CMSC216 Discovery Exercise 1 (Covers Chapters 1)

Discovery Exercises Chapter1

1, Use the whatis command to determine the purpose of the ls command.

2, Use the man program to find out what the -R option does when used with the date command.

3, Use the man program to determine what other commands you should also see in relation to the clear command

4, Use the cal command to determine on what day of the week you were born.

5, Use the cal command to determine which year between 2005 and 2010 is a leap year.

6, Clear the screen, and view the online manual to determine how to display todays date in UTC.

7, Display the current UTC.

8, Create a file called month containing the current month

9, View the contents of the month file you created in Exercise 8.

10, Use the who command to determine the idle time for users currently logged in, but output that information to a file called users_info. Next view the file you created.

11, View the files, month and users_info, in sequence using only one command-line sequence of commands

12, View the files month and users_info in sequence by using:

The less command

The more command

13, Create a file called who_info that contains the documentation for the who command. Next, use the less command to view the who_info file contents and scroll forward and backward through the information. Then use the tail command to view the final 12 lines of the who_info file. Finally, use the head command to view the first 12 lines of the who_info file.

14, Create a file called favorite_foods, and list your favorite foods, entering five or six or more. Press Enter after each favorite food so it appears on its own line (make certain you also press Enter after the final food item). After the file is created, add two more foods you like that are not on the list (press Enter after the final food item). View the list of foods to make certain the two items you added appear at the end of the list.

15, View the documentation for who and then view the documentation for w. How are these commands similar?.

16, Run the who -uH and w commands using one command-line sequence to compare the results.

17, Determine when the computer you are working on was last booted.

18, Use the command-line history function to determine the most recent two commands you entered.

19, Run the who -H, cal 2009,, and clear commands using one command-line sequence. What do you end up with on the screen?

20, Use the history function to retrieve the command line you used in Exercise 19. Use the edit function to remove the word clear and replace it with date. Next, go to the beginning of cal and delete the text on the line from cal to the end. Now, change the -H to -u. Finally, add ; date -u so that your final command-line entry is: who -u ; date -u. Execute the command-line entries.