How to self-terminate a bash script after timeout?

bash process kill signals

39,161

Solution 1

If you always want the script to timeout after 5 minutes, you can simply use a block in a background process like this. If you use Ctrl+C while it's running, the background process will also terminate:

#!/bin/bash
{
    sleep 5m
    kill $$
} &

while true
do
    date
    sleep 1
done

Solution 2

The timeout utility that is a part of GNU coreutils does it for you:

timeout 5m bash script.sh

would terminate the script after 5 minutes of execution.

Solution 3

You get the PID with PID=$$.

What you want may be most easily achieved with the command timeout.

But you can run a background process, too:

(sleep $TIMEOUT && kill "$PID") &

Solution 4

You could change your loop to:

#!/bin/bash -
SECONDS=0
while ((SECONDS < 5*60))
do
  echo "line printed"
done

Or insert ((SECONDS < 5*60)) || exit within your deepest loop.

SECONDS in ksh, zsh and bash is a special variables that gets incremented every second.

Solution 5

You can use a check condition:

#!/bin/bash

START=$(date +%s)

while [[ $(($(date +%s) - $START)) -lt 300 ]]
do
    #do something here
done

echo QUIT

Explanation

date +%s get the time in seconds since epoch, we save it to START variable, mark start time of script.
[[ $(($(date +%s) - $START)) -lt 300 ]]: we get current time (date +%s again) subtract to start time (which is saved in START variable).
If the result is less than 300 (5 minutes), script continue running,
If the result is equal to or greater than 300, meaning script has run 5 minutes since start time, we quit the while loop, script ends.

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39,161

MLSC

Updated on September 18, 2022

Comments

MLSC over 1 year
I have a bash script doing a lot of things called script.sh:
```
#!/bin/bash
#It
#Is
#Doing
#Things
```
Is there a way that I can get the process ID of this script from within itself, and then kill it after 5 minutes?

Like:
```
#!/bin/bash
#Get pid of script.sh here, start a 5 minute timer and kill the script after time runs out
#It
#Is
#Doing
#Things
```
- n.st almost 10 years
  
  mywiki.wooledge.org/XyProblem ;)
- Lesto almost 10 years
  
  uset timeout, redirect output to a file (maybe in /tmp, if it is on ram you get better performance) and tail -f that file.
MLSC almost 10 years

Pardon but there is a problem..while my script is running it shows me output..but in your case this is not do that..Imagin you have infinitive while loop that echo sth...when I do what you said it doesn't show me output and my machine hangs...
MLSC almost 10 years

Pardon but there is a problem..while my script is running it shows me output..but in your case this is not do that..Imagin you have infinitive while loop that echo sth...when I do what you said it doesn't show me output and my machine hangs...
MLSC almost 10 years

Thank you..My script has infinitive loop...if I put my whole script into your while loop do you think it works? Thank you
cuonglm almost 10 years

I think you must use my while loop instead of your infinitive loop to make it works. Can you give more details about your script?
MLSC almost 10 years

+1 This is my script
Hauke Laging almost 10 years

@MortezaLSC I have given you two suggestions. What exactly have you done?
MLSC almost 10 years

see Gnouc's answer, This is my script and please see my update as well..Thank you very much
MLSC almost 10 years

You see...It brings my script to background...while my script is running it shows sth in terminal runtime..
Darkhogg almost 10 years

I think you still need to add & at the end to actually send it to the background. The brackets only start a subshell.
MLSC almost 10 years

I think your answer is one of the best one..but I would be thankful and your answer would be accepted if you help me, This is my script . Where should I put your aswer here? Thank you very much
user almost 10 years

Works fine for me. I made a script consisting mostly of while : ; do echo hello ; done then ran timeout 1s bash ./thatscript.sh -- it printed "hello" a large number of times and terminated after about a second, as expected.
MLSC almost 10 years

Your answer is the sth like Gnouc's answer and both are correct really...but in my case I confused...doesn't work
MLSC almost 10 years

Your answer is the sth like Stephane Chazelas's answer and both are correct really...but in my case I confused...doesn't work
MLSC almost 10 years

Thank you..this is a good answer but doesn't work in my case
Davide Norbiato almost 10 years

...Well, why not?
MLSC almost 10 years

Owww...I saw your edited answer now...This is working absolutely...Thank you very much...
MLSC almost 10 years

No..I put the whole script into your while loop with #!/bin/bash - and doesn't work as well...please see blujay's answer.. It is working well
MLSC almost 10 years

I tested it and My system broke down :), I don't know why!!!
devnull almost 10 years

@MortezaLSC I'm not sure what happens in your case. This is a pretty standard utility designed for the very purpose.
MLSC almost 10 years

Thank you very much @devnull . I used your answer and of course it is helping me...Thank you very much
Sergiy Kolodyazhnyy about 7 years

Didn't know such variable existed. As always, learned something new from your answers
django over 3 years

If you check via ps command , parent script and sleep are still running. Not recommended
Davide Norbiato over 3 years

@django It works as-described for me. Run the script, Ctrl+C, run ps, and the background sleep process is terminated.