Friday 4 May 2012

UNIX ASSIGNMENT 2

1. Create a tree structure named ‘training’ in which there are 3 subdirectories – ‘level 1’,’ level2’ and ‘cep’. Each one is again further divided into 3. The ‘level 1’ is divided into ‘sdp’, ‘re’ and ‘se’. From the subdirectory ‘se’ how can one reach the home directory in one step and also how to navigate to the subdirectory ‘sdp’ in one step? Give the commands, which do the above actions?
Ans : To navigate from 'se' to home directory,in one step,the command is : cd
          To navigate from 'se' to 'sdp',in one step,the command is : cd ../b

2. How will you copy a directory structure dir1 to dir2 ? (with all the subdirectories)
Ans : cp –R dir1 dir2

3. How can you find out if you have the permission to send a message?
Ans : ls -l ( To check access permissions)

4. Find the space occupied ( in Bytes) by the /home directory including all its subdirectories.
Ans : du -s -b


5. What is the command for printing the current time in 24-hour format?
Ans : date +%T

6. What is the command for printing the year, month, and date with a horizontal tab between the fields?
Ans : date +%Y%t%B%t%e

7. Create the following files: chapa, chapb, chapc, chapd, chape, chapA, chapB, chapC, chapD, chapE, chap01, chap02, chap03, chap04, chap05, chap11, chap12, chap13, chap14, and chap15.
Ans :The general syntax is :
   cat > filename
    Type the contents of file
    Press Ctrl+D

1.      cat > chapa
           Type the contents of file
            Ctrl+D

2.        Cat > chapb
             Type the contents of file
             Ctrl+D


3.       Cat > chapc
         Type the contents of file
          Ctrl+D

4.      Cat > chapd
Type the contents of file
Ctrl+D

5.     Cat > chape
Type the contents of file
Ctrl+D

6.     Cat > chapA
Type the contents of file
Ctrl+D

7.     Cat > chapB
Type the contents of file
Ctrl+D

8.     Cat > chapC
Type the contents of file
Ctrl+D

9.     Cat > chapD
Type the contents of file
Ctrl+D

10.                         Cat > chapE
Type the contents of file
Ctrl+D

11.                         Cat > chap01
Type the contents of file
Ctrl+D

12.                          Cat > chap02
Type the contents of file
Ctrl+D

13.                         Cat > chap03
Type the contents of file
Ctrl+D



14.                         Cat > chap04
 Type the contents of file
Ctrl+D

15.                         Cat > chap05
Type the contents of file
Ctrl+D

16.                         Cat > chap11
Type the contents of file
Ctrl+D

17.                        Cat > chap12
Type the contents of file
Ctrl+D

18.                         Cat > chap13
Type the contents of file
Ctrl+D

19.                        Cat > chap14
Type the contents of file
Ctrl+D

20.                         Cat> chap15
Type the contents of file
Ctrl+D


8. With reference to question 7, What is the command for listing all files ending in small letters?
Ans : find –name “*[a-z].*”

9. With reference to question 7, What is the command for listing all files ending in capitals?
Ans : find –name “*[A-Z].*”

10. With reference to question 7, What is the command for listing all files whose last but one character is 0?
Ans : find –name “*0?.*”

11. With reference to question 7, What is the command for listing all files which end in small letters but not ‘a’ and ‘c’?
Ans: find –name “*[b d-z].*”

12. In an organisation one wants to know how many programmers are there. The employee data is stored in a file called ‘personnel’ with one record per employee. Every record has field for designation. How can grep be used for this purpose?
Ans : grep -c "programmers" personnel

13. In the organisation mentioned in question 12 how can sed be used to print only the records of all employees who are programmers.
Ans : sed -n /programmers/p personnel

14. In the organisation mentioned in question 12 how can sed be used to change the designation ‘programmer’ to ‘software professional’ every where in the ‘personnel’ file
Ans :  sed 's/programmer/software professional/g' personnel

15. Find out about the sleep command and start five jobs in the background, each one sleeping for 10 minutes.
Ans :sleep 10m & sleep 10m & sleep 10m & sleep 10m & sleep 10m &

16. How do you get the status of all the processes running on the system? i.e. using what option?
Ans : ps -e


No comments: