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Tutorial12: Shell Scripting - Part 2

65 bytes added, 09:01, 5 September 2020
INVESTIGATION 2: ADDITIONAL LOOPING STATEMENTS
# Use the '''more''' command to view the contents of the text file called '''for-1.bash''' (eg. <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 from an executed shell script.<br>We will revisit this now.<br><br>You can also use the for loop with a list using '''command substitution''' - this is an effective technique to loop within a shell script.<br><br>
# FirstBefore creating a new shell script, you need to let's learn how to use command substitution from the Bash Shell to store arguments as positional parametersand use them for practice.<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?<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>
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