Bash $RANDOM

Written by Benjamin Cane on 2011-07-01

Found this cool little thing today when I was looking for a way to create a random number in BASH. It seems that BASH does the hard work for you and creates a variable called $RANDOM

# echo $RANDOM  
26031  
# echo $RANDOM  
20163  
# echo $RANDOM  
30045

And if you want to print off a certain range such as 0 - 100 you can do it like so.

# echo $((RANDOM%100))  
81

Figured I would share this as it is a cool little trick.


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Benjamin's specialty is keeping the lights on for mission critical systems. He is currently building applications that enable high concurrency financial transactions.

Recently Benjamin published his first book; Red Hat Enterprise Linux Troubleshooting Guide. In addition to writing, he has several Open Source projects focused on making Ops easier. These projects include Automatron, a project enabling auto-healing infrastructure for the masses.


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Identify, capture and resolve common issues faced by Red Hat Enterprise Linux administrators using best practices and advanced troubleshooting techniques

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