Linux Shell Scripting Cookbook - Third Edition

How to do it...

1. A numeric value is assigned to a variable the same way strings are assigned. The value will be treated as a number by the methods that access it:

        #!/bin/bash
        no1=4;
        no2=5;

2. The let command is used to perform basic operations directly. Within a let command, we use variable names without the $ prefix. Consider this example:

        let result=no1+no2
        echo $result

                  Other uses of let command are as follows:

• Use this for increment: 

                $ let no1++

• For decrement, use this:

                $ let no1--

• Use these for shorthands:

                let no+=6
                let no-=6

                These are equal to let no=no+6 and let no=no-6, respectively.

• Alternate methods are as follows:

              The [] operator is used in the ...