Which option on the cron command is used to display entries in the current crontab?
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Cron is named after Greek word “Chronos” that is used for time. It is a system process that will automatically perform tasks as per the specific schedule. It is a set of commands that are used for running regular scheduling tasks. Crontab stands for “cron table”. It
allows to use job scheduler, which is known as cron to execute tasks. Crontab is also the name of the program, which is used to edit that schedule. It is driven by a crontab file, a config file that indicates shell commands to run periodically for the specific schedule. In this Operating system tutorial, you will learn: Here are the reasons for using Cronjobs in Linux: Linux
system pack has a useful task scheduler named crontab. Crontab is popular because it can be scheduled to run an automated process as root. Therefore, having an automated process running as root makes system changes easier. You just need to change the task and then wait until the task is re-initiated. Linux Crontab formatCrontab of Linux has six fields. The first five fields define the time and date of execution, and the 6’th field is used for command execution. Crontab syntax: [Minute] [hour] [Day_of_the_Month] [Month_of_the_Year] [Day_of_the_Week] [command] 
How to Add/Modify CrontabUser can edit their crontab jobs with the help of following crontab command: $ crontab -u -e The above command will open the personal crontab configuration of your computer system, which can be edited by using your default text editor. There is no need to restart your crontab as it will pick up your changes automatically when you use following command. $ crontab -l To remove your crontab tasks, use the following command. $ crontab -r To add or update job in crontab, use below given command. crontab -e Command to edit other user’s crontab crontab -u username -e How to List CrontabCommand to view crontab entries of current user crontab -l Command to view crontab entries of a specific user: crontab -u username -l Important Crontab ExamplesHere, are some important examples of Crontab
Summary:
Which command is used to display crontab?The crontab -l command displays the contents of a crontab file much the same way that the cat command displays the contents of other types of files. You do not have to change the directory to /var/spool/cron/crontabs directory (where crontab files are located) to use this command.
What is the use of * * * * * In cron?* * * * * is a cron schedule expression wildcard, meaning your cron job should run every minute of every hour of every day of every month, each day of the week.
Which command is used to display your cron jobs in Linux?You can use the cat, crontab and other Linux commands to view, list and display all cron jobs. The cron service searches its spool area (usually /var/spool/cron/crontabs) for crontab files (which are named after user accounts); crontabs found are loaded into memory.
Which command will you use to add an entry in cron file?Before You Begin. Create a new crontab file, or edit an existing file. $ crontab -e [ username ] ... . Add command lines to the crontab file. Follow the syntax described in Syntax of crontab File Entries. ... . Verify your crontab file changes. # crontab -l [ username ]. |
