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Tutorial2: Unix / Linux File Management

1,056 bytes added, 19:37, 10 May 2021
INVESTIGATION 1: CREATING & MANAGING DIRECTORIES
=INVESTIGATION 1: CREATING & MANAGING DIRECTORIES=
<span style="color:red;">'''ATTENTION''': Depending on your ULI101 instruction, you may be required to complete this tutorial for marks in the course.<br>Please refer to your instructor's course notes in terms of marked assigned to the course.<br><br>The due date for successfully completing this tutorial (i.e. '''tutorial 2''') is by '''Friday by midnight''' next week (i.e. '''Week 3''').<br>If your instructor has NOT assigned marks for completing this tutorial, you can perform it for practice purposes.</span><br><br> 
In this investigation, you will learn how to '''create''', '''navigate''', '''list directory contents''' and '''remove''' directories in your Matrix account.
# We will now create the subdirectories that are contained in the '''uli101xx''' directory.<br>Issue the following Linux command to move to the '''uli101xx''' directory using a '''relative''' pathname:<br><span style="color:blue;font-weight:bold;font-family:courier;">cd uli101xx</span><br><br>
# Issue a Linux command to confirm that your current location is in the ''uli101xx'' directory.<br>You should know how to issue this command from a previous tutorial.<br><br>
# Issue the following Linux command to create the directories called '''notes''', '''tutorials''' and '''examplessamples''':<br><span style="color:blue;font-weight:bold;font-family:courier;">mkdir notes tutorials examplessamples</span><br><br># Issue a Linux command to confirm that those directories have been created<br>(you should already know how to do this).<br><br>There are better ways to create the same directory structure without using the '''cd''' command.<br><br>Issuing the '''cd''' command '''<u>prior</u>''' to issuing other commands indicates to others that you are a novice or "'''newbie'''".<br>You can actually '''lose marks''' on quizzes or examples tests if you issue multiple Linux commands to performed tasks that can be performed<br>using a single Linux command with '''pathnames'''.<br><br>
# Issue the following Linux command to return to your home directory: <span style="color:blue;font-weight:bold;font-family:courier;">cd</span><br><br>
# Issue a Linux command to confirm that you are now located in your home directory.<br><br>Although we will teach you how to '''remove''' directories and their contents in another sectioninvestigation,<br>let's remove the created directory structure' and '''recreate''' the same directory structure<br>using just <u>one</u> command using pathnames.<br><br>
# Issue the following Linux command to remove all of the directories that you have created:<br><span style="color:blue;font-weight:bold;font-family:courier;">rm -r uli101xx acp100xx xyz100xx</span><br><br>
# Issue a Linux command to confirm that the '''uli101xx''', '''acp100xx''' and '''xyz100xx''' that been removed.<br><br>
# Issue the following single Linux command to create the entire directory structure:<br><span style="color:blue;font-weight:bold;font-family:courier;">mkdir -p uli101xx/notes uli101xx/tutorials uli101xx/examples samples acp100xx xyz100xx</span><br><br>'''NOTE:''' The '''-p''' option allows "parent" directories to be automatically created first to then create their subdirectories.<br><br># Issue the following Linux command to confirm that all of the directories have been created:<br><span style="color:blue;font-weight:bold;font-family:courier;">ls -ld uli101xx/ uli101xx/notes uli101xx/tutorials uli101xx/examples samples acp100xx xyz100xx</span>
<br><br>
'''Running a Shell Script to Check your Work'''
# Make certain that your current directory is '''your home directory'''.<br><br>
# Issue the following Linux command to run a checking script:<br><span style="color:blue;font-weight:bold;font-family:courier;">bash /home/murray.saul/scriptsmyscripts/week2-check-1</span><br><br># If you encounter errors, then view the feedback to make corrections, and then re-run the checking script. If you receive a congratulation message that there are no errors, then proceed to the next sectionpart.
<br>
'''Perform the Following Steps:'''
<table align="right"><tr valign="top"><td>[[Image:directory-structure-5.png|thumb|right|250px|Output of the '''tree''' command to display directory structure.]]</td><td>[[Image:directory-structure-6.png|thumb|right|250px|Output of the '''ls -R''' command to display directory structure.]]</td></table>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">tree</span><br><br>'''NOTE:''' You should see the directory structure that you created in the previous sectioninvestigation. You can also issue the '''tree''' command using a directory pathname to display the directory structure for a specific scope.<br><br>You can also use the '''-R''' option for the '''ls''' command to display all directories and subdirectories for a specified directory path (referred to as a '''recursive directory listing''').<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">ls -lR </span><br><br>What directories do you see?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">ls -lR uli101xxx</span><br><br>Note the differences between both of these commands (i.e. using and <u>not</u> using a pathname).<br><br>You can copy and move entire directories (and their contents) to other directories.<br><br><table align="right"><tr valign="top"><td>[[Image:directory-structure-7.png|thumb|right|250px|Output of the '''tree''' command to confirm copy of '''uli101xx''' directory (and contents) to the '''xyz100xx''' directory.]]</td><td>[[Image:directory-structure-8.png|thumb|right|300px|Output of the '''tree''' command to confirm movement of '''acp100 directory''' directory (and contents) to the '''xyz100xx''' diredtory.]]</td></tr></table>
#Issue the following Linux command to display the directory structure of your home directory to confirm you moved the acp100xx directory:<br><span style="color:blue;font-weight:bold;font-family:courier;">tree </span><br><br>Let's run a checking script to see if you moved and copied the directories correctly.<br><br>
# Make certain that your current directory is '''your home directory'''.<br><br>
# Issue the following Linux command run checking script:<br><span style="color:blue;font-weight:bold;font-family:courier;">bash /home/murray.saul/scriptsmyscripts/week2-check-2</span><br><br># If you encounter errors . make corrections and re-run the checking script until you receive a congratulations message, and proceed to the next sectioninvestigation.<br><br>
===Part 3: Removing Directories ===
In this sectioninvestigation, we will learn how to '''safely remove''' directories and their contents.
# Issue the following Linux command (entering "y" when prompted): <span style="color:blue;font-weight:bold;font-family:courier;">rm -ri xyz100xx</span><br><br>'''NOTE:''' You should have removed all directories that you have created.<br><br>Let's run a checking script to confirm that you have correctly removed all of those directories.<br><br>
# Issue the '''tree''' command to confirm that all of those recently created directories have been removed.<br><br>
# Issue the following Linux command to run a checking script to confirm removal of those directories:<br><span style="color:blue;font-weight:bold;font-family:courier;">bash /home/murray.saul/scriptsmyscripts/week2-check-3</span><br><br># If you encounter errors , make corrections and re-run the checking script until you receive a congratulations message, and proceed to the next INVESTIGATION.<br><br>
=INVESTIGATION 2: MANAGING TEXT FILES=
# Issue a Linux command to check that you correctly created those directories.<br><br>
# Issue the following Linux command to edit a text file called '''mytext.txt''' in the '''linux/practice''' directory:<br><span style="color:blue;font-weight:bold;font-family:courier;">nano textedit/practice/mytext.txt</span><br><br>'''NOTE:''' When using the '''Nano''' text editor, you are placed in '''INPUT''' mode, so you can enter text immediately.<br><br>[[Image:nano-text-editor-2.png|right|400px|thumb|Enter the following text that appears in this diagram.]]
# Enter the lines shown in the other diagram of the nano text editor on the right side.<br><br>'''NOTE:''' Refer to the table below for a list of<br>common '''Nano''' navigation &amp; editing commands:<br><br><table cellpadding="5"><tr><th style="border-bottom: 1px solid black;">Key(s)</th><th style="border-bottom: 1px solid black;">Purpose</th></tr><trvalign="top"><td style="font-family:courier">'''&lt;ctrl&gt;&lt;SPACEBAR&gt;''',<br>'''&lt;esc&gt;&lt;6&gt;'''</td><td>Move forward /backward one word</td></tr><trvalign="top"><td style="font-family:courier">'''&lt;escctrl&gt;&lt;a&gt;''',<br> '''&lt;ctrl&gt;&lt;SPACEBARe&gt;'''</td><td>Move back one wordto beginning/end of line</td></tr><tr><td style="font-family:courier">'''&lt;ctrl&gt;&lt;k&gt;'''</td><td>Cut line</td></tr><tr><td style="font-family:courier">'''&lt;esc&gt;^6'''</td><td>Copy Line ('''Note</td></tr><tr><td style="font-family:courier">''' to get '''^''' character, type '''&lt;shiftctrl&gt;&lt;u&gt;6''', <u>not</utd> <ctrltd>)Paste Cut/Copied Text</td></tr><tr><td style="font-family:courier">'''&lt;ctrl&gt;&lt;ug&gt;'''</td><td>Paste Cut/Copied TextDisplay help screen (ctrl-x to exit help screen)</td></tr><tr><td style="font-family:courier">'''&lt;ctrl&gt;&lt;gx&gt;'''</td><td>Display help screen (ctrl-x to Save editing changes and exit help screen)</td></tr></table><br>
# Referring to the table above, practice navigating and editing your entered lines for practice.<br><br>
# To '''save''' your editing session, press: <span style="color:blue;font-weight:bold;font-family:courier;">&lt;ctrl&gt;x</span><br><br>
# You will be prompted to modify your file: type the letter <span style="font-family:courier;color:blue;font-weight:bold">y</span> for '''yes'''.<br><br>
# The name of the file will be displayed, Press <span style="color:blue;font-weight:bold;font-family:courier;">ENTER</span>.to save editing changes for that file name.<br><br>'''NOTE:''' This prompt for file name allows you to change the name of the file if you wish.<br>By pressing '''ENTER''', it will accept the default filename.<br><br>
# Practice Perform some more editing operations based on the file ( using the nano command in '''step #4''' ) and perform more editing operations,chart above.<br><br>(just type more random lines at the bottom of this file) and then # '''saveSave''' your editing session and '''exit''' your text editor.<br><br>
===Part 2: Creating Text Files Using The vi Text Editor===
# Make certain that you are located in your home directory.<br><br>
# Refer to the following table of '''Text File Management Commands:'''<br><br><table cellpadding="5"><tr><th style="border-bottom: 1px solid black;" width="20%">Linux Command</th><th style="border-bottom: 1px solid black;">Purpose</th></tr><tr><td style="font-family:courier">'''touch'''</td><td>Create empty file(s) / Updates Existing File's Date/Time Stamp</td></tr><tr><td style="font-family:courier">'''cat'''</td><td>Display text file's contents without editing (small files)</td></tr><tr><td style="font-family:courier">'''more , less'''</td><td>Display / Navigate within large text files without editing</td></tr><tr><td style="font-family:courier">'''cp'''</td><td>Copy text file(s)</td></tr><tr><td style="font-family:courier">'''mv'''</td><td>Move / Rename text files</td></tr><tr><td style="font-family:courier">'''rm'''</td><td>Remove text file(s)</td></tr><tr valign="top"><td style="font-family:courier">'''sort'''</td><td>Sorts (rearranges) order of file contents when displayed. Content is sorted alphabetically by default. The '''-n'''''Italic text'' option sorts numerically, '''-r''' performs a reverse sort</td></tr><tr valign="top"><td style="font-family:courier">'''head''' , '''tail'''</td><td>Displays the first / last 10 lines of a text file by default. An option using a value will display the number of lines (e.g. <span style="font-family:courier">head -5 filename</span> will display first 5 lines, <span style="font-family:courier">tail -5 filename</span> will display last 5 lines).</td></tr><tr valign="top"><td style="font-family:courier">'''grep'''</td><td>Displays file contents that match a pattern</td></tr><tr valign="top"><td style="font-family:courier">'''uniq'''</td><td>Displays identical consecutive lines only once</td></tr><tr valign="top"><td style="font-family:courier">'''diff''' file1 file2</td><td>Displays differences between 2 files</td></tr><tr><td style="font-family:courier">'''file'''</td><td>Gives info about the contents of the file (e.g. file with no extention)</td></tr><tr><td style="font-family:courier">'''find'''</td><td>To find files matching specified characteristics: <!-- <table><tr><td width="30%">'''<span style="font-family:courier">find . -name "file*"</span>'''</td><td>List pathname of any filenames beginning with "file",<br>from the current directory and any subdirectories</td></tr><tr valign="top"><td>'''<span style="font-family:courier">find . -size +50k</span>'''</td><td>List pathname of any files larger than 50 kb, from the current directory and any subdirectories</td></tr><tr valign="top"><td>'''<span style="font-family:courier">find . -mmin -5</span>''' </td><td>List files modified less than 5 minutes ago</td></tr><tr> valign="top"><td>'''<span style="font-family:courier">find -P .</span>'''</td><td>Lists file pathnames in the current directory</td></tr></table> --> </td></tr></table><br>
# Confirm that you are located in your '''home''' directory.<br><br># Issue the following Linux command to create three <u>empty </u> text files in your current directory:<br><span style="color:blue;font-weight:bold;font-family:courier;">touch a.txt b.txt c.txt</span><br><br># Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">ls -l a.txt b.txt c.txt</span><br><br>Check the size in the detailed listing to confirm that these newly-created files are empty.<br><br>[[Image:vi-screen-40.png|right|300px|thumb|Nano text editor containing numbers '''1 to 40'''<br>on separate lines.]]# Use the '''nano''' text editor to edit the empty file called '''a.txt'''. <br><br>Type the number "'''1'''" and press '''ENTER'''. On the second line, type the number "'''2'''" and press '''ENTER'''.<br>Continue entering increasing number values until you reach the number '''40''' on line 40<br>(refer to the diagram on the right).<br><br># '''Save ''' and '''exit''' your editing session.<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">cat a.txt</span><br><br>Can you see all of the contents?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">more a.txt</span><br><br>Can '''NOTE:''' The '''more''' command uses the same navigation keys as with the '''man''' command<br>(refer to week 1 notes for reference). Try using keys that you view or at least used to navigate to see all of the contents?man pages.<br><br>What is the advantage of using the more command?<br><br>
# Type the letter "<span style="color:blue;font-weight:bold;font-family:courier;">q</span>" to exit the ''more'' command.<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">less a.txt</span><br><br>Is there any difference between the '''more ''' and '''less ''' commands?<br>(again press '''q''' to quit)<br><br>
# issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">sort a.txt</span><br><br>Why does the output not look what you expected? Why?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">sort -n a.txt</span><br><br>Try the same command using both the '''-n''' and '''-r''' options to see what happens.<br><br>
# issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">head a.txt</span><br><br>What is the output from this command display?<br><br>
# issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">head -7 a.txt</span><br><br>What is the output from this command display?<br><br>
# issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">tail a.txt</span><br><br>What is the output from this command display?<br>How would you issue this command to display only the '''last line ''' contained in that file?<br><br># Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">grep 2 a.txt</span><br><br>What type of output appear? Why did these lines appear (what do they all have in common)?<br><br>[[Image:end-of-line.png|right|200px|thumb|Edit the '''a.txt''' file and add to the bottom 5 new lines each consisting of the <u>same</u> text: "'''end of line'''".]]# Edit the '''a.txt''' file and add to the bottom 5 new lines each consisting <br>of the <u>same</u> text: "'''end of line'''" (refer to diagram on right).<br><br># '''Save''' your editing session and save changes to '''exit''' your filetext editor.<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">uniq a.txt</span><br><br>What do you notice happened to those newly created lines?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">cp a.txt a.txt.bk</span><br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">cp a.txt b.txt</span><br><br>
# Issue one of the commands you learned to display the contents of the file called '''b.txt''' without editing.<br><br>What happened to this file?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">mv a.txt aa.txt</span><br><br>
# Issue a Linux command to view the directory contents.<br><br>What happened to the file called '''a.txt'''? Why?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">file b.txt</span><br><br>What sort of information did it provide?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">diff aa.txt b.txt</span><br><br>What was the Was there any output? Why do you think caused the result of this outputIf not, why?<br><br># Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">diff aa.txt c.txt</span><br><br> What reason would do you think is the purpose of this type of output occur?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">find -P . </span><br><br>What is the output of this command?<br><br>
# Issue the following Linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">rm aa.txt b.txt a.txt.bk c.txt</span><br><br>
# Issue the '''ls''' command to verify that these files have been removed.<br><br>
# After you complete the Review Questions sections '''LINUX PRACTICE QUESTIONS''' to get additional practice, then work on your<br>'''online assignment #1''', '''section 2''' "''Basic Unix Commands''" (parts '''4''' to '''6''') labelled:<br> '"''Managing Files''' " , '"''Accessing Files''' " and '"''Review Exercise'''".<br><br>
= LINUX PRACTICE QUESTIONS =
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