How to add a crontab job to crontab using a bash script?

Question

I tried the below command and crontab stopped running any jobs: echo "@reboot /bin/echo 'test' > /home/user/test.sh"| crontab -

What is the correct way to script adding a job to crontab in linux?

Answer 1

I suggest you read Cron and Crontab usage and examples .

And you can run this:

➜ ( printf -- '0 4 8-14 * *  test $(date +\%u) -eq 7 && echo "2nd Sunday"' ) | crontab
➜  crontab -l
0 4 8-14 * *  test $(date +\0) -eq 7 && echo "2nd Sunday"            

Or

#!/bin/bash
cronjob="* * * * * /path/to/command"
(crontab -u userhere -l; echo "$cronjob" ) | crontab -u userhere -

Hope this helps.