How to use variables in a BASH shell script

Here’s how to use simple variables in BASH shell scripts. It appears there are no data types, and everything’s a string (correct me if I’m wrong). We can define a variable by first setting it to a value, then later refer to that value with a dollar sign in front of the variable name.

Here’s an example:

#!/bin/bash

VARIABLE="Testing"
echo $VARIABLE

Note that there are no spaces between the variable name, the equal sign or the value. Adding those will result in a runtime error.

Variables can be defined in upper or lower case letters, or a combination thereof.

BASH Variables have a global scope, unless they are prefaced with the local keyword inside functions (in which case, only said function will have access to its value).





Jay is founder of WP Hosting, a boutique style managed WordPress hosting and support service. He has been working with Plesk since version 9 and is a qualified Parallels Automation Professional. In his spare time he likes to develop iOS apps and WordPress plugins, or drawing on tablet devices.

He blogs about his coding journey at http://wpguru.co.uk and http://pinkstone.co.uk.

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