Shulou(Shulou.com)06/01 Report--

This article mainly explains the "what is the use of the Linux expr command", the content of the explanation is simple and clear, easy to learn and understand, the following please follow the editor's ideas slowly in depth, together to study and learn "what is the use of the Linux expr command" bar!

Linux common command expr command is a manual command line counter, used to calculate the value of expression variables under UNIX/LINUX, generally used for integer values, can also be used for strings.

Syntax expr expression expression description:

Separate each item with a space

Use a backslash\ to precede a specific shell character

Enclose strings containing spaces and other special characters in quotation marks

Example 1. Calculate the string length

> expr length "this is a test" 142, grab string

> expr substr "this is a test" 3 5 is is3, grab the location of the first character numeric string

Expr index "sarasara" a 24, integer operation

> expr 14% 9 5 > expr 10 + 10 20 > expr 1000 + 1900 > expr 30 / 3 / 25 > expr 30\ * 3 (when using a multiplication sign, its specific meaning must be masked with a backslash. Because shell may misunderstand the meaning of the asterisk) 90 > expr 30 * 3 expr: Syntax error thank you for reading, the above is the "what is the use of the Linux expr command" content, after the study of this article, I believe you have a deeper understanding of the use of the Linux expr command what this problem, the specific use of the need for you to practice verification. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.