Fall 2018 - September to December 2018 - Updated 2018-09-22 22:19 EDT
Do not print this assignment on paper!
- On paper, you will miss updates, corrections, and hints added to the online version.
- On paper, you cannot follow any of the hyperlink URLs that lead you to hints and course notes relevant to answering a question.
- On paper, scrolling text boxes will be cut off and not print properly.
23h59 (11:59pm) Friday September 28, 2018 (end of Week 4)
Do not print this assignment on paper! On paper, you cannot follow any of the hyperlink URLs that lead you to hints and course notes relevant to answering a question.
This assignment is based on your weekly Class Notes.
man
command, and use the less
pagination program.Remember to READ ALL THE WORDS to work effectively and not waste time.
This is an overview of how you are expected to complete this assignment. Read all the words before you start working.
For full marks, follow these directions exactly.
You will create file system structure in your CLS home directory containing various directories and files. You can use the Checking Program to check your work as you do the tasks. You can check your work with the Checking Program as often as you like before you submit your final mark.
Some task sections below require you to finish the whole section before running the Checking Program; you may not always be able to run the Checking Program successfully after every single task step.
When you are finished the tasks, leave the files and directories in place on the CLS as part of your deliverables. Do not delete any assignment work until after the term is over!
Assignments may be re-marked at any time on the CLS; you must have your term work available on the CLS right until term end.
Since I also do manual marking of student assignments, your final mark may not be the same as the mark submitted using the current version of the Checking Program. I do not guarantee that any version of the Checking Program will find all the errors in your work. Complete your assignments according to the specifications, not according to the incomplete set of the mistakes detected by the Checking Program.
All references to the Source Directory below are to the CLS directory ~idallen/cst8207/18f/assignment02/
and that name starts with a tilde character ~
followed by a user name with no intervening slash. The leading tilde indicates to the shell that the pathname starts with the HOME directory of the account idallen
(seven letters).
You do not have permission to list the names of all the files in the Source Directory, but you can access any files whose names you already know.
First, you must log in remotely to the Course Linux Server. Most system admin work is done via remote log-in like this; you are rarely sitting in front of the machine you are administering.
See Remote Login for the background you need to read the document Course Linux Server.
Your instructor will demonstrate logging in to the Course Linux Server and the commands below and File Transfer in your lab periods in the first two weeks of school. Read the notes and attend any lab period for further assistance.
Keep notes for every command name used in this course, giving its name, an explanation of what it does, and a short example. Quizzes and tests will require you to remember these command names. A List of Commands is available each week.
PuTTY
on Windows, or Terminal
with ssh
on Mac OSX).
The CLS is on the public Internet; security is important. Choose your password carefully, or else Internet attackers will break into the CLS through your account. Don’t let this happen!
Read on Wikipedia: Guidelines for strong passwords
Read this XKCD comic on good passwords
Now RTFM in the Manual for the Linux command named passwd
(note the odd spelling). No arguments or options are needed to this command to change your own password.
Change your CLS 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.
Accounts that do not have their passwords changed before the due date of this assignment will be disabled.
This task shows you some simple Linux command lines that were introduced in class and lab. It also demonstrates file Output Redirection using the >
character, where you can save the output of a Linux command line in a file instead of having the output display on your screen.
All of these Linux command names have manual pages – man
pages – and you can read the manual page for a command by using the man
command followed by the name of the command, e.g. man date
or man users
As you did in class, try each of the Linux command lines below at the bash
shell prompt on the CLS. Do not type the leading dollar ($
) prompt character. Only type the command name and any arguments to the command, separated by spaces as you see below.
$
) after you enter a command and push Enter
, try typing ^C
(CTRL-C
– hold down the Ctrl
key and type the letter C
at the same time) to interrupt the command and get the bash
dollar prompt back. This is described in Interrupting Programs with ^C
.rm
command, e.g. rm cal.txt
would remove the cal.txt
file.$ date
$ users
$ who
$ echo Hello World
$ cal 9 1752
$ figlet Hello World
$ toilet Hello World
$ history
cal
with the year or month and year you were born, e.g. cal 1954
or cal 7 1954
fortune
, sl
, and cmatrix -s
Create a file named date.txt
on the CLS as follows: Use shell file Output Redirection to save the output of the date
command into an output file by adding to the right end of the command line a space, the right angle-bracket redirection character >
, and then an output file named date.txt
on the command line, like this:
$ date >date.txt
Note the space between the command name date
and the added redirection syntax that uses the right angle bracket. You can add redirection syntax to most any Unix/Linux command line.
Removing files: You can remove (delete) any file you create by using the rm
command, e.g. rm date.txt
would remove the date.txt
file. (Did you write this command in your notebook of Linux commands?)
The command ls
shows the names of files in your account, and it should show you the name of the date.txt
file you just created. You can use the -l
option (it’s a dash followed by a letter, not a digit) to get more information about files, like this:
$ ls
$ ls -l
$ ls -l date.txt
Use the above three command lines and note how the output differs. (Did you write this command and option in your notebook of Linux commands?)
The file
command takes one or more pathname arguments and tells you what type of thing each name is. Use the command to show the type of the date.txt
file you just created and see that it is an ASCII text file. You can try other pathnames, too. Here are examples of commands and their output; try all of them yourself:
$ file date.txt
date.txt: ASCII text
$ file /dev/null
/dev/null: character special (1/3)
$ file /
/: directory
$ file .
.: directory
Try each of the above command lines and make sure you see the same output on your screen. (Did you write this command name in your notebook of Linux commands?)
The command cat
displays the contents of a file on your screen:
$ cat date.txt
Use the above command line to display on your screen the contents of the date.txt
file you created earlier using Output Redirection. (If you get an error No such file or directory, check your spelling.)
We can repeat the same sequence of commands with most any Unix/Linux command. We could redirect the output of the echo
command into a file named foo
, show the properties of the file, and then show the contents of the file:
$ echo Hello World
Hello World # output appears on your screen
$ echo Hello World >foo # output goes into the file foo
$ ls -l foo # use ls command to show file size, date information
-rw-rw-r-- 1 abcd0001 abcd0001 12 Jan 15 05:12 foo
$ file foo # use file command to show the type of the file
foo: ASCII text
$ cat foo # display file contents on screen
Hello World
Using the left angle-bracket >
followed by a file name allows you to redirect or save the output of almost any Linux command into any file name. This is called Output Redirection. We will cover redirection in more detail later in the course.
Re-do all of the simple Linux commands that you used at the start of this task, exactly as you used each above, with the same command arguments, redirecting the output of each of the commands into a file that is the name of the command with a .txt
extension added. Use the same command arguments as given above. View the file contents after each command. It will look like this:
$ date >date.txt
$ cat date.txt
$ echo Hello World >echo.txt
$ cat echo.txt
Repeat for all of the commands used at the start of this task. The output file name uses the name of the command (not including any arguments to the command). Leave these output files (corresponding to the command names) in your account on the CLS.
The syntax and format of each command line is described in Typing Command Lines and Basic Command Line Syntax. Read those pages to know how to distinguish a command name from command arguments. Your output file names must use only the command name not the command arguments.
Run the Checking Program to verify your work so far.
Your instructor will walk you through File Transfer in your lab period. Come to any lab period for assistance in making this work for you.
Do a practice File Transfer, fetching a file from the CLS to your local machine (e.g. to your local Windows or OSX laptop), like this:
First, create a file linux.txt
on the Linux CLS containing some calendar output. You can create this file using file output redirection, as you did above. Use ls
to see the file name and cat
to see the content of the linux.txt
file, as you did above. Make sure the file is not empty!
Transfer the above linux.txt
file from the Linux CLS to your local machine using the instructions in the page File Transfer.
WinSCP
or Filezilla
program for Windows, or use a Terminal
with the scp
command for Mac OSX.After you transfer the linux.txt
file from the CLS to your local machine, open the transferred file on your local machine.
You must know how to redirect program output into a file and transfer that file from the CLS to your local machine to be able to submit the output of the Checking Program to Brightspace for marking.
man
commandIndexYou need to know RTFM in the Manual to do this task, especially the section on Reading manual pages SYNOPSIS Line(s).
There are no electronic deliverables for this task, but your instructor may ask you in the lab about the answers to the five questions in the above RTFM page relating to the SYNOPSIS section of a manual page.
Be ready with any of the five answers, and show that you know how to search for text inside manual pages (inside the less
program).
That is all the tasks you need to do.
Check your work a final time using the Checking Program below and save the standard output of that program into a file as described below. Submit that file (and only that one file) to Brightspace following the directions below.
Your instructor will also mark the files in your account on the due date. Leave everything there on the CLS. Do not delete anything.
When you are done, log out of the CLS before you close your laptop or close the PuTTY window, by using the shell exit
command:
$ exit
Nothing seriously bad will happen if you forget to log out, but you may leave behind an empty, “ghost” login session that may take some days to time out and disappear. Always exit
before you close your laptop, PuTTY, or Terminal session.
Summary: Do some tasks in this Assignment, then run the Checking Program to verify your work as you go. You can run the Checking Program as often as you want. When you are done the assignment or have the best mark you can get, save the output of the Checking Program into a file using output redirection and then upload that one output file to Brightspace for marking.
Since I also do manual marking of student assignments, your final mark may not be the same as the mark submitted using the current version of the Checking Program. I do not guarantee that any version of the Checking Program will find all the errors in your work. Complete your assignments according to the specifications, not according to the incomplete set of the mistakes detected by the Checking Program.
There is a Checking Program named assignment02check
in the Source Directory on the CLS. You can execute this program by typing its (long) pathname into the shell as a command name:
$ ~idallen/cst8207/18f/assignment02/assignment02check
Note the leading tilde ~
character on the command name. Do not type the dollar sign prompt. Use the Enter key at the end of the line. You will learn of ways to make this long line shorter in future assignments.
Execute the above Checking Program as a command line on the CLS. This program will check your work, assign you a mark, and display the output on your screen. The output will be long and will scroll off the top of your terminal window. You can probably use the PAGE UP
key to see the scrolled text.
You may run the Checking Program as many times as you wish, allowing you to correct mistakes and get the best assignment mark.
When you are done with this assignment, and you like the mark displayed on your screen by the Checking Program, you must redirect only the standard output of the Checking Program into the text file assignment02.txt
in your Base Directory on the CLS, like this:
$ ~idallen/cst8207/18f/assignment02/assignment02check >assignment02.txt
assignment02.txt
file name.You can view the output file one-page-at-a-time using the less
program (use the space bar to page forward and use the letter q
to quit):
$ less assignment02.txt
less
use the space bar to page forward and use the letter q
to quit).YOUR MARK for
Transfer the above single file assignment02.txt
(containing the output from the Checking Program) from the CLS to your local computer.
YOUR MARK for
Upload the single assignment02.txt
file from your local computer to the correct A-02 Assignment #02 area on Brightspace before the due date.
assignment02.txt
name.Your instructor may also mark files in your directory in your CLS account after the due date. Leave everything there on the CLS. Do not delete any assignment work from the CLS until after the term is over!
Notes:
I do not accept any assignment submissions by EMail. Use only the Brightspace Upload and Submit method.
Use the exact file name given above. Upload only one single file of output from the Checking Program.
No marks are awarded for submitting under the wrong assignment number or for using the wrong file name. Use the exact 16-character, lower-case name given above.
WARNING: Some inattentive students don’t Read All The Words. Don’t make that mistake! Be exact.
READ ALL THE WORDS. OH PLEASE, PLEASE, PLEASE READ ALL THE WORDS!