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→Using Control Flow Statements in Shell Scripts
<table align="right"><tr valign="top"><td>[[Image:test-1.png|thumb|right|140px|Examples of simple comparisons using the test command.]]</td><td>[[Image:test-2.png|thumb|right|140px|Examples of using additional comparisons using the test command.]]</td></table>
'''Control Flow Statements''' are used to make your shell scripts<br>more '''flexible''' and can '''adapt''' to changing situations.<br><br>In order to use control flow statements, you need to test a condition to get a <br>'''TRUE ''' (zero value) or '''FALSE ''' (non zero value). This can be done two ways:<ul><li>Run a command to get the exit status (<span style="font-family:courier;font-weight:bold;">$?</span>)</li><li>Use the '''test''' command</li></ul><br>Refer to the diagrams on the right to see how to use the test command.<br><br>
You CANNOT use the <span style="font-family:courier;font-weight:bold;"><</span> or <span style="font-family:courier;font-weight:bold;">></span> symbols when using the test command since these are redirection symbols. Instead, you need to use options when performing numerical comparisons.
