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I added a cron job , but I found that even set * * * * * ~my_cronjob , it only only it at EVERY MINUTE , if I want it run at every 20 second , can advise what can i do ? thx
#!/bin/bash
while true
do
/path/to/command&
pid=$!
sleep 20
kill -SIGKILL $pid
done
This will also abort the process if it hasn't ended after 20 seconds.
Just to remind ust if they take this type of approach, don't put this script in as a cron job or you'll be starting a new one every minute that sleeps every 20 seconds.. etc. You'd soon have a gazillion of these spawned off and running..
The only modifications I made to the script was these:
I added an ampersand at the end of the command. That automatically starts it on the background, so the stdin doesn't lock and the script continues running.
I capture the pid of the process.
I added a line to kill it after sleeping for 20 seconds.
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