Bash Shell Scripting - "cron" Command

This video tutorial covers the basics of scheduling jobs using Cron, focusing on crontab commands and their functionalities. It demonstrates how to create, edit, and manage crontab entries, including scheduling scripts and handling log files. The tutorial also addresses common mistakes, such as file overwriting, and provides solutions for troubleshooting script issues. Additionally, it explains how each user has their own crontab and how to manage these entries effectively.

What is the primary purpose of the 'echo_hello' script?

• To display the current date and a greeting

• To list all files in a directory

• To delete temporary files

• To create a new directory

What command is used to list crontab entries for a user?

• crontab -e

• crontab -l

• crontab -r

• crontab -a

Why is it important to specify the full path in a crontab entry?

• To prevent syntax errors

• To ensure the script runs in the correct directory

• To reduce memory usage

• To increase the execution speed

What is the effect of using a single '>' in a crontab entry?

• It deletes the file

• It appends output to a file

• It overwrites the file with new output

• It creates a new file

How can you modify a crontab entry to append output instead of overwriting?

• Use '<<' instead of '>'

• Use '>>' instead of '>'

• Use '||' instead of '>'

• Use '>' instead of '>>'

What should be done to ensure a script runs in the intended directory?

• Use absolute paths

• Use environment variables

• Use symbolic links

• Use relative paths

What is the purpose of the 'dummy_script.sh' version two?

• To delete files in the directory

• To execute commands in the specified directory

• To execute commands in the home directory

• To create a backup of the directory

How can standard error be redirected to the same file as standard output in crontab?

• By using '1>2'

• By using '2>1'

• By using '2>&1'

• By using '1>&2'

What command is used to delete all crontab entries for a user?

• crontab -c

• crontab -x

• crontab -r

• crontab -d

What is a key feature of crontab regarding user management?

• All users share a single crontab

• Each user has their own crontab

• Only administrators can create crontabs

• Crontabs are only available on weekends