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→INVESTIGATION 2: ADDITIONAL LOOPING STATEMENTS
# When prompted, enter a letter instead of a number. What happens?<br>Does the shell script allow you to enter an invalid grade like '''200''' or '''-6'''?<br><br>Let's learn how to perform '''math operations''' in a shell script, and then incorporate math operations within a loop.<br><br>
# Use a text editor like vi or nano to create the text file called '''for-6.bash''' (eg. <span style="color:blue;font-weight:bold;font-family:courier;">vi for-6.bash</span>)<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="color:blue;font-weight:bold;font-family:courier;"><br>#!/bin/bash<br>value=1<br>while [ $value -le 5 ]<br>do<br> echo "$value"<br> value=value+1<br>done<br></span><br>
# Save your editing session and exit the text editor (eg. with vi: press '''ESC''', then type ''':wx''' followed by '''ENTER''').<br><br>
# Set execute permissions for this shell script and run your shell script by issuing: <span style="color:blue;font-weight:bold;font-family:courier;">./for-6.bash</span><br><br>What do you notice? You should have noticed an '''error message'''.<br><br>
