crontab按秒執行任務

/etc/crontab

# test-crontab按秒執行任務
* * * * * root echo $(date) >> /root/test.txt
* * * * * root sleep 5 && echo $(date) >> /root/test.txt
* * * * * root sleep 10 && echo $(date) >> /root/test.txt
* * * * * root sleep 15 && echo $(date) >> /root/test.txt
* * * * * root sleep 20 && echo $(date) >> /root/test.txt
* * * * * root sleep 25 && echo $(date) >> /root/test.txt
* * * * * root sleep 30 && echo $(date) >> /root/test.txt
* * * * * root sleep 35 && echo $(date) >> /root/test.txt
* * * * * root sleep 40 && echo $(date) >> /root/test.txt
* * * * * root sleep 45 && echo $(date) >> /root/test.txt
* * * * * root sleep 50 && echo $(date) >> /root/test.txt
* * * * * root sleep 55 && echo $(date) >> /root/test.txt

test.sh

#!/bin/bash
while true; do
	echo $(date)
	sleep 5
done