Joe Chung
Monmouth U. Homepage

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===== CS 370 List of Assignments =====

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==== Collection Setup ====

During the semester, I will collect your homework and projects from your school UNIX home directory.

After logging into a lab machine or [[http://rockhopper.monmouth.edu/cshelp/Mucsremote|server]], create either a cs370 or se370 directory inside your home directory (~) by running the command:

  mkdir ~/cs370

or

  mkdir ~/se370

Then run either of the following commands:

  submit.cs370

or

  submit.se370

The ''submit...'' command should be run after you add any new files or directories under your ''cs370'' or ''se370'' subdirectory. This will make your class directory available to me; they will not be accessible to other students.

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==== Assignment 1 ====

Deadline: Mon, May 27, 11:59pm

Setup: You will need to access your UNIX account.  Create the ''assignments/1/'' directory **inside** your course directory (''cs370'' or ''se370'').

1. 

A key principle of UNIX design is that [[https://www.informit.com/articles/article.aspx?p=424451&seqNum=2 | everything is (or should be) text]]. See p. 17 of the textbook (//Determining a File's Type with file// and //What is "Text"?//). Identify an ASCII text file in your home directory (not one that you created or modified), and copy that file into the ''assignments/1/'' directory. Note: The ''ls -a'' command finds hidden files.

2. 

See pp. 34-41 of the textbook. To learn basic UNIX file management commands, run all the commands given in the //"Let's Build A Playground"// exercise. To prove that you have gone through the entire exercise, run

  history -w playground_history

to write your shell command history to the file ''playground_history'', and then copy ''playground_history'' into the ''assignments/1/'' directory.

3. 

[[https://cssegit.monmouth.edu/cshelp/csseremote/-/wikis/MUCSremote | Login]] to the ''plato.monmouth.edu'' server (A.K.A. ''aristotleii''). Leave a trace of your visit in the ''/tmp'' directory of ''plato'', i.e., create a small file in the ''/tmp'' directory before you log out. The filename must contain your student id.

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==== Assignment 2 ====

Deadline: Tue, Jun 4, 11:59pm

Setup: You will need to access your school Unix account.  Create the ''assignments/2/'' directory **inside** your course directory (''cs370'' or ''se370'').

Write your name, student ID and your answers in the plain text file ''asn2.txt''. **Number each answer.** Save ''asn2.txt'' in the directory for Assignment 2. Note: Some questions require you to create an additional file or symbolic link in the Assignment 2 directory.

1.

Include the hostname of the Linux machine you are using for this question. Does the ''nano'' editor have undo/redo functionality? If it does, how do you use it? How did you figure it out?

2. 

Backup your shell config (''~/.bashrc'') using ''cp''. The backup copy must have the name ''.bashrc.bak''. Copy ''.bashrc.bak'' to the directory for Assignment 2.

3. 

If you have not generated a [[cs370/cs_370_-_introduction_unix_fundamentals#secure_shell_ssh|SSH key pair]] in your UNIX account, do so now. Create a **valid** symbolic link to your ssh **public** key file (**not** the private key file) in the directory for Assignment 2. (See the book, page 38.) 

4. 

How can you use ''ls'' without any colorization of output? How did you find the correct ''ls'' command line option?

5. 

Commands such as ''ls'', ''cp'', ''mkdir'', ''mv'', ''rm'' and ''ps'' have a command line option that shows command usage and a listing and description of all command options. What is that command line option? (See the book, chapter 5.) 

6. 

Say that your present working directory is

  /usr/local/src/system/unison-2.48.3/uimac14/Frameworks/Growl.framework/Versions/Current/Resources

What is the easiest (shortest) way to change to the directory

  /usr/local/src/system/unison-2.48.3/uimac14/Frameworks/Growl.framework/Versions

? (See the book, chapter 2.)

7. 

Say that you have defined the alias

  alias confshell='nano ~/.bashrc'

In that alias, is ''~/.bashrc'' an absolute or relative pathname?

Why is it a good idea to use ''~/.bashrc'' instead of just ''.bashrc'' with this alias? (See the book, chapter 2.) 

8. 

My ''~/.bashrc'' file has the following lines in it

  # Commands to run with every new shell (jchung, 9/2017)
  echo; fortune 2> /dev/null
  
What would be the purpose of ending the ''fortune'' command with ''2> /dev/null''. (See the book, chapter 6.)

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==== Assignment 3 ====

Deadline: Thu, Jun 20, 11:59pm

Setup: You will need to access your UNIX account.  Create the ''assignments/3/'' directory **inside** your course directory (''cs370'' or ''se370'').

Write your name, student ID and your answers (where applicable) in the plain text file ''asn3.txt''. Number each answer. Save ''asn3.txt'' in the directory for Assignment 3. Note: Some questions require you to copy a file into your Assignment 3 directory.

1. 

How can ''grep'' be used to see if a text pattern exists in a shell variable? For example, say that the variable ''$LANGUAGE'' can contain the name of some language. How could grep be used to check if ''$LANGUAGE'' contains "portugese"?

2. 

The ''fortune'' command has an option that allows searching for fortunes that match a text or regular expression pattern. How can ''fortune'' be run to find all fortunes that contain the word "bulwer", ignoring case? How do you use ''grep'' and ''wc'' to count the number of fortunes that contain the word "bulwer"?

3. 

(See chapter 13 of the book.) The ''$HOSTNAME'' environment variable contains the hostname of the Unix system that you are logged into. Write an ''if'' or ''case'' structure that changes the color of your command prompt ''$PS1'' depending on which host you are logged into. Use the following table:

<code>
        Hostname	Color in PS1
        --------        ------------
        rockhopper	Light Gray
        aristotleii	Light Blue
        all others	Green
</code>

Your ''$PS1'' environment var must continue to show your ''userid@hostname'' and ''pwd'' (present working directory), but with added color.

Add the ''if'' or ''case'' structure to your ''~/.bashrc''. Copy your modified ''~/.bashrc'' to your Assignment 3 directory. The modified ''~/.bashrc'' is your answer for question 3.

4. 

Modify the script in the ''for'' structure [[cs370/cs_370_-_shell_scripting#the_for_structure|Example 3 (ping-hh305.sh script)]] so that the script's only output consists of machines in HH305 that do not respond to a ping. Example script output:

<code>
      HH305-19ML65677 not responding
      HH305-18ML65676 not responding
      HH305-17ML65675 not responding
</code>

Notes: In the modified ''ping-hh305.sh'' script, suppress all output (stdout & stderr) from ''ping''. Use the ''ping'' exit status (''$?''). Use an ''if'' statement or conditional chaining. Copy your modified ''ping-hh305.sh'' script into your Assignment 3 directory.

5. 

Complete the [[cs_370_-_text_processing_utilities?&#roster_processing|roster processing exercise]], without using //awk//. Write your new pipeline as your answer.

6. 

How can the ''[[cs_370_-_shell_scripting#the_for_structure|seq]]'' command be used in a command substitution to make the variable ''$list_of_hostnums'' contain

  01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

?

See the ''%%--help%%'' command line option or the ''seq'' command's manual page.

7. 

Write the definition of a shell function called ''anticaps'' that takes a string as an argument and converts all but the first character to lower case. The function would work as follows:

  anticaps "BUZZFEED"
  
  Output: Buzzfeed

Use the ''cut'' and ''tr'' text processing utilities in your function definition. You may also use [[https://mywiki.wooledge.org/BashFAQ/073|parameter expansion]] as an alternative to ''cut''.

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