Arithmetic in Linux Shell Script
By: Vivek G.
Use to perform arithmetic operations.
Syntax:
expr op1 math-operator op2
Examples:
$ expr 1 + 3
$ expr 2 - 1
$ expr 10 / 2
$ expr 20 % 3
$ expr 10 \* 3
$ echo `expr 6 + 3`
Note:
expr 20 %3 - Remainder read as 20 mod 3 and remainder is 2.
expr 10 \* 3 - Multiplication use \* and not * since its wild card.
For the last statement not the following points
(1) First, before expr keyword we used ` (back quote) sign not the (single quote i.e. ') sign. Back quote is generally found on the key under tilde (~) on PC keyboard OR to the above of TAB key.
(2) Second, expr is also end with ` i.e. back quote.
(3) Here expr 6 + 3 is evaluated to 9, then echo command prints 9 as sum
(4) Here if you use double quote or single quote, it will NOT work
For e.g.
$ echo "expr 6 + 3" #
It will print expr 6 + 3
$ echo 'expr 6 + 3' # It
will print expr 6 + 3
Archived Comments
Comment on this tutorial
- Data Science
- Android
- AJAX
- ASP.net
- C
- C++
- C#
- Cocoa
- Cloud Computing
- HTML5
- Java
- Javascript
- JSF
- JSP
- J2ME
- Java Beans
- EJB
- JDBC
- Linux
- Mac OS X
- iPhone
- MySQL
- Office 365
- Perl
- PHP
- Python
- Ruby
- VB.net
- Hibernate
- Struts
- SAP
- Trends
- Tech Reviews
- WebServices
- XML
- Certification
- Interview
categories
Related Tutorials
smskannel SMS gateway run in background
Running jar files in background in ssh window
Can't locate ExtUtils/MakeMaker.pm in @INC ...
Could not open '': No such file or directory at lib/ExtUtils/MM_Unix.pm line 2697
make: Nothing to be done for `all'.
How to burn your CD / DVD ISO image using Nero Burning ROM (Ahead Software) on Windows
How to burn your CD / DVD ISO image using Media Creator (Adaptec/Roxio) on Windows
How to burn your CD / DVD ISO image using Nero Express (Ahead Software) on Windows
How to burn your CD / DVD ISO image using NISO Recorder V2 Power Toy on Windows
Compiling and Installing software from source in Linux