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→Using Control Flow Statements in Shell Scripts
<table align="right"><tr valign="top"><td>[[Image:test-1.png|thumb|right|150px|Examples of simple comparisons using the test command.]]</td><td>[[Image:test-2.png|thumb|right|150px|Examples of using additional comparisons using the test command.]]</td></table>Control Flow Statement are used to make your shell scripts more flexible and can adapt to changing situations.
The special parameter $? Is used to determine the exit status of the previously issued Linux command. �
The exit status will either display a zero (representing TRUE) or a non-zero number (representing FALSE). This can be used to determined if a Linux command was correctly or incorrectly executed.
The '''test''' Linux command is used to test conditions to see if they are '''TRUE''' (i.e. value '''zero''') or '''FALSE''' (i.e. value '''non-zero''') so they can be used with control flow statements to control the sequence of a shell script.
