Bash While True

Bash While True is a bash While Loop where the condition is always true and the loop executes infinitely.

This kind of infinite loop is used to continuously execute a task, or continuously wait for an events to happen, etc.

In this tutorial, we will learn how to write a While True loop, with example bash scripts.

Sytnax

The syntax of While loop with condition always true is spaceman slot

</>
Copy
while true
do
    statement(s)
done

Examples

While True

In the following script, we print integers from 0 indefinitely using While True loop.

Example.sh

</>
Copy
i=0

while true
do
   echo "$i"
   let i++
done

Output

0
1
2
3
...

While True with Sleep

If we are using While True statement to run the loop indefinitely, and if we would like insert a small pause between loop executions to avoid a CPU load, use sleep command with required amount of time to sleep between iterations. slot garansi kekalahan

Example.sh

</>
Copy
i=0

while true
do
   echo "$i"
   let i++
   sleep 1
done

Output

0
1
2
3
...

Now, there is at least one second gap between iterations, since we have given sleep 1 command.

Conclusion

In this Bash Tutorial, we have learnt how to run while loop indefinitely using While loop statement with condition as true.