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→INVESTIGATION 2: ADDITIONAL LOOPING STATEMENTS
# Issue the following linux command to add execute permissions for your shell script:<br><span style="color:blue;font-weight:bold;font-family:courier;">chmod u+x for-5.bash</span><br><br>
# Run your shell script by issuing: <span style="color:blue;font-weight:bold;font-family:courier;">./for-5.bash</span><br><br>What do you notice? Does the output for this shell script differ than for-4.bash? Why?<br><br>The last thing in this section is to introduce you to '''error-checking'''.<br><br>
# Use the '''more''' command to view the text file called '''if-5.bash''' (eg. <span style="color:blue;font-weight:bold;font-family:courier;">more if-5.bash</span>)<br><br>Take a few moments to re-familiarize yourself with this shell script<br><br>
# Run your shell script by issuing: <span style="color:blue;font-weight:bold;font-family:courier;">./if-5.bash </span><br><br>When prompted, enter a letter instead of a number. What happens?<br><br>Let's edit the if-5.bash shell script to perform error-checking to force the user to enter a numeric value between 0 and 100.<br><br>
# Use a text editor like vi or nano to edit the text file called '''if-5.bash''' (eg. <span style="color:blue;font-weight:bold;font-family:courier;">vi if-5.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>
# Add the following lines in your shell script <u>AFTER<u> the read statement to prompt the user for a mark:<br><span style="font-family:courier;">#!/bin/bash<br>clear<br>echo Here are files in my current directory:"<br>echo<br>for x in $(ls)<br>do<br> echo " $x"<br>done<br></span><br><br>
# Save your editing session and exit the text editor (eg. with vi: press '''ESC''', then type ''':wx''' followed by '''ENTER''').<br><br>
# x
