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|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>

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* [http://man7.org/linux/man-pages/man1/tee.1.html tee]<br>

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=INVESTIGATION 1: BASICS OF REDIRECTION=

In this investigation, you will learn how to redirect '''standard input''', '''standard output''' and '''standard error''' when issuing Unix / Linux commands.

# Press <span style="color:blue;font-weight:bold;font-family:courier;">ctrl-d</span> to exit the command.<br><br>

# Issue the '''cat''' command to view the contents of the file: '''output3.txt'''<br><br>

# Issue the '''cat''' command to view the contents of the '''cars''' file.<br><br>

# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">cut -c1-10 cars</span><br><br>What did this command do?<br><br>

# Issue the following Linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">grep 2 <<+<br>line 1<br>line 2<br>line 3<br>+</span><br><br>What do you notice? How does this differ from the previous command? Why?<br><br>

# Issue the following Linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">grep 2 > line2.txt <<+<br>line 1<br>line 2<br>line 3<br>+</span><br><br>What do you notice? What is contained in the file '''line2.txt'''? Why?<br><br>'''NOTE:''' You will now run a shell script to confirm that you properly issued Linux commands using redirection.<br><br>

# If you encounter errors, make corrections and '''re-run''' the checking script until you receive a congratulations message, then you can proceed.<br><br>

# Issue the '''ls''' command to see all of the '''temporary files''' that were created as a result of redirection.<br><br>The problem with using these redirection symbols is that you create '''temporary text files''' that take up '''space''' on your file system.<br><br>

# Issue a Linux command (using '''Filename Expansion''') to '''remove''' those temporary text files in the current directory.<br><br>

# If you encounter errors, make corrections and '''re-run''' the checking script until you receive a congratulations message, then you can proceed.<br><br>

# Issue the '''ls''' command to view the contents of this redirectory.<br><br>What did you notice?<br><br>

# View the <u>contents</u> of the '''text files''' that were created to see how the '''tee''' command<br>was used in the previous pipeline command.<br><br>What was the purpose of using the '''tee''' command for this pipeline command?<br><br>You will now run a shell script to confirm that you properly issued that Linux pipeline command<br>using the '''tee''' command and redirection.<br><br>

# Change to <u>your</u> '''home''' directory.<br><br>

# Remove the '''~/redirect''' directory and its contents.<br><br>

# Issue a Linux command to view the contents of the file called '''output.txt'''<br><br>What does ''grouping'' do when issuing multiple Linux commands (separated by a semi-colon ";") that uses redirection?<br><br>

# Issue the following Linux pipeline command (using \ at the end of most lines):<br><span style="color:blue;font-family:courier;font-weight:bold">echo "This will be split over multiple \<br>lines. Note that the shell will realize \<br>that a pipe requires another command, so \<br>it will automatically go to the next line" |tr '[a-z]' '[A-Z]'</span><br><br>Did the command work? What is the purpose of issuing a Linux command in this way?<br><br>

<br><br>

The purpose of this section is to obtain '''extra practice''' to help with '''quizzes''', your '''midterm''', and your '''final exam'''.

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).