% CST8177 Assignment 02 -- PATH and Simple Shell Scripts % Wenjuan Jiang, Ian! D. Allen -- -- [www.idallen.com] % Fall 2014 - September to December 2014 - Updated 2015-09-06 00:38 EDT - [Course Home Page] - [Course Outline] - [All Weeks] - [Plain Text] Due Date and Deliverables ========================= > **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. - **Due Date**: `23h59 (11:59pm) Friday September 26, 2014 (end of Week 4)` - You have almost two weeks to do this assignment, but your next assignment will be available in one week and will overlap this assignment. Start work on this now! Don't delay! - Late assignments or wrong file names may not be marked. Please be accurate and punctual. - **Available online** - Version 1 -- 19h35 Sunday September 14, 2014 - Version 2 -- 02:10 Tuesday September 16, 2014 (clarified 4.5.1) - **Prerequisites** - [CST8207 GNU/Linux Operating Systems I] - All Class Notes since the beginning of term. - All your previous [Assignments]. - An ability to **READ ALL THE WORDS** to work effectively. - **Deliverables** 1. One plain text file uploaded to Blackboard according to the steps in the [Checking Program] section below. 2. Directory structure created and left for marking on the [Course Linux Server] (**CLS**).\ **Do not delete any assignment work from the CLS until after the term is over!** **WARNING:** Some inattentive students upload Assignment #02 into the Assignment #01 upload area. Don't make that mistake! Be exact. 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. More review of basic Linux command line operations and utilities, e.g. from [CST8207 GNU/Linux Operating Systems I]. 2. Explore the `PATH` mechanism of the shell 3. Verify why putting the current directory in your `PATH` is undesirable 4. Create simple shell scripts 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. The first tasks guide you through the process of reviewing the [Search Path] mechanism of the shell. In the process, you will gain some practice working with [Shell Variables]. The remaining tasks involve creating simple shell scripts. This lab uses basic scripting techniques, to be built upon in future labs. You can use the **Checking Program** to check your work after you create each script. You will create file system structure in your HOME directory, with various directories, files, and links. 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 tasks 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 these files, directories, and links in place 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; you must have your term work available right until term end. This is partially a review lab, and some of the tasks can be completed with knowledge of the material from the prerequisite course [CST8207 GNU/Linux Operating Systems I]; however, you will probably need to refresh your memory of various topics by referring to the CST8207 course notes and the Linux man pages. Your lab instructor is there to help you, but s/he will want you to have tried consulting the notes and man pages first. The prevous term's course notes are available on the Internet here: [CST8207 GNU/Linux Operating Systems I]. All the notes files are also on the CLS. You can learn about 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]. > 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**. The Source Directory -------------------- All references to the "Source Directory" below are to the CLS directory `~idallen/cst8177/14f/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` (seven letters). Tasks ===== - Do the following tasks in order, from top to bottom. - These tasks must be done in your account on the [Course Linux Server]. - **READ ALL THE WORDS!** and do not skip steps. - Run the [Checking Program] to grade your work, then upload the file to Blackboard. - Your instructor will 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.** 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. 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: CST8177-14F `-- Assignments `-- assignment02 > **This `assignment02` directory is the [Base Directory] for most pathnames > in this assignment. Store your files and answers in this Base Directory.** 3. There is a [Checking Program] named `assignment02check` in the [Source Directory] on the CLS. Follow the instructions in the first two steps at the start of [Checking Program] to create a working symbolic link to this program. Check your work so far using the checking program symlink. Exploring the search `PATH` mechanism ------------------------------------- This task explores the shell [Search Path]. **NOTE:** In this task, you will change the `PATH` variable temporarily for the current shell session only. If at any time you want to undo these temporary changes, you can simply `exit` the shell that has the changes and then start a new shell, or re-login if you exited your login shell. (Below, we suggest you create a subshell so that you don't log out when you exit!) Since this task involves temporary changes to shell variables, you cannot resume this task in the middle if you log out or exit the shell. You must always start this task over from the beginning. Do **NOT** edit your `.bashrc` to make permanent changes that affect future login sessions, unless explicitly told to do so. 1. Start a second copy of `bash` (a **nested** shell or **subshell**). (Watch the MP4 video on [Subshells]. Some sysadmin like to put the nesting level of the shell in their prompt using the `$SHLVL` variable.) You can use the `ps` command to verify that you have two copies of `bash` running. Re-read the **NOTE**, above. 2. Display the value of the shell environment variable `PATH` on your screen and verify that the standard system directory `/bin` is in the list of directories in your shell's search `PATH`. (If the `/bin` directory is not listed in your `PATH`, something is very wrong; contact your instructor.) **Hints:** There are several ways to see the value of an environment variable (or local variable) on your screen. You could use a command that shows single lines of text on your screen. Review [Shell Variables]. 3. Use a command to discover which of your `PATH` directories contains the `ls` program. Use redirection to put the output of this command (the absolute path to the `ls` command) in file `lspath.txt` in your [Base Directory]. You will need to know this pathname later. 4. Store the current value of your `PATH` variable in a new shell variable named `oldpath` by entering a shell assignment statement `oldpath=$PATH` (no blanks). Make sure that both variables `PATH` and `oldpath` have the same values. **Hints:** Some commands that can display the value of environment variable `PATH` cannot be used to display the value of the new local non-environment variable `oldpath`. Choose correctly. Since setting the value of a shell variable doesn't save it on disk, the saved value in `oldpath` is temporary, only valid for this shell. The value will be lost if you exit this shell and start a new shell. If you exit this shell before completing this task, you will lose the value of `oldpath` and must start the task over from the beginning. 5. Put the value of the shell variable `oldpath` into a new file named `savepath.txt` in your [Base Directory]. **Hint:** Display the value of the variable and use output redirection to put it into the file. It's easy and accurate. 6. Remove all write permissions from the `savepath.txt` file, so that you don't accidentally overwrite it. 7. Set your `PATH` variable to have no value. One method is to type nothing after the equals sign -- just push **Enter** after the equals: `PATH=` \ Use `echo` to display the new (empty) value of `PATH` on your screen. (Most other commands will not be found; `echo` is built-in to the shell and doesn't need a valid search `PATH`.) 8. Try to run any non-builtin command (for example, `ls`, `who`, `date`, etc.) and notice that the attempt fails because the shell cannot find a program with that name in your current (empty) search `PATH`. Type the `ls` command name and use the correct syntax to redirect just the shell error message into a file called `path_error.txt` in your [Base Directory]. **Hints:** Recall how to redirect errors using shell [Shell I/O Redirection]. Display the contents of the file to make sure the error message is in the file: If you use the right absolute command pathname, you can run a file display command even if no commands can be found because of the empty `PATH` variable of the current shell. See the next question for an example of using an absolute pathname as a command name. 9. Run the `ls` program using its absolute pathname (the one you discovered and saved earlier). You do not need any directories in your `PATH` to run a command using a pathname containing slashes. The `PATH` is not used to look for command names containing slashes. Issue a shell built-in command (for example, `echo`, `pwd`, `shopt`) and verify that built-in commands are part of the shell process itself and also do not need to be found in `PATH` directories. 10. Redirect the output of shell built-in `shopt` into a file called `shopt.txt` in your [Base Directory]. Because this is a shell built-in command, the search `PATH` is not used. 11. Restore your `PATH` variable to its original value by restoring its value from the `oldpath` variable. **Hints:** This is the reverse shell assignment statement compared to what you did earlier to save the value: simply exchange the names. If you make a mistake, re-read the **NOTE**, above. 12. Display your `PATH` variable to verify it is restored (has the same value as in the variable `oldpath`). 13. Try a few non-builtin commands to verify they are found with the restored `PATH` in place. 14. Exit the nested sub-shell and return to your original login shell. Check your work so far using the checking program symlink. Creating your first shell script -------------------------------- 1. In the [Base Directory] create the file `firstscript.sh`, containing the following two lines: a) The first line of the file should be exactly these 12 characters: `#!/bin/sh -u` (plus one more character for the newline at the end of the line). b) The second line of the file should be a command that displays the exact text: `*** It's not a "Micro$oft" World ***` on the screen. Make sure you count the asterisks and get the capitalization, quotes, and dollar sign correct. You will test that you got this right in the next few steps. 2. Make the `firstscript.sh` file executable for only the owner (you). Group and others can read the file but not execute it. **Hint:** Review [Permissions] from last term. 3. Execute the script and edit it to fix any errors. When the output of the script is correct on your screen, redirect the output into file `firstscriptout` in the [Base Directory]. **Hints:** Execute the script by typing its name. You will note that the shell cannot find `firstscript.sh` as an executable command name with no slashes, because the command is not on your search `PATH`. You need to avoid the search `PATH` by using a relative pathname containing a slash to execute this file, just as you do when executing the `check` symlink. Review [Executing a program in the current directory].) > You have just finished creating your own very simple Linux command -- a > script that prints some text to its standard output. Linux sysadmin create > dozens of command scripts that do various system administration tasks. The > scripts eliminate typing errors and make repeating tasks much easier. 4. Create the directory `bin` in your own HOME directory as a place to keep your own personal commands. **Hint:** Make sure you create this directory in your own HOME directory. 5. We will give our new command a more command-like name, without the file extension. We will at the same time link the new name into our private `bin` directory that we just created. To do this, create a hard link from your `firstscript.sh` script to the name `firstscript` (no extension) inside your `bin` directory. You now have one file inode with two names. **Hint:** Review [Links and Inodes]. 6. Make the [Base Directory] your current directory. Now, without changing directories again, use a command to display the inode numbers and names of both script files to verify that they are hard links to the same inode. Use one command with two *relative* pathnames. When the two output lines are correct (showing the relative pathnames and the identical inode numbers), save the output into file `sameinodes.txt` in the current (base) directory. 7. Change to your HOME directory. Without changing directories again, execute your new `firstscript` command that is inside your `bin` directory using the shortest relative pathname (from your HOME). Put the relative pathname you used into file `binrel.txt` in your [Base Directory]. **Hint:** A fast way to create `binrel.txt` is to `echo` the pathname that you just used and use redirection to create the file in the base directory. 8. Start a subshell. Append the absolute pathname of your new `bin` directory to the *right end* (not the *start*) of the `PATH` variable of your current shell. Remember how you did this -- you will need to do it again later in your `.bashrc` file. **Hint:** Review [Appending to PATH]. 9. Display your `PATH` to confirm that the absolute path of your `bin` directory is on the right end (not at the start). do *not* add the directory more than once -- it should only appear once in your `PATH` variable. If you need to start over, exit this subshell and then start another one to get a fresh, good copy of `PATH`. 10. if you have done the previous steps correctly, you can now type the command name `firstscript` (no slashes, no file extension) and the shell will find your `firstscript` script in your `bin` directory and execute it (because your `bin` directory is now in the `PATH` for this shell). **Hint:** Now that your `bin` directory is in your search `PATH`, you can use the TAB key to do command name completion on the `firstscript` command name, so you don't have to type the whole name. Let the shell do your typing for you! 11. When you have your own `firstscript` command working using your modified `PATH` variable, save a copy of your modified `PATH` variable in file `binpath.txt` in your [Base Directory]. Make sure there are no duplicate directories in `PATH` before you save it. Your HOME `bin` directory must be at the end. > The change we just made to this shell's `PATH` variable will be lost when > the shell exits. We need to save this change so that it happens every time > we log in. We do this using the `.bashrc` file. 12. Create a backup copy of your `.bashrc` file, in case you need to start over. 13. Make the necessary changes to your `.bashrc` file to add the absolute path of your `bin` directory to the right end of your `PATH` variable. The syntax to do this is exactly as you did earlier with your interactive shell. Save the file. 14. Log out and log in to have your `.bashrc` execute. Check your `PATH` variable to make sure the absolute path of your `bin` directory is at the right end of your `PATH`. Verify that your `firstscript` command from your own `bin` directory still works (no slashes). The shell will do command completion on this name if you use the TAB key. > You will note that every time you start a new nested subshell, your > `.bashrc` appends another copy of your HOME `bin` to your shell's search > `PATH` variable. We will learn in later assignments how to avoid this > duplication. Check your work so far using the checking program symlink. Putting the current directory in `PATH` is a bad idea ----------------------------------------------------- 1. Make your HOME directory your current directory. 2. Create a fake `ls` command using these steps: a) *Copy* the `firstscript` script you created above to a new file named `ls` in the current (your HOME) directory. b) Edit the new file, changing the text message on the second line to read exactly this (one long line): `You are running fake ls with all your privileges - this script could remove all your files!` c) Make the new file executable if it is not already. d) Execute the `ls` script *in the current directory* and make sure it prints your text message on the screen. **Hint:** To execute the `ls` script, you need a relative command pathname that includes a slash. > You have just finished setting a trap for anyone who has the current > directory `.` near the beginning their `PATH` and runs `ls` while in your > HOME directory. 3. Still in your HOME directory, type the ordinary `ls` command name and note that you get the real `ls` command, because your `PATH` does not include the current directory. You do not have `.` at the start of your `PATH` so you didn't run the fake `ls` in the current (HOME) directory. 4. Start a subshell (a second copy of the shell). 5. Make yourself a victim: temporarily put the current directory `.` at the front (start) of your current shell's `PATH` variable. **Hint:** Review [Appending to PATH], but make sure you add to the front (left) end of the `PATH` this time. 6. Display the new value of your `PATH` variable and verify that the current directory name `.` is the first directory in the list, followed by a colon character (`:`) and the rest of the search `PATH`. Redirect and save this new `PATH` into file `badpath.txt` in the [Base Directory]. 7. Still in your HOME directory (where the fake `ls` command resides), type the `ls` command name as you normally would. Notice that your `PATH` setting means you've just run the fake `ls` command, not the real `ls` command! This fake `ls` script executes with your permissions, and it has privileges to do anything to your account that your own userid can do. > Imagine you are running as the super-user `root` account (not a good idea) > and you have made the mistake of putting the current directory in your > `PATH` as we have done here. (**DON'T DO THIS!**) Imagine further that you > notice a new directory on the system that shouldn't be there. As `root` you > change into this directory and type `ls` to see what it contains. A user > has placed a fake `ls` command in this directory. Because you're `root`, > that fake `ls` command in the current directory runs with `root` privileges > -- and it can destroy your system. > > **NEVER PUT THE CURRENT DIRECTORY IN YOUR PATH!** 8. Exit the subshell that has the bad `PATH`. Make sure your current shell's `PATH` does *not* contain the current directory before you continue! Log out and back in, if needed. Check your work so far using the checking program symlink. Creating a script ----------------- This task explores [Processes and Jobs]. In this task you will create a script that prints out the number of processes each user is currently running on the system. You will create a series of scripts, each being an enhancement of the previous one, until you have the final product. NOTE: The command that gives you a "snapshot of the current processes" has several kinds of options, some with dashes (UNIX style) and some without (BSD style), because it is really two or three commands merged into one program. You sometimes find that mixing options from the different types (with and without dashes) gives error messages. It's best not to mix option types. See the first few paragraphs of the man page. 1. Run a command that prints out a "full-format listing" and "select all processes" running on the system. Search in the man page for the terms "Select all processes" and "full-format" to discover the correct two UNIX-style options. (UNIX-style means the option letters must be preceded by a dash, unlike BSD-style options.) When you run the command with these two UNIX-style options, the output will be several hundred lines long, with every line starting with the userid that owns that process. The first few lines will look similar to this: UID PID PPID C STIME TTY TIME CMD root 1 0 0 Sep12 ? 00:00:11 /sbin/init root 2 0 0 Sep12 ? 00:00:01 [kthreadd] (**Hint:** Pipe the huge output into a command that displays only the first few lines, so you can confirm the above format.) 2. Create a new two-line script file `procs.sh` in your [Base Directory] by copying your existing two-line `firstscript.sh` file and replacing the second line of the new file to use the process listing command you used from the previous step. Do *NOT* change the first line. 3. Run the new script `procs.sh` to make sure it works. It should generate the full-format, all-processes listing for you, just as if you had typed it yourself on the command line. > As described in the section on `awk` in [Data Mining], the command > `awk '{print $1}'` reads lines from standard input and prints just > the first space-delimited field of each line from that input. The output of > the process listing command from your new script is conveniently in > space-delimited columns. 4. Run a command pipeline that pipes the output from your `procs.sh` script into an `awk` command line that selects just the first leading (userid) column of each line. You should end up with a list of several hundred userids on your screen. The first three lines will be the same as the first column of the sample output given above. 5. Copy `procs.sh` to `procs_users.sh` in the same directory. 6. Change the second line in the new `procs_users.sh` file to be a command pipeline prints just the first column of the process listing. (Add the previously-used `awk` command to the end of the line to make it a command pipeline, as you did in a previous step.) Do not change the first line. 7. Run the new script `procs_users.sh` to make sure it works. It should generate a list of several hundred userids, just as if you had typed the two commands yourself on the command line. 8. Pipe the output of your new `procs_users.sh` script into the `sort` command. The output will be the same list of several hundred userids, now in sorted order. 9. Copy `procs_users.sh` to `procs_sorted.sh` in the same directory. 10. Enhance the command pipeline in the new `procs_sorted.sh` file, adding a further pipeline into the `sort` command so that the one column of userids comes out sorted. 11. Run the new script `procs_sorted.sh` to make sure it works. It should generate a list of several hundred userids in sorted order, just as if you had typed the three commands yourself on the command line. 12. Pipe the output of your new `procs_sorted.sh` script into the command that counts adjacent identical lines. Instead of hundreds of lines of output, the output will be counts of the number of processes being run by each unique userid. You will see a few dozen lines, depending on how many users are logged in. The lines will all have this output format of number followed by userid, though the actual numbers and accounts may differ: 1 102 1 UID 2 avahi 1 colord 2 cst8207a 8 cst8207c ...etc... **Hint:** There is a command that can count the number of occurrences of adjacent input lines, displaying each **unique** line preceded by the *count* of the number of times that line appeared. To recall this **unique** command name and its option to count adjacent lines, review the [Command List] from last term and the many counting **Examples of pipes** in the pages [Shell I/O Redirection] and [Data Mining]. 13. Copy `procs_sorted.sh` to `procs_counted.sh`. 14. Enhance the command pipeline in the new `procs_counted.sh` script file to show the counts of processes run by each unique userid. 15. Run the new script `procs_counted.sh` to make sure it works. It should generate a list of more than a dozen unique userids, each preceded by a count, just as if you had typed the four commands yourself on the command line. > We can now see that there are two odd things in the output that are not > account userids: > > - `102` -- a number, not a userid. This appears to be a bug in the > process listing program, since the `passwd` file does have an account > entry for uid 102: `messagebus` > - `UID` -- the column heading from the first line of output of the > process listing. We don't want to see this in our output. 16. Copy `procs_counted.sh` to `procs_counted2.sh`. 17. Enhance the command pipeline in the new `procs_counted2.sh` file to eliminate the bogus `UID` column heading in the output. There are at least two ways to do this; pick either way and make the change: - One way is to insert a pipeline filter that removes any line containing the string `UID`. **Hint:** the command that searches inside files for lines matching a pattern has an option to invert the match and only show non-matching lines. Search the `man` page. - Another way is to see if the process listing command has an option to *print no header line*. **Hint:** It does! Searching the `man` page for `no header` will find it. You will need to read about the *problematic* use of the single-letter option and how they solved it using long options. - **DO NOT** use any removal method that relies on the number of lines output or the order of the lines output, since the number of lines and the user names in those lines will change from day to day. 18. Run the new script `procs_counted2.sh` to make sure it works. It should generate a list of more than a dozen userids in sorted order, with no bogus `UID` in the output. - Re-read the note above about how **NOT** to remove the `UID` line! 19. Copy `procs_counted2.sh` to `procs_counted_header.sh`. 20. Enhance the new `procs_counted_header.sh` script so that it prints out its own header (title) line before it generates the output. The header line should be the exact text "`NumProc Account`" (15 characters, including the single space, with upper-case for the `N`, `P`, and `A`) and you can optionally output some dashed underlining under it as well, to make the heading stand out. Line up the blank in the title with the blank in the two columns of output. The output will look similar to this, though the actual numbers and accounts may differ: NumProc Account ------- ------- 1 102 2 avahi 1 colord 2 cst8207a 10 cst8207c ... etc ... 21. Run the new script `procs_counted_header.sh` to make sure it works. It should generate its own header line, some optional underlining, followed by a list of more than a dozen userids in sorted order, with no bogus `UID` in the output. - Re-read the note above about how **NOT** to remove the `UID` line! 22. The long script name `procs_counted_header.sh` is helpful for knowing what the script does, but it's much too long for a command name. Make a hard link from `procs_counted_header.sh` to the name `pch` in your HOME `bin` directory. 23. Because your `bin` directory is in your `PATH`, you should now be able to run `pch` as a command name with no slashes. You have written your second Linux command script. Check your work so far using the checking program symlink. When you are done ----------------- That is all the tasks you need to do. Check your work a final time using the [Checking Program] and save the output as described below. Submit your mark following the directions below. 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 marks file 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 `assignment02check` 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 checking this assignment, and you like what you see on your screen, **redirect** the output of the [Checking Program] into the text file `assignment02.txt` under your [Base Directory] on the CLS. 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. Submit it exactly as given. - 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 `assignment02.txt` file from the CLS to your local computer and 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. You may want to refer to your [File Transfer] notes. - Do not edit the output file. Submit it exactly as given. - 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!** 5. Upload the `assignment02.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 **assignment02** link for this assignment. a) If this is your first upload, the *Upload Assignment* page will open directly; skip the next sentence. b) 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. a) Verify that your latest *Attempt* has the correct 16-character, lower-case file name under the *SUBMISSION* heading. b) The one file name must be the *only* thing under the *SUBMISSION* heading. Only the one file name is allowed. c) No *COMMENTS* heading should be visible on the page. Do not enter any comments when you upload an assignment. d) **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 **assignment02** 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!** - I do not accept any assignment submissions by email. Use only the Blackboard *Attach File*. No word processor documents. Plain Text only. - Use the *exact* file name given above. Upload only one single file of Linux-format plain text, not HTML, not RTF, not MSWord. No fonts, no word-processing. Linux plain text only. - **NO EMAIL, WORD PROCESSOR, PDF, RTF, or HTML DOCUMENTS ACCEPTED.** - 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 these words. Don't make that mistake! Be exact. **READ ALL THE WORDS. OH PLEASE, PLEASE, PLEASE READ ALL THE WORDS!** -- | Wenjuan Jiang, Todd Kelley, and | 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/ | Defend digital freedom: http://eff.org/ and have fun: http://fools.ca/ [Plain Text] - plain text version of this page in [Pandoc Markdown] format [www.idallen.com]: http://www.idallen.com/ [Course Home Page]: .. [Course Outline]: course_outline.pdf [All Weeks]: indexcgi.cgi [Plain Text]: assignment02.txt [hyperlink URLs]: indexcgi.cgi#XImportant_Notes__alphabetical_order_ [CST8207 GNU/Linux Operating Systems I]: ../../../cst8207/14w [Assignments]: indexcgi.cgi#XAssignments [Checking Program]: #checking-marking-and-submitting-your-work [Course Linux Server]: ../../../cst8207/14f/notes/070_course_linux_server.html [Search Path]: ../../../cst8207/14w/notes/400_search_path.html [Shell Variables]: ../../../cst8207/14w/notes/320_shell_variables.html [Remote Login]: ../../../cst8207/14f/notes/110_remote_login.html [Base Directory]: #set-up-the-base-directory-on-the-cls [Source Directory]: #the-source-directory [Subshells]: ../../../cst8207/14f/notes/145_subshells.mp4 [Shell I/O Redirection]: ../../../cst8207/14w/notes/200_redirection.html [Permissions]: ../../../cst8207/14w/notes/500_permissions.html [Executing a program in the current directory]: ../../../cst8207/14w/notes/400_search_path.html#command-names-with-slashes-avoid-path [Links and Inodes]: ../../../cst8207/14w/notes/455_links_and_inodes.html [Appending to PATH]: ../../../cst8207/14w/notes/400_search_path.html#appending-to-path [Processes and Jobs]: ../../../cst8207/14w/notes/600_processes_and_jobs.html [Data Mining]: ../../../cst8207/14w/notes/805_data_mining.html [Command List]: ../../../cst8207/14w/notes/900_unix_command_list.html [Symbolic Link]: ../../../cst8207/14w/notes/460_symbolic_links.html [File Transfer]: ../../../cst8207/14f/notes/015_file_transfer.html [email]: mailto:idallen@idallen.ca [Pandoc Markdown]: http://johnmacfarlane.net/pandoc/