Updated: 2015-10-04 11:02 EDT
PS1
Shell Promptfind
to list all the pathnamestopdir
base1
, base2
, base3
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.
10h00 (10am) Monday October 5, 2015 (start of Week 5)
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.
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/cst8207/15f/assignment03/
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.
These worksheets prepare you to do the rest of the tasks listed below by executing commands via Remote Login to the Course Linux Server.
Failure to complete the worksheets will make the rest of this assignment very difficult. Do the worksheets first!
You can download Libre Office (or Open Office) for Windows to edit the Worksheet *.odt
files and save your answers. (Or you can print the PDF and write your answers on paper.) Do not use MSWord; it will mangle the format of the worksheet.
Record and save all your worksheet answers for study and quizzes!
Do a Remote Login to the Course Linux Server (CLS). All work in this assignment must be done on the CLS.
Failure to complete the worksheets will make the rest of this assignment very difficult. Do the worksheets first!
PS1
Shell PromptIndexPS1
variable syntax shown in Section 2 of Worksheet #02 HTML, set your prompt to include your user name, your computer name, and the basename of your current working directory. (See the definition of basename in the Pathnames class notes.)
[abcd0001@idallen-ubuntu ~]$
Set your PS1
prompt every time you log in to the CLS, so that the prompt changes to tell you you the basename of your current working directory. This is faster than typing pwd
all the time! You will learn later how to create a .bashrc
file to make this happen automatically every time you log in to the CLS.
Bonus Feature: If you use
\w
instead of\W
in thePS1
prompt string, the shell will display the full absolute path of your current working directory instead of just the basename. You may or may not like this feature; it doesn’t leave much room on the command line to type commands without having the command line wrap around to the next line. You choose.
As mentioned in List of Commands You Should Know, you must keep a list of command names used each week and write down what each command does. Without that list to remind you of what command names to use, you will find assignments very difficult.
CST8207-15F
directory in your CLS HOME directory.Assignments
directory in the CST8207-15F
directory.assignment03
directory in the Assignments
directory.Hint: You can create the entire directory tree above using one single command with one option and one pathname argument, as you did at the end of Section 4 in Worksheet #02 HTML. System administrators like to work efficiently – they learn how to do things quickly.
Check the structure of this directory tree by making your HOME directory your current directory and using one of these tree
commands below. Try both command lines below and use the command that gives the best-looking output in your terminal.
$ tree CST8207-15F
$ tree -A CST8207-15F
The correct output will look similar to the ASCII tree diagram below. The spelling and capitalization must be exactly as shown.
CST8207-15F
`-- Assignments
`-- assignment03
This assignment03
directory is called the Base Directory for most pathnames in this assignment. Store your files and answers in this Base Directory, not in your HOME directory or anywhere else.
Run the Checking Program to verify your work so far.
Make the Assignments
directory that you created above your current directory.
Run the command that shows the current date and time. One line should display on your screen that looks similar to this:
Fri Sep 18 16:38:37 EDT 2015
date.txt
Redo the previous command, and this time redirect the output of the command into the file date.txt
in the current directory (just as you did in Assignment #02).
Hint: Recall that you can redirect into a file any output that appears on your screen. You did this using the date
command to create the file date.txt
in Assignment #02.
Move the date.txt
file from the current directory (Assignments
) into your Base Directory using the shortest relative pathname to do so. (You did work similar to this in Section 4 of Worksheet #03 ODT.)
Use a command that shows file names to confirm that there are no files left in the current directory. (You will only see the directory basename of the Base Directory in the current directory.)
Run the Checking Program to verify your work so far.
find
to list all the pathnamesIndexMake the CST8207-15F
directory that you created above your current directory.
Hint: What is the shortest relative pathname that will take you from the Assignments
directory up to the CST8207-15F
directory?
In the CST8207-15F
directory, use a command to recursively walk the current directory and print all the pathnames under the current directory on your screen.
Hint: You used this exact command to print all the pathnames under the current directory in Section 8 of Worksheet #02 HTML.
found.txt
Repeat the same recursive command you just used and redirect the output of the command into file found.txt
in your Base Directory (not in your current directory).
Hint: For the redirection output file pathname, you must use a relative pathname that leads from your current directory down into the Base Directory. The relative pathname will contain two embedded slashes separating three name components. The basename of the relative pathname must be the destination file name found.txt
Use a command that shows file names to confirm that the found.txt
file is located in the Base Directory and not in the current directory.
Run the Checking Program to verify your work so far.
You may find it easier to type if you make the Base Directory you created above (
assignment03
) your current directory for this section. The file names in this section have been deliberately chosen to contain characters that look similar but are not the same. Pay strict attention to the names used.
calnew,txt
cal.txt
file you created in Assignment #02 HTML into the Base Directory using the new name calnew,txt
for the file. (Note carefully the punctuation character used in this name.) The Base Directory now has three files in it (and nothing else).l1dir
l1dir
directory in the Base Directory. Pay careful attention to the name; the first two characters of the name are not the same.l1dir
create two new directories named one
and two
(three letters each).one
create new directory One0ne
(six characters, including one digit zero).two
create new directory twotwO
(six letters, including one that is upper-case).Hint: You can create the entire directory tree above using one single command with one option and two pathname arguments, as you did at the end of Section 4 in Worksheet #02 HTML. System administrators like to work efficiently – they learn how to do things quickly.
Check the structure of this directory tree using the same command as you used in the previous section. The correct directory tree under the Base Directory must look similar to the ASCII tree diagram below. The spelling and capitalization must be exactly as shown.
l1dir
|-- one
| `-- One0ne
`-- two
`-- twotwO
Ildir
Copy the directory l1dir
to new directory Ildir
using the correct directory copy option, as you did in Section 3 of Worksheet #03 HTML. Pay careful attention to the new directory name; the first two characters of the name are not the same.
Hint: Ildir
must not exist before you do this! If it already exists, recursively remove it before you do the copy, or else you will get a spurious extra level of directory.
Check that the tree structure of Ildir
is exactly the same as the tree structure of the l1dir
directory from which you copied it.
Run the Checking Program to verify your work so far.
Make the Base Directory your current directory and then use a command to recursively generate a list of all pathnames using your l1dir
directory as the starting directory. (You used this recursive command above, and many times in the Section 8 in the end of Worksheet #02 HTML. Do not use the tree
or ls
commands. Use the l1dir
directory as your starting directory.)
The recursive output of all pathnames under your l1dir
directory will be exactly five lines long and will contain this exact line in the output somewhere (along with another four lines):
l1dir/one/One0ne
Make sure the exact line above appears as one of the five lines!
paths.txt
When the five lines of recursive output above on your screen looks correct, redirect the output of the command into the file named paths.txt
in the One0ne
directory that you created earlier under the Ildir
directory.
Hint: Draw a file system tree diagram so that you know what relative pathname to use. Don’t try to invent the pathname in your head!
Hint: For the output redirection file, use a relative path from your current directory down into the One0ne
directory under Ildir
. The relative pathname will contain three embedded slashes separating four name components. The basename of the relative pathname is the destination file name paths.txt
Make the One0ne
directory under Ildir
your current directory. (Make sure you get the right one under Ildir
and not l1dir
! Display your current working directory and make sure.)
Hint: Draw a file system tree diagram so that you know what relative pathname to use. Don’t try to invent the pathname in your head!
Use a command to list the files in the current (One0ne
) directory to confirm that the paths.txt
file is here. Use another command to display the contents of the paths.txt
file, and make sure it contains exactly five lines of pathnames from under the l1dir
directory.
paths.txt.copy
From in the One0ne
directory, copy the paths.txt
file (from the current directory) into the twotwO
directory that is also under the Ildir
directory, giving it the new name paths.txt.copy
as the destination file name for the copy. Use relative pathnames to do the copy.
Hint: Draw a file system hierarchy picture to help you derive the correct relative pathname. For the destination file, use a relative path from your current directory that goes up the tree and then down into the two
directory. The relative pathname will contain four embedded slashes separating five name components. The basename of the relative pathname should be the destination file name.
copycommand.txt
echo
; type the word echo
followed by a space at the start of the command line, in front of the copy command name.copycommand.txt
in the Base Directory. No output should appear on screen.The copycommand.txt
file should contain on one line the copy command name followed by two relative pathname arguments, exactly as you typed it in the preceding question.
Hints: Because the copycommand.txt
output file must be located in the Base Directory, not in the current One0ne
directory, you need to specify a relative redirection output pathname that goes up several levels to the Base Directory. The relative pathname will contain three embedded slashes and many parent directories. The basename of the relative pathname is the destination file name copycommand.txt
You will need to use the echo
command to create another file later in this assignment. Remember how you used it here.
Run the Checking Program to verify your work so far.
topdir
IndexExecute this exact command line in your account on the CLS:
~idallen/cst8207/15f/assignment03/create_topdir.sh
There is a leading tilde character ~
directly in front of the account name idallen
, indicating to the shell that the pathname starts with the HOME directory of idallen
(seven letters).
The command will create a directory named topdir
in your Base Directory. The directory will contain some sub-directories and files.
To know what files and directories have been created by the above command line, use a command that will recursively show all the files and directories under a starting directory. (You already used this command, above.) Make sure you recursively show all the files and directories, not just the first layer.
You can re-execute the above create_topdir.sh
command line to start this task over from scratch, if you make errors in this part of the assignment, but you will have to rename or remove the existing topdir
first.
All the following commands in this task section apply to files and directories under the new topdir
directory. You will have to use commands to find some of the file names mentioned here; they may be located under sub-directories. (See Searching and Finding Files.) Some of these tasks may require more than one command to complete.
Find and read the file named README.txt
(located somewhere under some directory under topdir
). You have to find this file.
Read and then delete the file foo.txt
that is in the same directory as the README.txt
file. (Do not delete any other decoy files named foo.txt
that may be in other directories.)
Move (rename) the file bar
to be bar.bak
(This is a move, not a copy. It renames the file.)
Directly under the topdir
directory, create a new empty directory named bar
(three letters). (Make sure you create bar
under topdir
, not in your HOME or any other directory.)
Find the file named stuff
(not the directory with the same name) and move (rename) that stuff
file to be named services
under the new directory bar
that you just created. (This is a move/rename, not a copy.) Make sure you move the file, not the directory with the same name.
Run the Checking Program to verify your work so far.
base1
, base2
, base3
IndexYou may find it easier to type if you make the Base Directory your current directory for this section.
When the word count is given for a command, the numbers are the values you should get if you pipe the command output into the word count command, e.g.
date | wc
base1
base1
in your Base Directory.base1
create two new directories named bdir1
and bdir2
(four letters and one digit each).bdir1
create new directory bdir1-1
(four letters, two digits, and one dash).bdir2
create new directory bdir2-1
(four letters, two digits, and one dash).Hint: You can create the entire directory tree above using one single command with one option and two pathname arguments, as you did at the end of Section 4 in Worksheet #02 HTML. System administrators like to work efficiently – they learn how to do things quickly.
Verify that the directory tree under base1
looks similar to the ASCII tree diagram below. The spelling and capitalization must be exactly as shown:
base1
|-- bdir1
| `-- bdir1-1
`-- bdir2
`-- bdir2-1
Make the Base Directory your current directory and then use a command to recursively generate a list of all pathnames using base1
as the starting directory.
Hints: You used this recursive command many times in Section 8 of Worksheet #02 HTML. Do not use the tree
or ls
commands. The recursive output of all pathnames will be exactly five lines long and will contain this exact line in the output somewhere (along with another four lines):
base1/bdir2/bdir2-1
Make sure the exact line above appears as one of the five lines! The word count of this command output must be: 5 5 70
and if the count is wrong, re-read all the words in ths step.
base1find.txt
When the recursive output above on your screen looks correct, redirect the five lines of output of the command into the file named base1find.txt
in the Base Directory. (That file name has one digit in it.) The word count of this file must also be: 5 5 70
.
RTFM and find the single-letter option to the copy program that preserves mode, ownership, and timestamps when you copy. Make a note of this option in your own course notes; you will use it often as a system administrator.
base2
Under your Base Directory create another directory base2
that contains a copy of everything you created under base1
, with the timestamps preserved.
Hint: The fastest way to do this is with a single recursive copy command, as you did in Section 3 of Worksheet #03 HTML, but add the option to preserve timestamps. Hint: Do not create the base2
directory before you copy, or else you will get a spurious extra level of directory.
Use a command to create an empty file named mt
in each of the five directories from base2
down. You will create five empty files, one in each of five directories. Hint: You can do this with one single command name and five relative pathnames.
Make the base2
directory your current directory and then use a command to recursively generate a list of all pathnames under your current directory. The recursive output of all pathnames under your current directory will be exactly ten lines long and will contain this exact line in the output somewhere (along with another nine lines):
./bdir2/bdir2-1/mt
Make sure the exact line above appears as one of the ten lines! The word count of this command output must be: 10 10 115
and if the count is wrong, re-read all the words in this step.
base2find.txt
base2find.txt
in your Base Directory (not in the current directory). The word count of this file must also be: 10 10 115
.base3
Under your Base Directory create another directory base3
that contains a copy of everything that you created under base2
, with timestamps preserved. Hint: See the previous Hint!
Under base3
rename each of the mt
files to have the number of the immediate parent directory that contains it, e.g. rename base3/mt
to be base3/mt3
and bdir2-1/mt
to be bdir2-1/mt2-1
, etc. You don’t know enough scripting yet to do this with a script; do each file manually.
Hint: The -type f
option to find
may be useful here to generate a list of only file names and not show directory names.
Make the base3
directory your current directory and then use a command to recursively generate a list of all pathnames under your current directory. The recursive output of all pathnames under your current directory will be exactly ten lines long and will contain this exact line in the output somewhere (along with another nine lines):
./bdir2/bdir2-1/mt2-1
Make sure the exact line above appears as one of the ten lines! The word count of this command output must be: 10 10 124
and if the count is wrong, re-read all the words in this step.
base3find.txt
base3find.txt
in your Base Directory (not in the current directory). The word count of this file must also be: 10 10 124
Run the Checking Program to verify your work so far.
mymaze
Create a new directory named mymaze
in your Base Directory.
Under the Source Directory there is a directory named maze
(four letters) with many, many sub-directories and sub-sub-directories, etc. (The maze contains over 21,000 pathnames.) In this large maze, find the one file with a 12-character basename that looks similar to abcd0001-txt
but where the eight-character abcd0001
part of the name is replaced by your own account userid.
maze
directory there because you know its name.maze
directory contains many hidden sub-directories; you need a special option to see hidden files and directories.cd
or ls
to find the file in the maze; the maze is very big. Use the correct command to recursively search the maze
directory for the file name.b.
of Section 8 of Worksheet #02 HTML.XXX
in the file, it is not the right file.mazepath.txt
When the above command has found your personal abcd0001-txt
file in the maze and outputs exactly one line, put the absolute pathname of your personal file (one line) into a file named mazepath.txt
in the mymaze
directory that you created in step 1 above.
Hint: It must be the absolute pathname. You will have to draw a file system diagram and figure out what that pathname is; no command will show it to you. You can test your absolute pathname by giving it as an argument to a command that reads pathnames, e.g. to ls
, wc
, cat
, etc. and make sure you get no error message.
Hint: You can use the echo
command with output redirection to put one line of text into any file. (You used the echo
comand in a similar way to create the one-line copycommand.txt
file, earlier.) When you know the absolute pathname, give the echo
command one argument that is the absolute pathname of your personal file in the maze. Make sure the pathname echoes onto your screen. Then, add output redirection to this echo
command so that the echo
output goes into the mazepath.txt
file and not onto your screen. The mazepath.txt
file should contain one line that is the absolute pathname of the found file in the maze.
treasure.txt
Copy only your one personal file from the maze into your mymaze
directory using the new file name treasure.txt
. Read the file to make sure it’s the right one before and after you copy it into your own mymaze
directory; the file content will tell you clearly that you have found the right file. If you see XXX
in the file, it is not the right file.
Hint: Be careful not to copy the entire maze
directory! Copy only the contents of one file into mymaze
.
Run the Checking Program to verify your work so far.
That is all the tasks you need to do.
Check your work 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
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.
There is a Checking Program named assignment03check
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/cst8207/15f/assignment03/assignment03check
You will learn of ways to make this 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.
You may run the Checking Program as many times as you wish, allowing you 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.
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 assignment03.txt
on the CLS, like this:
$ ~idallen/cst8207/15f/assignment03/assignment03check >assignment03.txt
$ cat assignment03.txt
assignment03.txt
file name.YOUR MARK for
assignment03.txt
(containing the output from the Checking Program) from the CLS to your local computer.
YOUR MARK for
assignment03.txt
file from your local computer to the correct Assignment area on Blackboard (with the exact name) before the due date:
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.
You will also see the Review Submission History page any time you already have an assignment attempt uploaded and you click on the underlined assignment03 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.
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!