file f1.txt

"cat f2.txt" for displaying file f2.txt

cat f1.txt f2.txt for displaying files together.

2. cmp f1.txt f2.txt for comparing two files

3. diff f1.txt f2.txt for finding the difference between two files

4. sort f1.txt > sortedf1.txt for sorting the file and storing the content into file named as "sortedf1.txt"

5. sort f2.txt > sortedf2.txt for sorting the file and storing the content into file named as "sortedf2.txt"

Differences between cmp, diff, comm

cmp: Compare files byte by byte. Gives the output as difference found at line and character number.

diff: Compare files line by line. Gives the output as the lines which differ in files

comm: The comm utility reads file1 and file2, which should be sorted lexically and produces three text columns as output: lines only in file1; lines only in file2; and lines in both files.

6. comm sortedf1.txt sortedf2.txt compares two sorted files and gives the differences and comman things.

7. tail -n 5 f1.txt" or tail -5 f1.txt Displays last five lines of f1.txt

8. head f2.txt Displays default top 10 lines of file f2.txt

9. uniq f1.txt Displays only unique lines present in file. Removes duplicated lines.

10. touch hw2before_setting_umask

11. umask 600

12. touch hw2after_setting_umask

13. ls -l hw2before_setting_umask hw2after_setting_umask displays file permissions in first column

15. grep Hello f1.txt

16. grep Justin f[12].txt

17. grep James f[12].txt

18. The difference between the outputs is that, in 16th command we see the file names along with the word present in those files. While in 17th command we don't find any output. It simply exits.

NOTE: Please rename the file names f1.txt to hw2test1.txt and f2.txt to hw2test2.txt and run all the commands for renamed files.