How to use the expr command: 2-Minute Linux Tips

The video tutorial introduces the EXPR command, which is used for performing mathematical and Boolean calculations on the command line. It covers basic operations like addition, division, and multiplication, highlighting the need for a backslash in certain cases. The tutorial also explains how to use EXPR for Boolean calculations and comparisons, demonstrating how to check if numbers are equal or if one is greater than another. Additionally, it discusses handling complex expressions and the importance of understanding operation precedence. The EXPR command can be used both on the command line and within scripts for variable comparisons.

What is the purpose of using a backslash in the EXPR command?

• To indicate multiplication

• To indicate division

• To indicate addition

• To indicate subtraction

In Boolean calculations using EXPR, what does a result of 0 indicate?

• The expression is false

• The expression is true

• The numbers are not equal

• The numbers are equal

How does EXPR determine if one number is greater than another?

• By using the addition operator

• By using the multiplication operator

• By using comparison operators

• By using the subtraction operator

Why is it important to be cautious with complex expressions in EXPR?

• Because they always result in errors

• Because they can give unexpected results due to operation order

• Because they are not supported in scripts

• Because they require additional software

What is one use of the EXPR command in scripts?

• To format text

• To delete variables

• To compare variables

• To create new files