expr

An expression calculation tool

Supplementary instructions

expr command is an expression calculation tool, use it to complete the evaluation operation of expressions.

Common operators for expr:

• Addition operation: +

• Subtraction operation: -

• Multiplication operation: \*

• Division operation: /

• Modulo (remainder) operation: %

grammar

expr(option)(parameter)

Options

--help: Display help information for the command;
--version: Display command version information.

Parameters

Expression: An expression that requires a value.

Example

result=`expr 2 + 3`
result=$(expr $no1 + 5)