5.1 The Source DirectoryIndex

All references to the “Source Directory” below are to the directory
~idallen/cst8207/13w/assignment02/  and that name starts with a tilde character “~” followed by a userid with no intervening slash. The leading tilde indicates to the shell that the pathname starts with the HOME directory of the account idallen.

5.2 Label all your hardwareIndex

1. Put your name and contact information on all your books and hardware, including your external hard disks and power supplies. The name has to be clear enough that the office can contact you to give you back your hardware when you leave it behind somewhere.

5.3 Worksheet and PromptIndex

This worksheet prepares you to do the numbered tasks listed below by executing commands while logged in remotely to the Course Linux Server.

You can download Libre Office (or Open Office) for Windows to edit the Worksheet *.odt files and save your answers. (Or you can print the PDF and write your answers on paper.) Save your answers for quizzes!

2. Use LibreOffice or OpenOffice to open, complete, and save: Lab Worksheet #02 ODT
   • Do not use MSWord to open this file; it damages the file.
   • You will find it easier to write over the red underscores using “OVERWRITE” typing mode instead of the default “INSERT” mode.
   • Another way to fill in answers is to double-click to select the entire line of underscores and then simply type or paste to replace it.
   • Quizzes will ask you about your answers in your saved worksheets.
   • Read All The Words
3. Using the PS1 variable syntax shown in Lab Worksheet #02 HTML, set your prompt to include your user name, your computer name, and the basename of your current working directory. (See the definition of basename in the Pathnames class notes.)
   • The prompt will look similar to this:   [abcd0001@idallen-ubuntu ~]$

Set your prompt every time you log in to the CLS, so that the prompt changes to tell you you the basename of your current working directory. This is faster than typing pwd all the time!

5.4 Security - Change your CLS passwordIndex

The CLS is on the public Internet; security is important. Choose your password carefully. Accounts that do not have their passwords changed before the due date of this assignment will be disabled.

4. Read “Guidelines for strong passwords” in http://en.wikipedia.org/wiki/Password_strength#Guidelines_for_strong_passwords

5. Now read this XKCD comic: http://xkcd.com/936/

6. Now RTFM for the Unix command named “passwd” (note the spelling). No arguments or options are needed to change your own password. The passwd command is also described in Lab Worksheet #02 HTML.

7. Change your password to one that is more secure than the one you were given. Find a way to remember your new password. If you forget your password, contact your Linux instructor to have it reset.

5.5 Creating new directories and filesIndex

8. Create the following directory structure in your CLS HOME directory and record (for study purposes) the series of Unix commands you used to create it. Spelling and capitalization must be exactly as shown:

   CST8207-13W/
   `-- Assignments
       `-- assignment02
           `-- tree
               |-- one
               |   `-- oneone
               `-- two
                   `-- twotwo

   • The “CST8207-13W” directory is created in your CLS HOME directory.
     • The “Assignments” directory is created in the CST8207-13W directory.
       • The “assignment02” directory is created in the Assignments directory.
         • The “tree” directory is created in the assignment02 directory.
           • Under tree are two new directories named “one” and “two”.
             • Under directory one is new directory “oneone”.
             • Under directory two is new directory “twotwo”.

   You can check your work by making your HOME directory your current directory and using one of these commands below. Use the command that gives the best-looking output:

   $ tree CST8207-13W
   $ tree -A CST8207-13W

   The correct output will be similar to the ASCII tree diagram above. The spelling and capitalization must be exactly as shown.

   Note: You can create the entire directory tree above using one single command with one option and two pathname arguments. System administrators like to work efficiently - they learn how to do things quickly.

9. Make the assignment02 directory your current directory and then use a command to recursively generate a list of all pathnames under your tree directory. (You used this command this at the end of Lab Worksheet #02 HTML). The recursive output of all pathnames under your tree directory will be exactly five lines long and will contain this exact line in the output somewhere (along with another four lines):

   tree/one/oneone

Recall that you can redirect any output that appears on your screen into a file by adding to the end of the command line a “greater than” angle bracket followed by a file name. (We did this using the cal command to create the cal.txt file in the Week 2 labs and you can see an example of this up above in the Practice section.)

10. When the recursive output above on your screen looks correct, redirect the output of the command into the file named “paths.txt” in the oneone directory that you created earlier. (Use a relative path down to the oneone directory, as shown in the Week 3 lectures.)

11. Make the oneone directory your current directory. Use a command to list the files in the current directory to confirm that the paths.txt file is here. Use another command to display the contents of the paths.txt file, and make sure it contains at least five lines of pathnames.

12. Copy the paths.txt file (from the current oneone directory) into the twotwo directory that you created earlier, giving it the new name “paths.txt.copy” as you copy it. Again, use relative paths to do the copy, as shown in the Week 3 lectures. (Hint: Draw a file system hierarchy picture to help you derive the correct relative pathname.)

Run the Checking Program to verify your work so far.

5.6 Working with existing directories and filesIndex

13. Execute this exact command line in your account on the CLS:

    $ ~idallen/cst8207/13w/assignment02/create

• There is a leading tilde character “~” directly in front of the account name “idallen”, indicating to the shell that the pathname starts with the HOME directory of idallen.

• The command will create a directory named “stuff” in your assignment02 directory. It will contain some sub-directories and files.

• You can re-execute the above line to start over from scratch, if you make errors in this part of the assignment.

• To know what files and directories have been created by the above command line, use a command that will recursively show all the files and directories under a starting directory. (You already used this command, above.)

All the following commands in this section apply to files and directories under the new stuff directory. You will have to use commands to find some of the file names mentioned here; they may be located under sub-directories. (See Searching and Finding Files.) Some of these tasks may require more than one command to complete.

14. Find and read the file named “README.txt” (somewhere under stuff).

15. Read and then delete the file “foo.txt” that is in the same directory as “README.txt”. (Do not delete any other decoy files named “foo.txt” that may be in different directories.)

16. Move (rename) the file “dst” to be “dst.bak”. (This is a move, not a copy. It renames the file.)

17. Directly under the new “stuff” directory, create a new empty directory named “dst”. (Make sure you create “dst” under stuff, not in your HOME or any other directory.)

18. Find the file named “services” (not the directory with the same name) and move (rename) that “services” file to be named “ports” under the new directory “dst” that you just created. (This is a move/rename, not a copy.) Make sure you move the file, not the directory with the same name.

Run the Checking Program to verify your work so far.

5.7 Finding files in a mazeIndex

19. Under the Source Directory there is a directory named “maze”. This maze contains many hidden sub-directories. (You need a special option to see hidden files and directories.) In this maze, use a single command to recursively find the file with a 12-character basename that looks similar to “abcd0001.txt” but where the eight-character “abcd0001” part of the name is replaced by your own account userid. You must use a single command that finds files by basename to find this 12-character file name. Do not try to use “cd” and “ls” to find the file in the maze; the maze is very big.

20. When you have found your personal “abcd0001.txt” file in the maze, copy your file into the “dst” directory you created above, using the new name “me.txt” under “dst”. Read the file to make sure it’s the right one after you copy it into “dst”.

Run the Checking Program to verify your work so far.

That is all the tasks you need to do. Next, mark your work: