Linux crontab-r causes and solutions to no crontab for root

How to use:
crontab file [-u user]-replaces the current crontab with the specified files.
Crontab-[-u user]-replaces the current crontab with standard input.
crontab-1[user]-lists the user's current crontab.
crontab-e[user]-Edit user's current crontab.
crontab-d[user]-Delete the user's current crontab.
Crontab-c dir-Specifies the directory for crontab.
Format of the crontab file: M H d M D cmd.
Crontab-r: Delete the current schedule table
Crontab-l: List the current schedule s

Using crontab

-R is to delete the current user's timetable, causing
Crontab-l error no crontab for root
Workaround: Add a scheduled task file to the current user crontab-u root/var/log/


When you execute a shell script to schedule a task:
/bin/bash^m:bad interpreter:no such file or directory

The solution to this problem is because the shell script's document is not in the correct format

View the document format for the shell document: set FF?

The document format for setting up the shell document is: set Ff=unix

Linux crontab-r causes and solutions to no crontab for root