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Tutorial12: Shell Scripting - Part 2

32 bytes added, 18 March
INVESTIGATION 2: ADDITIONAL LOOPING STATEMENTS
# Issue the following Linux command to view the <span style="font-family:courier;font-weight:bold;">~/for-1.bash</span> file:<br><span style="color:blue;font-weight:bold;font-family:courier;">more ~/for-1.bash</span>)<br><br>As you should have noticed from ''tutorial 10'' that the '''for''' loop can use a '''list'''.<br>You can also use the for loop with positional parameters stored as '''arguments'''<br>from an executed shell script.<br><br>You can also use the for loop with a list using '''command substitution'''.<br>Using command sustitution is an effective method to loop within a shell script.<br><br>Before creating a new shell script, let's learn to use command substitution from the Bash Shell<br>to store arguments as positional parameters and use them for practice.<br><br>
# Issue the following linux command to set positional parameters in your current shell:<br><span style="color:blue;font-weight:bold;font-family:courier;">set apples oranges bananas pears</span><br><br>
# Issue the following linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">echo $#</span><br><br>What do you notice? What does this value represent?<br><br>
# Issue the following linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">echo $*</span><br><br>What do you notice?<br><br>These positional parameters could be used with a for loop. To simplify things, let's create another shell script that uses '''command substitution''' and a '''for''' loop.<br><br>
# Use a text editor like vi or nano to create the text file called '''for-3.bash''' (eg. <span style="font-weight:bold;font-family:courier;">vi for-3.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>
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