We can use the expr command for arithmetic operations. The expr command is an external command; the binary of the expr command is stored in the folder called /usr/bin/expr.
Perform an addition operation as follows:
$ expr 40 + 2 42
Perform a subtraction operation as follows:
$ expr 42 - 2 40
Perform a division operation as follows:
$ expr 40 / 10 4
Perform a modulus (getting remainder) operation as follows:
$ expr 42 % 10 2 $ expr 4 * 10 expr: syntax error
With the expr command, we cannot use * for multiplication. We need to use * for multiplication:
$ expr "4 * 10" 4 * 10 $ expr 4 * 10 40
We will write a simple script to add two numbers. Write the shell script, arithmetic_01.sh as follows: ...