Read-Only Variables in Bash

Bash has a little known concept of read-only variables. When specifying 'readonly' during a variable assignment prevents the variable from being reassigned. For example; 1 #!/bin/bash 2 3 readonly x=0 4 echo $x 5 x=1 6 echo $x Line 3 specifies a read-only assignment of variable x to 0, an attempt to reassign on line 5 will be disregarded and produce an error message. The error doesn't prevent…