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Tutorial12: Shell Scripting - Part 2

221 bytes added, 21 March
INVESTIGATION 3: exit AND break STATEMENTS
# Save your editing session and exit the text editor (eg. with vi: press '''ESC''', then type ''':x''' followed by '''ENTER''').<br><br>
# '''Add execute permissions''' for this Bash shell script.<br><br>
# Issue the following command (without arguments):<br><span style="color:blue;font-weight:bold;font-family:courier;">./exit.bash</span><br><br>What did you notice?<br><br>Since there are no arguments, the test within the running shell script returns FALSE,<br>then an '''error message''' with feedback of how to properly issue the shell script with an argument<br>and then '''terminates''' the Bash shell script.<br><br>Notice that the '''$0''' positional parameter displays the name of the currently running shell script in the USAGE message. This is useful in case you decide to change the name of the shell script at a later time.<br><br>The symbol '''&gt;&amp;2''' redirects '''standard output''' from the USAGE message<br>to '''standard error''' making like a <u>real</u> error message.<br>This "''neat redirection trick''" will NOT be considered for evaluation for this coverage.<br><br>
# Issue the following Linux command:<br><span style="color:blue;font-weight:bold;font-family:courier;">echo $?</span><br><br>What does this '''exit status''' from the previously issued command indicate?<br><br>
# Issue the following command (with an argument):<br><span style="color:blue;font-weight:bold;font-family:courier;">./exit.bash uli101</span><br><br>What did you notice this time?<br><br>
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