Updated: 2015-03-11 14:28 EDT

1 Due Date and Deliverables

Do not print this assignment on paper!

2 Purpose of this Assignment

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.

  1. Create shell scripts that deal with process management, EMail, crontab, and at.
  2. Practise with a text editor.

3 Introduction and Overview

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.

  1. Complete the Tasks listed below.
  2. Verify your own work before running the Checking Program.
  3. Run the Checking Program to help you find errors.
  4. Submit the output of the Checking Program to Blackboard before the due date.
  5. READ ALL THE WORDS to work effectively and not waste time.

3.1 Save your work

You will create file system structure in your HOME directory on the CLS, with various directories, files, and links. When you are finished the tasks, leave these files, directories, and links in place as part of your deliverables on the CLS. Do not delete any assignment work until after the term is over! Assignments may be re-marked at any time; you must have your term work available right until term end.

3.2 The Source Directory

All references to the Source Directory below are to the CLS directory ~idallen/cst8177/15w/assignment06/ 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.

3.3 Searching the course notes on the CLS

The previous term’s course notes are available on the Internet here: CST8207 GNU/Linux Operating Systems I. All the notes files are also searchable on the CLS. You can recall how to read and search these files using the command line on the CLS under the heading Copies of the CST8207 course notes near the bottom of the page Course Linux Server Course Notes.

3.4 Review of How To Write and Test Scripts

  1. Some of the tasks below ask you to write a small executable shell script, based on the lecture notes and slides. None of the scripts need Boolean expressions (“||” or “&&” or -a or -o); they are all simple scripts with simple conditional logic.

  2. Each script below must begin with the Standard Script Header you used for your previous script assignments. See the class notes.

  3. Some scripts contain simple one-line pipelines. You can first create these pipelines on the command line, get them working correctly, then copy the working pipeline into the script file when it works. It is much faster to test and fix the pipeline on the command line instead of editing and saving the script file over and over.

  4. Though the header is executable code, in the descriptions below we don’t count those lines, or any comment or blank lines, in the size of the script. We only count the new lines of code that you write.

    For example, a “two-line script” is really several lines of header, a blank line, a block of several comment lines that Document Your Script, another blank line, and then your two lines of actual script code. The description below calls this a two line script, even though it may contain a dozen lines.

  5. When you have completed each script, ensure that it is executable, so that it can be executed as ./scriptname.sh from the shell command line.

  6. Run the given tests on your scripts to make sure they work. Sample output for each of the scripts is given, so that you may check your work as you proceed.

  7. Make sure your script handles all of the sample inputs given, especially the inputs containing shell metacharacters. (System crackers often attack your system using special characters as input.)

    Scripts must validate their arguments, even if they take no arguments. (A script that takes no arguments must not run if you give it arguments, since clearly you don’t know how to use it.) Error messages must be written in the style of Good Error Message, as you did in the previous assignment. Always follow the Good Error Message with a Usage message that says how the script should be run.

    Scripts that have usage errors should exit with a non-zero exit code, indicating something went wrong.

  8. The examples below do not fully test your script; you will need to try other examples to make sure your scripts work properly for all possible inputs. Always test your scripts with quoted shell GLOB pattern arguments to make sure they don’t expand inside the script.

  9. When your script is working, Document Your Script as you did in the previous assignment.

4 Tasks

For full marks, follow these task directions below exactly as written. READ ALL THE WORDS to work effectively and not waste your time.

  1. Complete the Tasks listed below, in order, from top to bottom.
  2. Do not skip steps.
  3. These tasks must be done in your account on the Course Linux Server.
  4. Verify your own work before running the Checking Program.
  5. Run the Checking Program to help you find errors and grade your work.
  6. Submit the grading output of the Checking Program to Blackboard before the due date.
  7. Your instructor may also mark on the due date the work you do in your account on the CLS. Leave all your work on the CLS and do not modify it. Do not delete any assignment work from the CLS until after the course is over.

4.1 Set Up – The Base Directory on the CLS

  1. Do a Remote Login to the Course Linux Server (CLS) from any existing computer, using the host name appropriate for whether you are on-campus or off-campus. All work in this assignment must be done on the CLS.

  2. Base Directory: Make the CLS Base Directory named ~/CST8177-15W/Assignments/assignment06, in which you will create the files for the following tasks.

    This CLS assignment06 directory is the Base Directory for most pathnames in this assignment. Store your files and answers in this Base Directory on the CLS.

  3. Create the check symbolic link needed to run the Checking Program, as described in the section Checking Program below.

Use the symbolic link to run the Checking Program to verify your work so far.

Check your work so far using the checking program symlink.

4.2 The Processes Script – process_id.sh

Using the specifications below, write an executable script named process_id.sh that shows information about processes that are owned by a given user name and have a given command name. Use the Hints below to help you.

  1. The process_id.sh script must start with the correct Script Header lines.

  2. The script takes exactly two arguments. The first is the user name of the process owner, and the second is the command name of the processes to show:
    • ./process_id.sh user_name command_name
  3. The script must print zero or more lines containing process information about every process with the given command_name owned by the given user_name (if any).

  4. The script should show only lines for processes owned by the given user_name and with the given command_name.

  5. The script must not show any lines for partial user names such as roo or oot or partial command names such as bas or ash. Both names given by the user must match fully in the output of ps.

  6. The script must print a Good Error Message and Usage message if it doesn’t receive exactly two command line arguments, and exit with an exit status of 2.

  7. The script does not have to validate the user name or produce any error message if no lines of output are generated. Failing to match any processes is not an error.

  8. When your script is working, Document Your Script as you did in the previous assignment.

4.2.1 Examples for process_id.sh

Your output and numbers will differ.

$ ./process_id.sh "$USER" process_id.sh
abcd0001 9170 0.0 0.0 4400 612 pts/2 S+ 10:25 0:00 /bin/sh -u ./process_id.sh abcd0001 process_id.sh
$ ./process_id.sh "$USER" bash
abcd0001 1647 0.0 0.0 26344 2740 pts/2 Ss Oct22 0:00 -bash
$ ./process_id.sh "$USER" sshd
abcd0001 1643 0.0 0.0 90508 1308 ? S Oct22 0:02 sshd: abcd0001@pts/2
$ ./process_id.sh root cron
root 3574 0.0 0.0 19112 860 ? Ss Oct22 0:03 cron
$ ./process_id.sh root sshd | wc -l
10                                          # should find at least two
$ ./process_id.sh oot sshd | wc -l
0                                           # no such user name
$ ./process_id.sh roo sshd | wc -l
0                                           # no such user name
$ ./process_id.sh sshd sshd | wc -l
0                                           # no such user name
$ ./process_id.sh www apache2 | wc -l
0                                           # no such user name
$ ./process_id.sh root s | wc -l
0                                           # no such process name
$ ./process_id.sh sshd root | wc -l
0                                           # no such user or process
$ ./process_id.sh '*' '*' | wc -l
0                                           # no such user or process
$ ./process_id.sh one
./process_id.sh: Expecting two arguments, found 1 (one)
Usage:  ./process_id.sh user_name command_name
$ ./process_id.sh one two three
./process_id.sh: Expecting two arguments, found 3 (one two three)
Usage:  ./process_id.sh user_name command_name

4.2.2 Hints for process_id.sh

  1. The script will use the ps command and a pipeline of one or more commands to select only those ps output lines that match the given user name and command name.

  2. Refer to your previous assignment work on process listings from Assignment #02: Creating a script

  3. The active part of the script will be one line long (a pipeline). A perfect solution needs only two commands separated by one pipe.

  4. That one line will be preceded by code to check the number of arguments (two arguments), plus some lines for the Script Header. As with many one-line scripts, the code needed to check the arguments greatly exceeds the code that does useful work!

  5. Do not use any options to ps that show all processes! You cannot easily search the resulting output for a command name.

  6. Use only the two ps options described next:
    1. The ps command has a useful option to display only processes with a particular command name. Using this option to select only lines that contain that command name makes the script much simpler, since otherwise it is tricky to use grep to match a command name in the middle of a line of ps output. If you don’t use this option to ps you must select the command name carefully by choosing some surrounding context from the output lines using grep. I recommend using the ps option, not grep.
    2. In addition to the option that selects command name, you will need an option to make ps generate a user name at the start of every output line. See the man page for either the full-format or user-oriented output format. Once you make ps select lines that have the right command name, using grep to select lines containing only the correct user name is easy since the user name field can always be matched as anchored at the start of every line. Do not match any user name that might occur later in the line. Do not match partial user names, e.g. roo or www.
  7. Do not use the ps option that searches for a user name: You cannot combine the above ps option that searches for a command name with a ps option to also search for a user name, since the result will be processes that match a command name or that match the user name, not processes that match both. Use only the above two ps options in your solution.

  8. Make sure that when you search for a user name in the output of ps that you use a pattern that ensures that the entire user name is matched and not just a prefix or a suffix. The script must not show any lines for partial user names such as roo or oot.

  9. Do not print lines from ps that look like command names. Carelessly written scripts will incorrectly print the grep command that is being used to select the right ps output line inside the script; don’t do that. Show only the required output. (If you use the correct ps options, you won’t have this problem.)

  10. Test your script and verify that all the Examples work.

Run the Checking Program to verify your work so far.

4.3 A Signal Trap Test – signaltrap.sh

Let’s use the above script to find a process and then send it some signals.

We are going to be running a shell background process for this test. Normally, the shell won’t tell you anything about your background processes until you push the Enter key and get a shell prompt. To get immediate notification, set the notify shell option as described in last term’s Login and Shell Startup Files.

signaltrap_output

  1. First, we need to run a test process to receive the signals: Run the script signaltrap.sh which is located in the Source Directory. You’ll notice this script starts and doesn’t finish – it just sits there doing nothing, and you don’t get your bash prompt back because the script isn’t finished yet. The bash prompt won’t appear until the script process is finished, killed, or stopped.
    • The script creates a log file in the current directory named signaltrap_output. Do not delete this log file.
  2. Type ^C to try to interrupt this script process.
    • Recall that typing ^C at a keyboard sends the foreground process an INT (interrupt) signal. Most processes die when they receive an interrupt signal.
    • Notice that the signaltrap.sh process did not do the normal thing (die) upon receiving the INT signal. It “caught” the signal, printed and logged a message, and refused to die.
  3. Type ^Z at the keyboard to send a STOP signal to the signaltrap.sh process.
    • You will get your bash prompt back and see a message about the process being Stopped by the signal.
    • The shell built-in jobs command will list this as a Stopped process.
  4. Use bg to resume the script process running in the background.
    • The process will resume, but the shell will not wait for it to finish. You get your shell prompt back and can enter other commands while the background process runs.
  5. Use your process_id.sh script from above to find the process id of this background script process.
    • Be sure your script finds your process, not any other process!
    • If your process_id.sh script can’t find signaltrap.sh you may need to adjust it to find commands that are shell scripts. (This may be tricky if you aren’t using the ps option described in the Hints for the ./process_id.sh script.)
  6. At your command prompt, send the signaltrap.sh script process a TERM signal (terminate) and notice that this too didn’t make the process do the expected terminate action (clean up and die).
    • The script traps and does not die on many signals. You can read the script to see which ones are handled with trap.
    • Read the messages that the script writes into its log file.
  7. Finally, send the signaltrap.sh process a KILL signal.
    • KILL signals can’t be ignored, so it should be gone – verify this.
    • The shell built-in jobs command will show that the process is gone.
    • Do you know why the script didn’t write a log message when it received the KILL signal?
  8. Find a PID of any process owned by root or by another user, and try sending it a KILL signal (or any other signal).
    • You will see an Operation not permitted error message.
    • Regular users cannot kill (send signals to) other users’ processes.
    • Re-run the command and append the error message to the signaltrap.sh log file, below all the other log messages. Do not accidentally erase the messages in the log file!
    • Verify that the log file contains several log messages and ends with the above error message as the last line.
  9. When your script is working, Document Your Script as you did in the previous assignment.

Run the Checking Program to verify your work so far.

4.4 The Temperature Script – temperature.sh

Using the specifications below, write an executable script named temperature.sh that extracts the current Ottawa Temperature from the appropriate Environment Canada XML RSS page. Use the Hints below to help you.

  1. The temperature.sh script must start with the correct Script Header lines.

  2. The script will accept no arguments.

  3. The script will print one line containing the current Ottawa Temperature, e.g. Temperature: 6.4°C

  4. The script must print a Good Error Message and Usage message if it receives any command line arguments, and exit with an exit status of 2.

otemp

  1. Create a hard link to the temperature.sh script in your own bin/ directory and name the link otemp

  2. Verify that you can now type simply otemp at a shell prompt to have the one line of current temperature display.
  3. When your script is working, Document Your Script as you did in the previous assignment.

4.4.1 Examples for temperature.sh

Your output will differ.

$ ./temperature.sh
   Temperature: 6.4°C
$ otemp
   Temperature: 6.4°C
$ ./temperature.sh one two three
./temperature.sh: Not expecting any arguments, found 3 (one two three)
Usage:  ./temperature.sh
$ otemp one two
/home/abcd0001/bin/otemp: Not expecting any arguments, found 2 (one two)
Usage:  /home/abcd0001/bin/otemp

4.4.2 Hints for temperature.sh

Start by building up the working command pipeline on your interactive command line. Get it working on the command line before you copy the working pipeline into your shell script.

  1. Refer to last term’s work with pipes and web pages shown in CST8207 Examples of Pipes and scroll down to the Display current Ottawa weather temperature example that fetches the temperature using an elinks alias and the Environment Canada XML RSS feed.

  2. As shown in the above example, use the text browser elinks with the given options (reproduced below) to retrieve the current Ottawa temperature from the given XML RSS feed URL:
    • elinks -dump -no-numbering -no-references URL
    • The URL should be the Ottawa XML RSS feed as shown in the above example.
    • Make sure you can fetch the entire RSS feed web page before continuing with the next steps. If you see “Host not found” or “Page Not Found”, you have got the wrong URL.
    • In a script, always use the full elinks command and arguments in the pipeline, not a shell alias. Shell aliases may make the script harder to read.
  3. Pipe the working elinks output into fgrep to extract the line containing the text string Temperature: from the XML RSS page.
    • The pipeline will print one line of current temperature from the XML RSS page, e.g. Temperature: 6.4°C
    • You should see only the one line of temperature output on your screen when you have the right fgrep command line.
    • Don’t use a shorter fgrep pattern, e.g. “Temp”, since that might match other lines in the RSS output some day, e.g. “Abnormal Temperature Trend”.
  4. Put the above working two-command pipeline into a script named temperature.sh that prints out the current temperature for Ottawa.
    • The active part of the script will be one line long (a pipeline).
    • A perfect solution needs only two commands separated by one pipe.
    • Do not use any shell aliases.
  5. That one active line should be preceded by code to check the number of arguments (zero arguments), plus some lines for the Script Header.
    • As with many one-line scripts, the code needed to check the arguments greatly exceeds the code that does useful work!
  6. Do not create or use an alias in your script; use the full elinks command line with the correct URL.
    • Scripts never use aliases, since aliases are meant to save typing by humans, not by scripts, and aliases make scripts harder to read.
  7. If a URL contains shell meta-characters, such as ?, you must quote the URL to prevent GLOB expansion by the shell..
    • Hide all special characters in the URL from the shell.
  8. elinks defaults to fetching pages using the UTF8 character set, which may not display well on your screen.
    • You can change the character set using the elinks -dump-charset option followed by the name of a new character set. (Try the names ascii, latin1 or the default utf8.)
  9. If the degree special character between the temperature number and the letter C doesn’t display correctly under Windwos (e.g. 6.4°C), you may need to reconfigure PuTTY for the UTF8 character set. (Remember to save your PuTTY settings.)

  10. Test your script and verify that all the Examples work.

Run the Checking Program to verify your work so far.

4.5 Sending information using a mail command – mail_temperature.sh

System administrators often have systems send them automated EMail. You will build a script that uses EMail to send you the Ottawa temperature. (You can optionally send the temperature to your mobile phone.)

  • There are many text-mode EMail clients (“Mail User Agents”) for Linux. This assignment uses the one named mail, which is fairly standard and fairly small, which makes it ideal for use in sending EMail inside scripts. Learn about EMail on the CLS.
  • Optional: If you are interested in trying a power-user text-mode mail client for everyday interactive use, try mutt and read man mutt on the CLS.
  1. Learn about EMail on the CLS, skim over the man page for the mail command, and try sending yourself EMail from the CLS to your own EMail account using this pipeline:
    • $ echo "Testing mail" | mail -s "Test" abcd0001@algonquinlive.com
    • $ who | mail -s 'See who list' abcd0001@algonquinlive.com
    • Replace the abcd0001 with your own Algonquin Live EMail address, or use your own personal EMail address instead.
    • You can pipe any text standard output into the mail program; try replacing the command on the left of the pipe with ls or date or any command that generates standard output that you can redirect.
    • Do not send binary data this way; it won’t work. Text Only
    • You can use a similar command to send EMail to any of your other EMail accounts.
  2. Following the above syntax, EMail the one line of standard output of your above temperature.sh weather script to your Algonquin EMail address with the subject: Current Ottawa Temperature
    • If the degree special character between the temperature number and the letter C doesn’t display correctly in your EMail (e.g. 6.4°C), read the Hints above about option -dump-charset.
  3. Create a script called mail_temperature.sh that will use your temperature.sh script and the above EMail syntax to send the current Ottawa temperature to your Algonquin EMail address. (Use the working command line from above.)
    1. The active part of the script will be one line long (a pipeline). A perfect solution needs only two commands separated by one pipe. Use pipes; do not use any output or input temporary files.
    2. That one line will be preceded by code to check the number of arguments (no arguments), plus some lines for the Script Header. As with many one-line scripts, the code needed to check the arguments greatly exceeds the code that does useful work!
    3. The script will use an absolute pathname to your existing temperature.sh script to generate the one line of temperature data for the script pipeline.
    4. Do not duplicate the elinks line inside this new mail script; your new script must EMail the output created by running your temperature.sh script (that contains the elinks line).
    5. You can create this script correctly even if you have not got a working temperature.sh script. (Of course, you won’t be able to fully test it without a working temperature.sh script.)

omt

  1. Create a hard link to the mail_temperature.sh script in your own bin/ directory and name the link omt (Ottawa Mail Temperature).
    • Verify that you can now type simply omt at a shell prompt to have the temperature sent to you by EMail. (If this command isn’t found, re-read the note about PATH above in the temperature script section.)
  2. When your script is working, Document Your Script as you did in the previous assignment.

Run the Checking Program to verify your work so far.

  • Optional: You can try finding and using an SMS Gateway List to find the EMail address of your SMS enabled phone, and EMail any text message from the CLS directly to your phone. (May be subject to length restrictions and incur an arbitrary delay.)
  • If the degree special character between the temperature number and the letter C doesn’t display correctly in your EMail (e.g. 6.4°C), read the Hints above about option -dump-charset.

4.6 Scheduling repeated tasks with crontab

You may find last term’s notes Crontab and At Jobs useful here.

The crontab command is used to create tasks that are run repeatedly by the system cron daemon program. These are commonly called cron jobs. You can create personal cron jobs. There is also a system file containing system cron jobs that only the super-user can edit.

If you don’t redirect all the output of command lines used in a cron job, any output will be sent to you by EMail. You will need to use the mail program to read the EMailed output generated by your cron jobs. Learn about EMail on the CLS.

  1. Read the course notes and the skim the man page for the crontab command. You may find last term’s notes Crontab and At Jobs useful here.

  2. Run the CLS command select-editor to choose a text editor for use by the crontab command. (Isn’t it time you learned some vim?)

  3. Run crontab -e to start the selected text editor to edit your personal crontab file.
    • Your personal crontab file opens in the text editor with a list of helpful comments, but no actual commands are scheduled.
    • Use the text editor to add valid crontab commands to the bottom of the file, below the comments. The commands you add will not take effect until after you save the file and exit the text editor.
    • Experiment by creating a crontab line that runs in the near future to make sure you know how cron jobs work: e.g. create a crontab line that runs the date command every minute, save, and exit. Wait a minute for the command to execute.
    • See the note above about where the date output will be sent. Learn about EMail on the CLS.
    • Use the crontab command again to edit and experiment with other valid crontab lines that run in the near future, e.g. two minutes from now, etc.
    • Use the crontab command to remove the test commands from your personal crontab when you know enough about how to create working cron jobs.
  4. Now, create a crontab line designed to run your omt program (located in your bin/ directory) at The Crontab Time.
    • Use a relative pathname to run your omt program in your bin/ directory.
    • Testing: Create and save your crontab using times in the near future while you are testing your cron job to make sure it works.
    • When you know your job works in the near future, change the time to be exactly the time required for marking.
    • You can create this crontab file correctly even if you have not got a working omt script. (Of course you won’t receive the correct output without a working omt script.)
  5. Use the crontab command with option that lists the contents of your current live crontab file. Make sure your displayed cron job is scheduled at The Crontab Time.

omt.crontab

  1. Repeat the above command and redirect the contents of your current live crontab file into an omt.crontab text file in the Base Directory. (It should contain one valid crontab line at the bottom of all the comments.)

In your cron job, did you use a relative path to the omt script name (the name that is located in your own bin/ directory)? You need to know in which directory the cron job runs, to create the correct relative path to the program in your bin/ directory.

Run the Checking Program to verify your work so far.

4.6.1 The Crontab Time

How to calculate your personal crontab time for use in cron and at jobs.

  1. Take your 9-digit student number and remove the first three digits (probably 040), leaving six digits. Use these six digits as follows:
  2. Take the first two of those six digits as a number, modulo 12, and then add 1, giving a number between 1 and 12. This is your month number.
  3. Take the next (middle) two of those six digits as a number, modulo 24, giving a number between 0 and 23. This is your hour number.
  4. Take the last two of those six digits as a number, modulo 60, giving a number between 0 and 59. This is your minute number.
  5. Take the same last two of those six digits as a number, modulo 28, and then add 1, giving a number between 1 and 28. This is your day-of-the-month number.

For example, if your nine-digit student number were 123456789, the last six digits would be 45 67 89 and:

  1. the month would be (45%12)+1 = 10
  2. the hour would be 67%24 = 19
  3. the minute would be 89%60 = 29
  4. the day of the month would be (89%28)+1 = 6

Example result for student number 123456789: October 6 at 19h29 (7:29pm).

4.7 Scheduling a command once with at

You may find last term’s notes Crontab and At Jobs useful here.

The at command is used to create a task that runs only once at some future date and time. These are commonly called at jobs. There is no system file of at jobs, since these jobs only run once.

If you don’t redirect all the output of command lines used in an at job, any output will be sent to you by EMail. You will need to use the mail program to see the EMailed output generated by your at jobs. Learn about EMail on the CLS.

  1. Read the course notes and skim the man page for the at command and note the syntax used to schedule an at job at a time and date in the future. Experiment with some at command lines that run in the near future to make sure you know how it works. You may find last term’s notes Crontab and At Jobs useful here.
  2. Use the at command to schedule a run of your omt program (located in your bin/ directory) at The Crontab Time in the year 2016.
    • Use an absolute pathname to your omt program in your bin/ directory.
    • Testing: Experiment with times in the near future while you are testing the at command to make sure it works.
    • When you know your job works, change the time to be exactly the time required for marking.
    • You can create this at job correctly even if you have not got a working omt script. (Of course you won’t receive the correct output without a working omt script.)
  3. Learn the command that displays a list of your scheduled at job numbers and display the list to make sure your job is scheduled to run at The Crontab Time in 2016.

In your at job, did you use an absolute path to the omt script name (the name is located in your own bin/ directory)?

4.7.1 Viewing scheduled at jobs

You may forget what command is scheduled in a job. What is the command syntax to show you the content of a scheduled at job, not just the job number? (NOTE: The command that lists all your at job numbers is not the same as the command that shows you what the content of the job actually is!)

In other words, use a command to display the actual command line that you submitted when you created the at job, along with all the environment information that the system adds to your at job.

atjob.txt

  1. Using the command above, display the full content of your 2016 at job and redirect it into file atjob.txt in your base directory. The file should start with a shebang line and contain about 30 lines (approximately), most of which are variable assignment statements.

Usually we don’t care to see all the environment information at the start of the queued at job file. Assuming that the command being run by at is only one line long (as it is for our 2016 job), you can show only the one-line command line itself on your screen and not see all of the associated shell environment that is created as part of the job by piping the output into a command that shows the last lines of input.

Run the Checking Program to verify your work so far.

4.8 When you are done

That is all the tasks you need to do.

Read your CLS Linux EMail and remove any messages that may be waiting. See Reading eMail for help.

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 Blackboard following the directions below.

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

5 Checking, Marking, and Submitting your Work

Summary: Do some tasks, 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 have the best mark, upload the single file that is the output of the Checking Program to Blackboard.

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.

  1. There is a Checking Program named assignment06check in the Source Directory on the CLS. Create a Symbolic Link to this program named check under your new Base Directory on the CLS so that you can easily run the program to check your work and assign your work a mark on the CLS. Note: You can create a symbolic link to this executable program but you do not have permission to read or copy the program file.

  2. Execute the above check program on the CLS using its symbolic link. (Review the Search Path notes if you forget how to run a program by pathname from the command line.) This program will check your work, assign you a mark, and display the output on your screen. (You may want to paginate the long output so you can read all of it.)

    You may run the check program as many times as you wish, to correct mistakes and get the best mark. Some task sections require you to finish the whole section before running the checking program at the end; you may not always be able to run the checking program successfully after every single task step.

  3. 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 assignment06.txt in your Base Directory on the CLS.

    • Redirect only the standard output of the Checking Program.
    • Use that exact name. Case (upper/lower case letters) matters.
    • Be absolutely accurate, as if your marks depended on it.
    • Do not edit the output file.
    • Make sure the file actually contains the output of the Checking Program!
    • The file should contain, near the bottom, a line starting with: YOUR MARK for
    • Really! MAKE SURE THE FILE HAS YOUR MARKS IN IT!
  4. Transfer the above single file assignment06.txt (containing the output from the Checking Program) from the CLS to your local computer.
    • You may want to refer to the File Transfer page for how to transfer the file.
    • Verify that the file still contains all the output from the Checking Program.
    • Do not edit this file! No empty files, please! Edited or damaged files will not be marked. Submit the file exactly as given.
    • The file should contain, near the bottom, a line starting with: YOUR MARK for
    • Really! MAKE SURE THE FILE YOU UPLOAD HAS YOUR MARKS IN IT!
  5. Upload the assignment06.txt file from your local computer to the correct Assignment area on Blackboard (with the exact name) before the due date:
    1. On your local computer use a web browser to log in to Blackboard and go to the Blackboard page for this course.
    2. Go to the Blackboard Assignments area for the course, in the left side-bar menu, and find the current assignment.
    3. Under Assignments, click on the underlined assignment06 link for this assignment.
      1. If this is your first upload, the Upload Assignment page will open directly; skip the next sentence.
      2. If you have already uploaded previously, the Review Submission History page will be open and you must use the Start New button at the bottom of the page to get to the Upload Assignment page.
    4. On the Upload Assignment page, scroll down and beside Attach File use Browse My Computer to find and attach your assignment file from your local computer. Make sure the assignment file has the correct name on your local computer before you attach it.
    5. After you have attached the file on the Upload Assignment page, scroll down to the bottom of the page and use the Submit button to actually upload your attached assignment file to Blackboard.

    Use only Attach File on the Upload Assignment page. Do not enter any text into the Text Submission or Comments boxes on Blackboard; I do not read them. Use only the Attach File section followed by the Submit button. If you need to comment on any assignment submission, send me EMail.

    You can revise and upload the file more than once using the Start New button on the Review Submission History page to open a new Upload Assignment page. I only look at the most recent submission.

    You must upload the file with the correct name from your local computer; you cannot correct the name as you upload it to Blackboard.

  6. Verify that Blackboard has received your submission: After using the Submit button, you will see a page titled Review Submission History that will show all your uploaded submissions for this assignment. Each of your submissions is called an Attempt on this page. A drop-down list of all your attempts is available.
    1. Verify that your latest Attempt has the correct 16-character, lower-case file name under the SUBMISSION heading.
    2. The one file name must be the only thing under the SUBMISSION heading. Only the one file name is allowed.
    3. No COMMENTS heading should be visible on the page. Do not enter any comments when you upload an assignment.
    4. Save a screen capture of the Review Submission History page on your local computer, showing the single uploaded file name listed under SUBMISSION. If you want to claim that you uploaded the file and Blackboard lost it, you will need this screen capture to prove that you actually uploaded the file. (To date, Blackboard has never lost an uploaded file.)

    You will also see the Review Submission History page any time you already have an assignment attempt uploaded and you click on the underlined assignment06 link. You can use the Start New button on this page to re-upload your assignment as many times as you like.

    You cannot delete an assignment attempt, but you can always upload a new version. I only mark the latest version.

  7. 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!

READ ALL THE WORDS. OH PLEASE, PLEASE, PLEASE READ ALL THE WORDS!

Author: 
| Ian! D. Allen  -  idallen@idallen.ca  -  Ottawa, Ontario, Canada
| Home Page: http://idallen.com/   Contact Improv: http://contactimprov.ca/
| College professor (Free/Libre GNU+Linux) at: http://teaching.idallen.com/
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