Linux and Unix Shell Programming

17.4. Testing numbers

To test for numbers a different sort of operators are at our disposal. The general format is:

"number" numeric_operator "number" 

or

[ "number" numeric_operator "number" ] 

where the numeric_operator can be:

-eq	The two numbers are equal
-ne	The two numbers are not equal
-gt	The first number is greater than the second number
-lt	The first number is less than the second number
-le	The first number is less than or equal to the second number
-gt	The first number is greater than or equal to the second number

Both the following examples returns the same result. To test if a number is equal to another number (in this case is 130 equal to 130):

						$ NUMBER=130 
$ [ "$NUMBER" -eq "130" ] 
$ echo $? 
0
					

Phew! I’m glad that one returned ...