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→INVESTIGATION 1: BASICS OF REDIRECTION
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">cat listing.txt cars murray 2> result.txt</span><br><br>What information does the '''result.txt''' file contain?<br><br>
# Issue the following Linux command: <span style="color:blue;font-weight:bold;font-family:courier;">cat listing.txt cars murray > myoutput.txt 2> result.txt</span><br><br>What is displayed on the monitor? what do those files contain?<br><br>The '''Here Document''' allows you to redirect stdin from with the Linux command itself. Let's get some practice using the Here Document.<br><br>
# Issue the following Linux command: <br><span style="color:blue;font-weight:bold;font-family:courier;">cat <<+<br>line 1<br>line 2<br>line 3<br>+</span><br><br>What do you notice?<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>
:The problem with using redirection to create files, you have these files taking up space, which requires you remove them. In the next investigation, you will be learning how to issue pipeline commands which can provide information by issuing several Linux commands without creating temporary files.<br><br>
