First we will see what is Array in Linux
If you have been doing shell scripting, you must have definitely came across the term called variable. So when you use a variable, you can add a single name to the variable – In other words one variable can hold only one value.
Example of an Variable
#!/bin/bash
cityname="Berlin"
echo "$cityname"So if you want to hold names of multiple cities, then you will have to create new variable for each city.
For an Example
cityname01="Berlin"
cityname02="Tokyo"
cityname03="Moscow"
cityname04="Rio"
cityname05="Denver"However, to ease life we could use a single Array which could hold up all values in a single variable.
To define Array :-
cityname[0]="Berlin"
cityname[1]="Tokyo"
cityname[2]="Moscow"
cityname[3]="Rio"
cityname[4]="Denver"So here we have stored all city Names in a Array called “cityname”. So now question is how do you access an Array.
You just need to echo it’s number 🙂 Like shown below.
#!/bin/bash
cityname[0]="Berlin"
cityname[1]="Tokyo"
cityname[2]="Moscow"
cityname[3]="Rio"
cityname[4]="Denver"
echo "${cityname[3]}"So above script will print “Rio” If you want to print all city names then you would use
echo "${cityname[@]}"
OR
echo "${cityname[*]}"You can copy paste the script below and run it which will help you understand better.
#!/bin/bash
cityname[0]="Berlin"
cityname[1]="Tokyo"
cityname[2]="Moscow"
cityname[3]="Rio"
cityname[4]="Denver"
echo Cities I love are : "${cityname[@]}"
Output would be.
Cities I love are : Berlin Tokyo Moscow Rio Denver