View source for Tutorial2: Unix / Linux File Management

=UNIX / LINUX FILE MANAGEMENT CONCEPTS=
<br>
===Main Objectives of this Practice Tutorial===

:* Understand the purpose of Directories. 

:* List '''Common Directories''' that are Contained in a Typical '''Unix / Linux Filesystem'''

:* Use Common '''Unix / Linux Commands''' to Perform '''Directory Management''' Tasks.

:* Use '''Text Editors''' to Create and Modify Text Files

:* Use Common '''Unix / Linux Commands''' to Manipulate text filss.
<br><br>

===Tutorial Reference Material===

{|width="100%" cellspacing="0" cellpadding="10"

|- valign="top"

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

|colspan="2" style="font-size:16px;font-weight:bold;border-bottom: thin solid black;border-spacing:0px;padding-left:15px;"|Linux Command/Shortcut Reference<br>

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

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

|colspan="1" |Slides:<ul><li>[https://ict.senecacollege.ca/~murray.saul/uli101/ULI101-Week2.pdf PDF] | [https://ict.senecacollege.ca/~murray.saul/uli101/ULI101-Week2.pptx PPTX]</li></ul>Tutorials:<ul><li>[http://www.cheat-sheets.org/saved-copy/Nano_Cheat_Sheet.pdf Nano Reference Sheet (PDF)]</li><li>[https://www.smashingmagazine.com/2010/05/vi-editor-linux-terminal-cheat-sheet-pdf Vi Reference Sheet (PDF)]</li><li>[http://czegel.com/seneca/uli101/lectures/Lecture2.html Les Czegel's Week 2 Notes (HTML)]</li></ul>


|  style="padding-left:15px;" |File Management
*[http://man7.org/linux/man-pages/man1/pwd.1.html pwd]<br>
*[http://man7.org/linux/man-pages/man1/cd.1p.html cd]<br>
*[http://man7.org/linux/man-pages/man1/ls.1p.html ls]<br>
*[https://www.systutorials.com/docs/linux/man/1-tree/ tree]<br>
*[http://man7.org/linux/man-pages/man1/mkdir.1.html mkdir]<br>
*[http://man7.org/linux/man-pages/man1/rmdir.1.html rmdir]<br>
*[http://man7.org/linux/man-pages/man1/cp.1.html cp]<br>
*[http://man7.org/linux/man-pages/man1/mv.1p.html mv]<br>
*[http://man7.org/linux/man-pages/man1/rm.1.html rm] , [http://man7.org/linux/man-pages/man1/rm.1.html rm -r]<br>

|  style="padding-left:15px;"|Text Editors /<br>File Content
*[http://man7.org/linux/man-pages/man1/vi.1p.html vi] , *[https://linux.die.net/man/1/nano nano]<br>
*[http://man7.org/linux/man-pages/man1/cat.1.html cat]<br>
*[http://man7.org/linux/man-pages/man1/more.1.html more] , [http://man7.org/linux/man-pages/man1/less.1.html less]<br>
* [http://man7.org/linux/man-pages/man1/head.1.html head] , [http://man7.org/linux/man-pages/man1/tail.1.html tail]
*[http://man7.org/linux/man-pages/man1/touch.1.html touch]<br>
*[http://man7.org/linux/man-pages/man1/file.1.html file]<br>
*[http://man7.org/linux/man-pages/man1/find.1.html find]<br>
*[http://man7.org/linux/man-pages/man1/diff.1.html diff]<br>
*[http://man7.org/linux/man-pages/man1/sort.1.html sort]<br>
*[http://man7.org/linux/man-pages/man1/uniq.1.html uniq]<br>
*[http://linuxcommand.org/lc3_man_pages/grep1.html grep]<br>

|colspan="1" style="padding-left:15px;" width="30%"|Brauer Instructional Videos:<ul><li>[https://www.youtube.com/watch?v=UfAFAipked0&list=PLU1b1f-2Oe90TuYfifnWulINjMv_Wr16N&index=3 Basic File Actions<br>(touch, ls -l, cp, cp -r, mv, mkdir, mkdir -p, rm, rmdir, rm -r)]</ul>

|}

= KEY CONCEPTS=

===Unix / Linux Directories===

[[Image:directory-structure-1.png|thumb|right|350px|In Unix / Linux (as opposed to MS Windows), there are no drive letters (such as '''C:''', or '''D:''').<br><br> All files and directories appear under a single ancestor directory called "the '''root''' directory".<br><br>A path points to a file system location by '''following the directory tree hierarchy''' expressed in a string of characters in which path components, separated by a delimiting character, represent each directory. The '''delimiting character''' is most commonly the slash ("'''/'''").]]
The Unix/Linux file system is '''hierarchical''', similar to other operating systems such as<br>'''Windows''', '''Mac OSX''', etc.
Files are organized in '''directories'''. Directories may contain sub-directories.

In Unix / Linux (as opposed to MS Windows), there are no drive letters (such as C:, or D:). All files and directories appear under a single ancestor directory called the "'''root directory'''".

Learning how to issue Linux commands for navigating the Linux filesystem and manipulating directory and files are '''essential skills''' for Linux users and administrators.

In the Linux (Unix) OS, the "'''root directory'''" / is the  starting directory, and other "child directories",  "grandchild directories", etc. can be created when required. The hierarchical structure resembles an "upside-down tree". There is actually a command called '''tree'''  that can display a "'''tree diagram'''"!
<br><br>

=== Directory Pathnames ===

<i>A '''pathname''' is used to specify a the location of a file within the file system.<br>
A pathname points to a file system location by '''following the directory tree hierarchy''' expressed in a string of characters in which path components, separated by a delimiting character, represent each directory. The '''delimiting character''' is most commonly the slash ("'''/'''").</i>

Reference: https://en.wikipedia.org/wiki/Path_(computing)


The following table displays and defines commonly used directories<br>(listed by directory pathname) for for ALL Unix / Linux Filesystems:<br>

Please take a few moments to review these pathnames.
<br><br>

[[Image:directory-structure-2.png|thumb|right|500px|'''Common directory pathnames'''<br>for for ALL Unix / Linux Filesystems.]]<table cellpadding="5"><tr><th style="border-bottom: 1px solid black;">Directory Pathname</th><th style="border-bottom: 1px solid black;">Purpose</th></tr><tr><td>'''/'''</td><td>Root directory (ancestor to all directories)</td></tr><tr><td>'''/home'''</td><td>Used to store users’ home directories
</td></tr><tr><td>'''/home/username'''</td><td>A '''<u>specific</u>''' User's Home Directory</td></tr><tr><td>'''/bin'''</td><td>Common system binaries (commands) </td></tr><tr><td>'''/usr/bin'''</td><td>Common utilities (commands) for users. </td></tr><tr><td>'''/usr/sbin'''</td><td>Common utilities for system administration  </td></tr><tr><td>'''/etc'''</td><td>System administration files (eg. passwd)</td></tr><tr><td>'''/var'''</td><td>Dynamic files (log and mail files)</td></tr><tr><td>'''/tmp , /var/tmp'''</td><td>Temporary files for programs</td></tr><tr><td>'''/dev'''</td><td>Device driver files (terminals, printers, etc.)
</td></tr></table><br>


When you log into your Matrix account, you are automatically directed to your '''home''' directory. This directory is where the user can store files, and create subdirectories to organize their files.

We will now learn to create and manage subdirectories within <u>your</u> home directory.
<br><br>

=INVESTIGATION 1: MANAGING DIRECTORIES=

<br>
In this investigation, you will learn to '''create''', '''navigate''', '''list contents''' and '''remove''' directories in your Matrix account.


'''Directory File Naming Rules'''

Before you learn how to create directories, it is important to understand what represents an appropriate directory filename.

Listed below are some common '''file-naming rules''':

* Unix/Linux characters are '''case sensitive'''. It is recommended to be consistent (e.g. use all lowercase letters)
* Adopt a '''consistent directory naming scheme''' (this will  help you to navigate within your directory structure)
* Make your directory names '''meaningful'''
* '''Avoid non-alphanumeric characters''', as they may have a  special meaning to the system that will make your work more difficult when changing to directories, etc.
* '''Avoid using spaces''' for directory names (consider periods,  hyphens, and underscores instead)


===Part 1: Creating Directories ===

[[Image:directory-structure-3.png|thumb|right|350px|'''Tree Diagram''' of Directory Structure to Create in your Home Directory (displayed in blue text).]]
Creating subdirectories within your home directory makes it more '''efficient''' to save and access files on your Linux server.

A comparison would be rooms in a '''house'''. If there were no rooms, just one large room in a 3,000 square foot house, it would be "messy" and difficult to locate items. Each '''room''' in a house is used to for a specific purpose to be more productive to perform a task such as a kitchen, bedroom, bathroom, etc.


You would like to create a directory structure within your home directory as displayed in the diagram on the right aide.


As previously mentioned, the '''root''' directory is the "'''starting point'''" in the Matrix file system and '''your userid''' contained within the '''/home''' directory represents '''<u>'''YOUR'''</u> home directory''' where you can create files (both directory files, text files, etc).


'''Perform the Following Steps:'''

# '''Login''' to your matrix account.<br><br>
# Issue a command to '''confirm''' that you are located in your home directory<br>(You should know how to do this from the previous tutorial).<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">mkdir uli101</span><br><br>'''NOTE:''' You should always confirm that you have created a directory.<br>This can be done by issuing the ls command.<br><br>[[Image:directory-structure-4.png|thumb|right|350px|'''Creating''' and '''Confirming''' the Creation of a Directory.]]
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">ls uli101</span><br><br>There are no contents that are contained in this newly-created directory; therefore, no contents appear. A useful option '''-d''' can be used to confirm that the actual <u>directory</u> has been created as opposed to viewing the contents of the directory.<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">ls -d uli101</span><br><br>You should now see just the directory listed. You can also combine the '''-d''' and '''-l''' options to provide more detail regarding the newly-created directory.<br><br>
# Issue the following Linux command:<span style="color:blue;font-weight:bold;font-family:courier;">ls -d -l uli101</span><br><br>How can you confirm from the output of this command that the file uli101 is a directory?<br><br>
# Issue the following Linux command:<span style="color:blue;font-weight:bold;font-family:courier;">ls -ld uli101</span><br><br>Is the output from this command the same was the output from the previous command?<br>If so, what does this say about how to use multiple options for Linux commands?<br><br>
# Issue the following Linux command to create the '''acp100''' and '''xyz100''' directories: <span style="color:blue;font-weight:bold;font-family:courier;">mkdir acp100 xyz100</span><br><br>'''NOTE:''' You can create multiple directories by issuing the '''mkdir''' command with <u>multiple arguments</u>.<br><br>
# Issue the following Linux command to confirm that those directories have been created: <span style="color:blue;font-weight:bold;font-family:courier;">ls -ld acp100 xyz100</span><br><br>
# We will now create the subdirectories that are contained in the '''uli101''' directory.<br>Issue the following Linux command to move to the '''uli101''' directory: <span style="color:blue;font-weight:bold;font-family:courier;">cd uli101</span><br><br>
# Issue a Linux command to confirm that your current location is in the uli101 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 '''examples''': <span style="color:blue;font-weight:bold;font-family:courier;">mkdir notes tutorials examples</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>
#This technique is considered to be '''inefficient'''. There are options and ways to create the same directory structure without using the cd command and only issue a single Linux command.<br><br>Using this inefficient method tends to show that you are a novice or "'''newbie'''", and you may '''lose marks''' if you issue multiple Linux commands to performed tasks that can be performed using only a single Linux command.<br><br>Although we will teach you how to '''remove''' directories and their contents in a future section, let's change back to your '''home''' directory and issue a command to '''remove the directory structure''' that you just created so you can learn a more efficient method of creating the same directory structure.<br><br>
# Issue Linux commands to move to your home directory and confirm that your current directory is your home directory<br>(You should know how to do this).<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 uli101 acp100 xyz100</span><br><br>'''NOTE:''' You will learn how to '''safely''' remove directories and their contents in another section.<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 uli101/notes uli101/tutorials uli101/examples acp100 xyz100</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 uli101 uli101/notes uli101/tutorials uli101/examples acp100 xyz100</span><br><br>

'''Running a Shell Script to Check your Work'''

Although you are being asked to create the directory structure, you might have made some mistakes:<br>For Example:<br>

* Forgetting to create a directory.
* Making syntax errors (eg. spelling or mixing up character case)
* Not creating subdirectories within specified directories.


<table align="right"><tr valign="top"><td>[[Image:script-check-1.png|thumb|right|250px|If all all check pass, then user performed task correctly and can continue.]]</td><td>[[Image:script-check-2.png|thumb|right|450px|If there is a warning, then feedback is provided to user to correct and re-run checking script.]]</td></table>
To check for mistakes, a '''shell script''' has been created to check your work. If the checking shell script detects an '''error''', then it will provide feedback and offer constructive feedback on how to fix that problem so you can re-run the checking shell scripts until your work is correct.


'''Perform the Following Steps:'''

# 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/scripts/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 section.
<br>

===Part 2: Viewing Directory Contents / Copying & Moving Directories===

Now that you have learned how to efficiently create your directory structure, you will now learn how to issue Linux commands to '''view directory contents''' as well as '''copy''' and '''move''' directories.


'''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 section. 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 uli101</span><br><br>Note the differences between both of these commands.<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 '''uli101''' directory (and contents) to the '''xyz''' 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 '''xyz''' diredtory.]]</td></tr></table>
# Issue the following Linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">cp -R uli101 xyz100</span><br><br>
#Issue the following Linux command to display the directory structure of your home directory to confirm you copied the uli101 directory:<br><span style="color:blue;font-weight:bold;font-family:courier;">tree</span><br><br>
# Issue the following Linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">mv acp100  xyz100/uli101/tutorials</span><br><br>
#Issue the following Linux command to display the directory structure of your home directory to confirm you copied the uli101 directory:<br><span style="color:blue;font-weight:bold;font-family:courier;">tree</span><br><br>Let's download and 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/scripts/week2-check-2</span><br><br>
# If you encounter errors and re-run the checking script until you receive a congratulations message, and proceed to the next section.<br><br>

===Part 3: Removing Directories ===

In this section, we will learn how to '''safely remove''' directories and their contents.


'''Perform the Following Steps:'''

# Confirm that you are located in your home directory.<br><br>The '''rmdir''' command is used to remove <u>empty</u> directories.<br><br>
# Issue the following Linux command to remove the empty directory called '''uli101/tutorials''': <span style="color:blue;font-weight:bold;font-family:courier;">rmdir uli101/tutorials</span><br><br>
# Issue the following Linux command to remove the empty directory called '''uli101''': <span style="color:blue;font-weight:bold;font-family:courier;">rmdir uli101</span><br><br>NOTE: You should get an error message, since the '''uli101''' directory is '''NOT''' empty.<br><br>To remove non-empty directories, you can use the '''rm -r''' command.<br>The '''-r''' option stands for recursive, which can travel down the directory paths and their contents.<br><br>
# Issue the following Linux command to remove the '''uli101''' directory and its contents: <span style="color:blue;font-weight:bold;font-family:courier;">rm -r uli101</span><br><br>
# Issue the '''tree''' command to confirm that the uli101 directory (contained in your home directory) and its contents have been removed.<br><br>'''NOTE:''' To <u>safely</u> remove non-empty directories, you can add the '''-i''' option which will prompt the user if they wish to remove contents as it your travel recursively down a directory to remove directories and their contents.<br><br>
# Issue the following Linux command (entering "y" when prompted): <span style="color:blue;font-weight:bold;font-family:courier;">rm -ri xyz100</span><br><br>'''NOTE:''' You should have removed all directories that you have created.<br><br>Let's download and run a checking script to see if you have removed all of the directories that you earlier created.<br><br>
# Make certain that your current directory is '''your home directory'''.<br><br>
# Issue the following Linux command to run a checking script: <span style="color:blue;font-weight:bold;font-family:courier;">bash /home/murray.saul/scripts/week2-check-3</span><br><br>
# If you encounter errors 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=

<table align="right"><tr valign="top"><td>[[Image:nano-text-editor-1.png|thumb|right|250px|The '''Nano Text Editor''' is Easy to Operate for Novice Users.]]</td><td>[[Image:vi-text-editor-1.png|thumb|right|300px|The Vi Text Editor, although taking longer to master, has outstanding features and allow the user to be more productive.]]</td></tr></table>
<br>
Since IT students will be working in the Unix / Linux command line environment, it is useful to learn a least a couple of command-line '''text editors'''. 

Although '''programming students''' can use '''graphical IDE's''' to code and compile programs, they can '''create source code''' using a text editor in the Linux system, and '''compile their source code''' to generate executable programs (without having to transfer them for compilation or execution).

'''Networking and Tech Support students''' would find a text editor useful to '''edit configuration files'''. These students in upper grades will become familiar with the process of installing, configuring, and running network services and text editors are an important tools<br>to help setup but also "tweak" or make '''periodic changes in networking services configuration'''.

A general rule is for a student to '''expose themselves to a number of different text editors and then use one that they feel most comfortable working with'''. The two most readily-available command line text editors in Linux are '''Nano''' and '''vi'''. The Nano text editor would seem like an easier-to-use text editor, but vi (although taking longer to learn) has outstanding features and allow the user to be more productive.
<br><br>

===Part 1: Creating Text Files Using The Nano Text Editor===

<table align="right"><tr><td>[[Image:directory-structure-10.png|right|250px|thumb|]]</td><td>[[Image:nano-text-editor-2.png|right|450px|thumb|Enter the following text that appears in this diagram.]]</td></tr></table>

You will now learn basic editing skills using the Nano text editor including '''creating''', '''editing''', and '''saving''' text files.

'''Perform the Following Steps:'''

# Create the following directory structure (displayed on the right side) by issuing a single Linux command <br>(You should know how to perform this task).<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 uli101/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>
# Enter the lines shown in the other diagram of the nano text editor on the right side.<br><br>'''NOTE:''' The '''^''' symbol represents press the '''&lt;ctrl&gt;''' followed by a character.<br><br>
# To '''save''' your editing session, press: <span style="color:blue;font-weight:bold;font-family:courier;">&lt;ctrl&gt;&lt;x&gt;</span><br><br>
# You will be prompted to modify your file: type the letter '''y''' 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>.<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>
# Refer to the table below for a list of the most common Nano editing commands and try them out:<br><br><table cellpadding="5"><tr><th style="border-bottom: 1px solid black;">Keyboard Combination</th><th style="border-bottom: 1px solid black;">Purpose</th></tr><tr><td>'''&lt;ctrl&gt;&lt;SPACEBAR&gt;'''</td><td>Move forward one word</td><tr><td>'''&lt;esc&gt;&lt;SPACEBAR&gt;'''</td><td>Move back one word</td></tr></tr><tr><td>'''&lt;ctrl&gt;&lt;k&gt;'''</td><td>Cut line</td></tr><tr><td>'''&lt;alt&gt;&lt;M&gt;&lt;^&gt;'''</td><td>Copy Line</td></tr><tr><td>'''&lt;ctrl&gt;&lt;u&gt;'''</td><td>Paste Cut/Copied Text
</td></tr><tr><td>'''&lt;ctrl&gt;&lt;g&gt;'''</td><td>Display help screen (ctrl-x to exit help screen)</td></tr></table><br>

===Part 2: Creating Text Files Using The vi Text Editor===

[[Image:vi-text-editor-2.png|right|350px|thumb|The online vi-tutorial provides users "hands-on" experience of using the vi text editor.]]
An '''online tutorial''' has been created to give you "hands-on" experience on how to use vi text editor. It is <u>recommended</u> that you run this online tutorial in your Matrix account to learn how to create and edit text files with the vi text editor.


'''Perform the Following Steps:'''

# Issue the following to run the vi online tutorial:<br><span style="color:blue;font-weight:bold;font-family:courier;">/home/murray.saul/vi-tutorial<br><br>
# In the tutorial menu, select the first menu item labelled "'''USING THE VI TEXT EDITOR'''"<br><br>
#Read and follow the instructions in the tutorial. Eventually, it will display a '''simulated''' vi environment and will receive step-by-step instructions on how to use this text editor.<br><br>
# When you have completed that section, you will be returned to the main menu. If you want to get extra practice, you can select the menu item labelled "'''REVIEW EXERCISE'''".<br><br>
# When you want to exit the tutorial, select the menu option to exit the tutorial.<br><br>

===Part 3: Manage / Manipulate Text File Content===

We conclude this tutorial by learning to use commands that manage the content contained instead text files whether it relate to '''viewing''' or '''manipulating''' file content.<br><br>

'''Perform the Following Steps:'''

# View the following table of Text File Management commands Your instructor should have demonstrated in class how to use these commands):<br><br><table cellpadding="5"><tr><th style="border-bottom: 1px solid black;">Linux Command</th><th style="border-bottom: 1px solid black;">Purpose</th></tr><tr><td>'''touch'''</td><td>Create empty file(s) / Updates Existing File's Date/Time Stamp</td></tr><tr><td>'''cat'''</td><td>Display text file's contents without editing (small files)</td></tr><tr><td>'''more , less'''</td><td>Display / Navigate within large text files without editing</td></tr><tr><td>'''cp'''</td><td>Copy text file(s)</td></tr><tr><td>'''mv'''</td><td>Move / Rename text files</td></tr><tr><td>'''rm'''</td><td>Remove text file(s)</td></tr><tr valign="top"><td>'''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>'''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. head -5 filename will display first 5 lines, tail -5 filename will display last 5 lines).</td></tr><tr valign="top"><td>'''grep'''</td><td>Displays file contents that match a pattern</td></tr><tr valign="top"><td>'''uniq'''</td><td>Displays identical consecutive lines only once</td></tr><tr valign="top"><td>'''diff''' file1 file2</td><td>Displays differences between 2 files</td></tr><tr><td>'''file'''</td><td>Gives info about the contents of the file (e.g. file with no extention)</td></tr><tr valign="top"><td>'''find'''</td><td>To find files matching specified characteristics:<table><tr valign="top"><td width="20%">'''find . -name "file*"'''</td><td>List pathname of any filenames beginning with "file",<br>from the current directory and any subdirectories</td></tr><tr valign="top"><td>'''find . -size +50k'''</td><td>List pathname of any files larger than 50 kb, from the current directory and any subdirectories</td></tr><tr valign="top"><td>'''find . -mmin -5''' </td><td>List files modified less than 5 minutes ago</td></tr><tr> valign="top"><td>'''find -P .'''</td><td>Lists file pathnames in the current directory</td></tr></table></td></tr></table><br><br>
# Confirm that you are located in your '''home''' directory.<br><br>
# Use the '''touch''' command to create the empty files called '''a.txt''', '''b.txt''', and '''c.txt'''<br><br>
# 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'''. Continue entering increasing number values until you reach the number '''40''' on line 40.<br><br>
# Save 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 you view or at least navigate to see all of the contents?<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>
# Edit the '''a.txt''' file and add to the bottom 5 new lines each consisting of the <u>same</u> text: "'''end of line'''" and save changes to your file.<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 output? Why do you think caused the result of this output?<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 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: <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 to get additional practice, then work on your '''online assignment #1''',<br>'''section 2''' labelled "Basic Unix Commands" (parts '''4''' to '''6''') in this section which are respectively labelled: '''Managing Files''' , '''Accessing Files''' and '''Review Exercise'''.<br><br>

= LINUX PRACTICE QUESTIONS =

The purpose of this section is to obtain '''extra practice''' to help with '''quizzes''', your '''midterm''', and your '''final 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.senecacollege.ca/~murray.saul/uli101/uli101_week2_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).


'''Review Questions:'''
[[Image:directory-structure-11.png|right|350px|thumb|]]
# Write a single Linux command to create the directory structure starting from your home directory from the diagram displayed on the right. 
# Write a Linux command to display a detailed listing of '''history''' directory.<br>How would this command differ if you wanted to also view hidden files as well?<br>
# Write a Linux command to change to the '''project''' directory.<br>What command would you issue to return to your home directory?<br>
# Write a Linux command to copy the '''project''' directory and its contents to the '''history''' directory.
# Write a Linux command to move the directory called '''directories''' to the '''history''' directory.
# Write a Linux command to remove both directories named '''1''' and '''2'''.
# Write a Linux command to remove the '''concepts''' directory and its contents.
# Write a Linux command to remove the '''concepts''' directory and prompt the user if they want to remove this directory’s contents.
# Write a single Linux command to create the following empty files in the concepts directory:<br>'''myfile.txt'''<br>'''yourfile.txt'''<br>'''thefile.txt'''<br><br>
# Write a Linux command to view the contents of the myfile.txt text file to prove it is empty.<br>What is the difference between the commands: '''cat''', '''more''' and '''less'''?
# Write a Linux command to sort the contents of a file called '''uli101/customers.txt'''
# Write a Linux command to display the first 4 lines of a file called '''uli101/customers.txt'''
# Write a Linux command to display the last line of a file called '''uli101/customers.txt'''
# Write a Linux command to match a line containing the pattern '''Linux''' in a file called '''uli101/customers.txt'''
# Write a Linux command to display unique occurrences of consecutive lines in a file called '''uli101/customers.txt'''
# Create a '''table''' listing each Linux command, useful options that are displayed near the top of this tutorial labelled: '''Tutorial Reference Material'''


[[Category:ULI101]]