Korn Shell: Unix and Linux Programming Manual, Third Edition, The

Control Commands

The Korn shell provides a number of control-flow commands typically found in high-level programming languages. The following sections cover these special commands.

The case Command

The case command provides multiple-branch capability. It is used to compare a single value against a number of other values. Commands associated with that value are executed when a match is made. The syntax for the case command is:

						case
						value
						in
						pattern1)
						command
						command;; 
       pattern2)
						command
						command;; 
       . . . 
       patternn)
						command
						command;; 
esac
					

where value is compared to pattern1, pattern2, ... patternn. When a match is found, the commands associated with that pattern up to the double semi-colons are executed.

The following Korn shell script demonstrates ...