Book Image

Linux Shell Scripting Essentials

By : Sinny Kumari, Khem Raj
Book Image

Linux Shell Scripting Essentials

By: Sinny Kumari, Khem Raj

Overview of this book

Table of Contents (15 chapters)
Linux Shell Scripting Essentials
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Managing the crontab entry


We don't add or modify an entry of a crontab directly. It is done by using the crontab command that allows you to add, modify, and list crontab entries. Each user can have their own crontab where they can add, delete, or modify tasks. By default, it is enabled for all users, but if a system administrator wants to restrict some of the users, he or she can add that user in the /etc/cron.deny file.

The syntax of using the crontab command is as follows:

crontab [-u user] file
crontab [-u user] [option]

The options of the crontab are explained in the following table:

Option

Description

-u user

Appends the name of the user whose crontab is to be modified

-l

Displays the current crontab on stdout

-e

Edit the current crontab using an editor specified by the EDITOR env

-r

Remove the current crontab

-i

Interactive removal of the current crontab when used with the -r option

Listing crontab entries

To list the crontab entries, we use the -l option for...