Logical 'OR' Operator | Shell Scripting
This is a multipart blog article series where I am going to explain the concepts of shell scripting and how to write a shell script in Linux, UNIX or Mac based systems. You can also follow this tutorial blog using windows but for that you have to install a bash from.
In this article we will see that how can we use ‘OR operator with the help of if condition. We will also see that different ways to use ‘OR’ operator.
We are going to use OR operator with if condition to solve a problem.
- If the age is greater than
18OR less than
`30, then it will be true/ successful and we will print “valid age”
- Otherwise it will give false.
- The syntax of if condition for this problem will be
if [ “$<variable_name>” –gt ] || [ “$<variable_name>” –lt 30 ]
ORoperator is used then if only one condition is true, then also it will return true.
- Another way to use
ORoperator is like this
if [ “$<variable_name>” –gt –o “$<variable_name>” –lt 30 ]
- In this way we use
-oflag and it work same as
||but the syntax to write the if condition is changed little bit.
- If you want to use
||operator then there is one more way to do and that is by using double square brackets like this
if [[ “$<variable_name>” –gt 18 || “$<variable_name>” –lt 30 ]]
So this was all about logical OR operator with if condition. Hope you liked it and learned something new from it.
If you have any doubt, questions, quires related to this topic or just want to share something with me, than please feel free to contact me.