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→INVESTIGATION 4: USING CONTROL FLOW STATEMENTS
# Issue a linux command to display the value of '''$?'''.<br>You should notice that the exit status value is now FALSE which is the correct result.<br><br>
# The '''test''' command can be abbreviated by the square brackets '''[ ]''' which contain the test condition within the square brackets. You need to have spaces between the brackets and the test condition; otherwise, you will get a test error.<br><br>
# To generate a '''test error''', copy and paste the following '''test''' command:<br><span style="color:blue;font-weight:bold;font-family:courier;">[$number1 -gt $number2]</span><br><br>You should notice an The reason for the error was that you need spaces between the square brackets and the test error messagecondition.<br><br># Copy and paste the following (correct) '''test''' command:<br><span style="color:blue;font-weight:bold;font-family:courier;">[ $number1 -gt $number2 ]</span><br><br># Issue a command to view the value of the '''exit status ''' of the previously issued '''test''' command. <br>You should notice that is works properly.<br><br>'''Let's now learn about control-flow statements:'''<br><br>'''Logic statements''' are used to create different paths or directions based on the result of testing conditions. In this tutorial, we will only focus on the '''if''' logic statement.<br><br>
# Use a text editor like vi or nano to create the text file called '''if-1.bash''' (eg. <span style="color:blue;font-weight:bold;font-family:courier;">vi if-1.bash</span>)<br><br>If you are using the nano text editor, refer to notes on text editing in a previous week in the course schedule.<br><br>
# Enter the following lines in your shell script:<br><span style="font-family:courier;font-weight:bold;">#!/bin/bash<br>clear<br>num1=5<br>num2=10<br>if [ $num1 -gt $num2 ]<br>then<br> echo "Greater Than"<br>fi</span><br><br>
