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→INVESTIGATION 4: CONTROL FLOW STATEMENTS
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# Confirm that you are located in your '''home''' directory in your Matrix account.<br><br>
# Issue the following Linux commands at the Bash shell prompt to assign values to several variables:<br><span style="color:blue;font-weight:bold;font-family:courier;">course="ULI101"<br>number1=5<br>number2=10</span><br><br>You can test conditions by issuing '''Linux commands / pipeline commands''' <u>or</u><br>by using the '''test''' command. We will demonstrate using the '''test''' command in this tutorial,<br>and then demonstrate testing by issuing a ''Linux command / pipeline command'' in a <u>later </u> tutorial.<br><br>
# Issue the following Linux command to test a condition:<br><span style="color:blue;font-weight:bold;font-family:courier;">test $course = "ULI101"</span><br><br>The '''$?''' variable is used to store an '''exit status''' of the <u>previously-issued</u> command (including the test command).<br>If the exit status is '''zero''', then it indicates a ''TRUE'' value and if the status is '''non-zero''', then it indicates a ''FALSE'' value.<br><br>
# Issue the following Linux command to view the '''exit status''' of the previously-issued '''test''' command:<br><span style="color:blue;font-weight:bold;font-family:courier;">echo $?</span><br><br>Based on the ''exit status'' value, is the result ''TRUE'' or ''FALSE''?<br><br>