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→INVESTIGATION 2: ADDITIONAL LOOPING STATEMENTS
# Run your shell script by issuing: <span style="color:blue;font-weight:bold;font-family:courier;">./for-3.bash</span><br><br>What do you notice? How does the result differ from the shell script called for-2.bash. Why?<br><br>Let's create another shell script to run a loop for each file that is contained in your current directory using command substitution.<br><br>
# Use a text editor like vi or nano to create the text file called '''for-4.bash''' (eg. <span style="color:blue;font-weight:bold;font-family:courier;">vi for-4.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;">#!/bin/bash<br>clear<br>set $(ls)<br>echo Here are files in my current directory:"<br>echo<br>for x<br>do<br> echo " $x"<br>done</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>
# 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-4.bash</span><br><br>
# Run your shell script by issuing:<br><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>Does the shell script allow you to enter an invalid grade like 200 or -6?<br><br>
:In the next investigation, you will learn to create and test-out start-up files to customize your shell.
