Sometimes you might need to run some command from the Linux command line and repeat it several times.
There is a simple way to write a command once and have it executed N times using Bash loop FOR.
In this short note you’ll find how to execute some command a number of times in a row.
The best way to run a command N times is to use loop FOR in Bash.
Cool Tip: The same loop can be used for a mass mail sending! Send bulk emails from the Linux command line to test your mail server! Read more →
Use the following syntax to run some command 5 times:
for n in {1..5}; do <COMMAND>; done
Let’s help Bart Simpson to fill a chalkboard:
$ for n in {1..5}; do echo "I WILL NOT SKATEBOARD IN THE HALLS"; done
I WILL NOT SKATEBOARD IN THE HALLS
I WILL NOT SKATEBOARD IN THE HALLS
I WILL NOT SKATEBOARD IN THE HALLS
I WILL NOT SKATEBOARD IN THE HALLS
I WILL NOT SKATEBOARD IN THE HALLS
Cool Tip: Run commands on a remote Linux server over SSH and get the results locally! Read more →
If you often need to use such construction from the Linux command line, you can create the following Bash function (add to your ~/.bashrc):
function run() {
number=$1
shift
for n in $(seq $number); do
$@
done
}
Usage:
$ run 5 <COMMAND>
Cool Tip: Every Linux administrator must know how to read a file line by line with a Bash WHILE loop! Read more →
Example:
$ run 5 echo "I WILL NOT SKATEBOARD IN THE HALLS" I WILL NOT SKATEBOARD IN THE HALLS I WILL NOT SKATEBOARD IN THE HALLS I WILL NOT SKATEBOARD IN THE HALLS I WILL NOT SKATEBOARD IN THE HALLS I WILL NOT SKATEBOARD IN THE HALLS
Article Number: 481
Posted: Mon, Feb 18, 2019 2:26 PM
Last Updated: Mon, Feb 18, 2019 2:26 PM
Online URL: http://kb.ictbanking.net/article.php?id=481