Operators in shell script

Continuation “https://samhith1053.medium.com/basics-of-shell-scripting-b4d0701d68a0”

Operators in shell script:

Arithmetic operators:

Arithmetic operators in shell script are (Addition(+),Subtraction(-), Multiplication(*),Division(/),Modulus(%))

We can implement arithmetic operators in 2 ways

1. Using subshell
2. Using expr expression

Using Subshell:

Using read we read the input from the user

$(($a+$b)) — — it creates a subshell and compute the value of a+b and again return to the parent shell

Using expr expression:

Note: There should be space between the operand and operator while using expr with reverse quotations

Relational Operators:

The relational operators in shell script is as follows

-lt stands for less than

-le stands for less than or equal to

-gt stands for greater than

-ge stands for greater than or equal to

-eq stands for equal to

-ne stands for not equal to

Logical Operators:

Logical operators are used to validate multiple conditions in a statement.

The main logical operators are

AND denoted by ‘-a’ in shell script . It produces true only if all the conditions in a statement are true

OR denoted by ‘-o’ in shell script. It produces true if any conditions in a statement is true

NOT denoted by ‘-n in shell script. If the statement is true then not output will be false. If the statement is false then not produces true