Linux Shell Scripting Cookbook - Second Edition

Arrays and associative arrays

Arrays are a very important component for storing a collection of data as separate entities using indexes. Regular arrays can use only integers as their array index. On the other hand, Bash also supports associative arrays that can take a string as their array index. Associative arrays are very useful in many types of manipulations where having a string index makes more sense. In this recipe, we will see how to use both of these.

Getting ready

To use associate arrays, you must have Bash Version 4 or higher.

How to do it...

1. An array can be defined in many ways. Define an array using a list of values in a line as follows:

   array_var=(1 2 3 4 5 6)
   #Values will be stored in consecutive locations starting from index 0.
   

   Alternately, ...