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Tutorial3: Advanced File Management / Quoting Special Characters

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{{Admon/caution|DO NOT USE THIS VERSION OF THE LAB. This page will no longer be updated.|'''New version here:''' https://seneca-ictoer.github.io/ULI101/A-Tutorials/tutorial3 '''Andrew's students please go here:''' http://wiki.littlesvr.ca/wiki/OPS145_Lab_3}}

=ADVANCED UNIX / LINUX FILE MANAGEMENT=

|colspan="1" style="font-size:16px;font-weight:bold;border-bottom: thin solid black;border-spacing:0px;"|Course Notes

|colspan="2" style="font-size:16px;font-weight:bold;border-bottom: thin solid black;border-spacing:0px;padding-left:15px;"|Pathname Type / Filename Expansion / Quoting ~~Reference~~

|colspan="1" style="font-size:16px;font-weight:bold;border-bottom: thin solid black;border-spacing:0px;padding-left:15px;"|YouTube Videos

|- valign="top" style="padding-left:15px;"

|colspan="1" width="22%" |'''Slides:'''<ul><li>Week 3 Lecture 1 Notes: [https://wiki.cdot.senecacollege.ca/uli101/slides/ULI101-3.1.pdf PDF] | [https://~~ict~~wiki.cdot.senecacollege.ca/~~~murray~~uli101/slides/ULI101-3.1.pptx PPTX]</li><li>Week 3 Lecture 2 Notes: [https://wiki.cdot.senecacollege.~~saul~~ca/uli101/slides/ULI101-~~Week3~~3.2.pdf PDF] | [https://~~ict~~wiki.cdot.senecacollege.ca/~~~murray.saul~~uli101/~~uli101~~slides/ULI101-~~Week3~~3.2.pptx PPTX] </li></ul>

| style="padding-left:15px;" |'''Pathname / Filename Expansion:'''

* [https://www.cyberciti.biz/faq/understanding-absolute-pathnames/ Absolute]

* [https://www.oreilly.com/library/view/web-design-in/0596009879/ch04s02s02.html Relative]

* [https://docstore.mik.ua/orelly/linux/run/ch04_08.htm#:~:text=Another%20way%20to%20save%20time,is%20sometimes%20called%20%22globbing.%22 Filename Expansion Symbols]

| style="padding-left:15px;"|'''Quoting Special Characters:'''

* [http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_03_03.html Backslash '''\''' , Single ''' ' ' ''' , Double '''" "''']

'''Linux Commands:'''

* [https://man7.org/linux/man-pages/man1/echo.1.html echo]

|colspan="1" style="padding-left:15px;" width="30%"|'''Instructional Videos:'''<ul><li>[https://www.youtube.com/watch?v=ephId3mYu9o Pathname Types]</li> <li>[https://youtu.be/5FQnehwzwSM Filename Expansion Examples]</li>

<li>[https://youtu.be/3quKLqUFGHo Relative, Absolute, and Relative-to-Home Filepaths]</li>

<li>[https://www.youtube.com/watch?v=mzgfE6-ZtUY Quoting Special Characters]</li></ul>

=INVESTIGATION 1: ABSOLUTE / RELATIVE / RELATIVE-TO-HOME PATHNAMES=

'''ATTENTION''': This online tutorial will be required to be completed by '''Friday in week 4 by midnight''' to obtain a grade of '''2%''' towards this course

[[Image:dir12.png|right|350px|thumb|]]

# Make certain that your current directory is '''your home directory'''.

# Since we will be running Linux commands depending on the directory structure that you have created, issue the following Linux command to verify you created it correctly: ~~bash /home/murray.saul/scripts~~~uli101/week3-check-1

# If you encounter errors, make corrections and then re-run the checking script until you receive a congratulations message.

# Issue a Linux command to change to the '''examples''' directory in your recently-created directory structure. cd tutorial3/practice/examples

# Issue a Linux command to confirm you are located in the ''examples'' directory.

# Remembering that we are located in the '''examples''' directory, issue the following Linux command using a '''relative''' pathname to display files in the /bin directory: ls ../../../../../bin

# Let's copy the '''ls''' file from the '''/bin''' directory to your current directory (i.e. examples): cp /bin/ls .

# Issue the following Linux command: cp /bin/ls ./ls.bk What does this command do? Let's run a checking script to make certain you performed the a few of the recently-issued commands correctly.

# Issue the following: ~~bash /home/murray.saul/scripts~~~uli101/week3-check-2 # If you encounter errors, make ~~correct~~ corrections and then re-run the checking script until you receive a congratulations message, and proceed to the next INVESTIGATION.

=INVESTIGATION 2: FILENAME EXPANSION=

:'''Perform the following steps:'''

# Issue a Linux command to move to the '''~~commands~~examples''' directory (i.e. under ''practice'' directory as shown in diagram to the right). # Issue a Linux command to confirmed that you have moved to the '''~~commands~~examples''' directory. # Issue the '''touch''' command to create the following empty text files in the ''~~commands~~examples'' directory: (note ''upper'' and ''lowercase'' letters)

<div style="font-family:courier;margin-left:50px;font-weight:bold;">abc.txt def.text hij.TxT 1a4.txt 123.TXT 456.txt 6u9.txt

ab2.html 1234.txt abcdef.txt abcde.txt </div>

<ol><li value="4">~~Before proceeding, let's run a '''checking script''' to make certain~~ To verify that you properly created ~~these regular~~ those files ~~correctly.~~, issue the following: <~~br></li><li>Issue the following: ~~bash /home/murray.saul/scripts~~~uli101/week3-check-3 If you encounter errors, then make corrections (eg. '''viewing directory contents''', '''check for correct filename syntax''', '''case sensitivity''', '''missing files''', '''files in the wrong location''', etc.) and then re-run the checking script until you receive a congratulations message, and then continue with this ~~section~~investigation. '''ATTENTION''': Learning to '''fix your mistakes ''' by issuing Linux commands may be required if you make mistakes in your ~~Assignment #1! You have now been WARNED!</~~online tutorial. <li>Issue the '''ls''' command to get a listing of files in your ~~commands~~ ''examples'' directory. The output should look identical to the diagram displayed below. You can refer to this listing to see all files so you can then predict the output from Linux commands that use filename expansion symbols. [[Image:listing-1.png|left|650px|thumb|]] </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls ???.txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls ?????.txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls ??????.txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls [0-9].txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. br>Did the command work? What does this teach you about the character class [ ] symbol? </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls [0-9][0-9][0-9].txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls [a-z][a-z][a-z].txt '''Write down the expected output on ''' on paper, then '''issue the command ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command (using character class with UPPERCASE letters)?: ls [A-Z][A-Z][A-Z].txt '''Write down the expected output ''' on paper, then '''issue the command to ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command (using character class using alpha-numeric characters): ? ls [a-zA-Z0-9][a-zA-Z0-9][a-zA-Z0-9].txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls *.txt '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer. Did ALL text files get listed? Why not? </li><li>~~Issue~~ What do you think the output will be from the following Linux command: ? ls *.[tT][xX][tT] '''Write down the expected output ''' on paper, then '''issue the command ''' to check your answer.Did ALL text files get listed this time? If so, why? </li><li>'''NOTE:''' We have just been using filename expansion symbols just with the ls command. Filename expansion symbols can be used for ANY Linux file management command (e.g. '''cat''', '''more''', '''less''', '''cp''', '''mv''', '''rm''', '''ls''', etc.). Let's get some practice issuing these other Linux file management commands. </li><li>Issue the following Linux command: file *.[tT][xX][tT] ~~Write down~~ What is the ~~expected~~ purpose of this command? Which files are contained in this output ~~on paper, then issue the command to check your answer.? <li>[[Image:dir12.png|right|350px|thumb|]]Change to the '''commands''' directory using an '''absolute''' pathname (use the diagram on right-side for reference). </li><li>Issue a Linux command to confirm that you are now in the '''commands''' directory. </li><li>Issue the following Linux command(lowercase "l" NOT the number "1"): cp /bin/l.*   . View the contents of the contents directory. What did this command do? </li><li>Issue the following Linux command: rm * View the contents of the contents directory. What did this command do? </li><li>Issue the following Linux command(lowercase "l" NOT the number "1"): cp /bin/l?   . View the contents of the contents directory. What did this command do? </li><li>Issue the following Linux command: rm l[!s] View the contents of the contents directory. What did this command do? </li><li>Use a text editor (nano or vi) to create the file called '''ab''' in the '''commands''' directory that contains the line of text below, and then save editing changes to this file: This is file ab </li><li>Use a text editor (nano or vi) to create the file called '''cd''' in the '''commands''' directory that contains the line of text below, and then save editing changes to this file: This is file cd </li><li>Use a text editor (nano or vi) to create the file called '''ef''' in the '''commands''' directory that contains the line of text below, and then save editing changes to this file: This is file ef </li><li>Issue the following Linux command: cat ?? View the contents of the contents directory. What did this command do? Why does the output look strange? '''NOTE:''' Press the keys '''ctrl-c''' to return to the shell prompt. </li><li>Issue the following Linux command: cat [!l][!s] View the contents of the contents directory. What did this command do? Does the output look better? If so, why? </li></ol> : Proceed to the next INVESTIGATION.

= INVESTIGATION 3: QUOTING SPECIAL CHARACTERS =

As discussed in the above ~~section~~investigation, there are some special characters that the shell uses to perform an operation; ~~for example,~~ including the filename expansion ~~symbols~~symbol: '''* ~~or ?~~'''

There is a method ~~to instruct~~ make the ~~Linux~~ shell to '''ignore the purpose of a special ~~character~~ characters''' and ~~just interpret~~ treat as '''regular text'''.

In this ~~section~~investigation, you will learn '''three unique methods''' to quote special characters.

:'''Perform the Following Steps:'''

[[Image:quotation.png|right|350px|thumb|Using quotation to make the shell '''ignore the purpose of special characters''' and treat as '''regular text'''.]]# ~~Make certain~~ Issue a Linux command to confirmed that you are ~~currently located~~ still in ~~your home~~ the '''commands''' directory (if not, change to the ''commands'' directory and confirm).

# Issue the following Linux command: echo hello there '''NOTE:''' the '''echo''' command is used to display text onto your terminal.

# Issue the following Linux command: echo * hello * What happened? What is shown in addition to the text "hello". Why do you think those filenames are also being displayed?

# Issue the following Linux command: echo \* hello \* What do you notice? What does the \ character do?

# Issue the following Linux command: echo "* hello *" Is there a difference between this command and the previous command?

# Issue the following Linux command: echo '* hello *' Is there any difference between this command and the two previous commands?

# Issue the following Linux command: echo $USER '''NOTE''': The environment variable '''USER''' contains the current user's login name. The '''$''' character immediately followed by the environment variable name causes it to ~~expand to the value~~ ~~that~~ expand to the ~~variable contains. The~~ '''~~echo~~value''' ~~command displays~~ that the ~~current login name of the user~~variable contains. # Issue the following Linux command (using single quotes): echo '* $USER*' What happened? Why is the output display like this? # Issue the following Linux command (using double quotes): echo "* $USER*" What happened? Why? # Let's use quoting special characters for a couple of other commands. Move to the '''lesson2''' directory. Confirm that you are currently located in the ''lesson2'' ~~directory. # Issue the following Linux command: cp /bin/ls . # Issue the '''ls''' command to verify that there are copied files in your lesson2~~ directory. '''NOTE:''' Although it is NOT RECOMMENDED to create a filename using a special character (remember ~~that~~ file naming ~~rule~~rules?), we will create an empty file called "*"

# Issue the following Linux command (using single quotes): touch '*'

# Issue the '''ls''' command. Do you now see a file called "*" in addition to the other copied files?

# Issue the following Linux command: cp /bin/ls .

# Issue the following Linux command (using single quotes): touch '*'

# Issue the '''ls''' command to view the files in your current directory.

# Issue the following Linux command (using single quotes): rm '*'

# Issue the '''ls''' command to confirm that the file called "*" has been removed in your current directory. What happened this time?

# ~~After you complete~~ Complete the Review Questions sections to get additional practice, then work on your '''online assignment 1''' and complete '''sections 3 to 6''' labelled: '''Directory Management''' , '''Practice Commands To Create A Directory Structure''' , '''Create A Directory Structure''' and '''Practice Specifying Path Names'''. When you have completed these remaining sections, and you main menu indicates you have completed 6 out of 6 sections, then you will have successfully completed your assignment #1.

= LINUX PRACTICE QUESTIONS =

The purpose of this section is to obtain extra practice to help with your ~~assignment #1,~~ quizzes, your midterm, and your final ~~ezam~~exam.

Here is a link to the MS Word Document of ALL of the questions displayed below but with extra room to answer on the document to

simulate a quiz:

https://~~ict~~wiki.cdot.senecacollege.ca/~~~murray.saul~~uli101/~~uli101~~files/uli101_week3_practice.docx

Your instructor may take-up these questions during class. It is up to the student to attend classes in order to obtain the answers to the following questions. Your instructor will NOT provide these answers in any other form (eg. e-mail, etc).

# Assuming you are still located in the “backup” directory. Write a Linux command using a relative-to-home pathname to remove all files that end with the extension “.txt” in the “final” directory.

# Write a Linux command using an absolute pathname to list all files that consist of just 4 consecutive characters that are contained in your home directory.

# Write a Linux command using a relative pathname to list all files that begin and end with a number.# Write a Linux command using a relative-to-home pathname to list all files that begin with a number but ends with any character other than a number.# Assuming you are in your home directory. Write a Linux command using a relative pathname to view the contents of regular files whose file names only consist of 5 consecutive numbers. # Write a Linux command to display the following message: *** Hello ***~~ ~~

# Write a Linux command to display the following message (including quotation marks): “This is my message”

_________________________________________________________________________________

Author: Murray Saul

License: LGPL version 3

Link: https://www.gnu.org/licenses/lgpl.html

_________________________________________________________________________________

[[Category:ULI101]]

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