Water NB wrote:
> As a non-root account, I know how to do cron task.
> write a crontab file and call crontab program.

If you want to edit your (non-root) crontab, try:

crontab -e


> But for root:
> Where is this crontab file?
> i.e. Where /etc/{daily,weekly,...} are called?

If you have sudo, try:

sudo crontab -e

..and you'll get $EDITOR with the crontab of root.

If you don't have sudo, use su(1) and afterwards `crontab -e'.


Kind regards,

Petar