Skip to content

Quiz: Shell Scripting and Automation

Test your understanding of shell scripts, automation, and cron jobs.

1. What is a shebang and why is it important?

  1. A shell command for making noise
  2. The first line (#!/bin/bash) that tells the system which interpreter to use
  3. A debugging tool
  4. A type of variable
Show Answer

The correct answer is B. The shebang (like #!/bin/bash) is the first line of a script that tells the system which interpreter should execute it. Without it, the system may not know how to run your script properly.

Concept Tested: Script Shebang

See: Chapter 13 - Shebang

2. What must you do before running a shell script you created?

  1. Compile it
  2. Make it executable with chmod +x
  3. Convert it to binary
  4. Register it with the system
Show Answer

The correct answer is B. Shell scripts are text files and need execute permission to run directly. Use chmod +x script.sh to make it executable, then run with ./script.sh.

Concept Tested: Script Permissions

See: Chapter 13 - Making Scripts Executable

3. How do you access the first argument passed to a script?

  1. $0
  2. $1
  3. $first
  4. $arg1
Show Answer

The correct answer is B. In bash scripts, $1 is the first argument, $2 is the second, and so on. $0 is the script name itself, and $# is the count of arguments. $@ represents all arguments.

Concept Tested: Script Arguments

See: Chapter 13 - Script Arguments

4. What is cron used for?

  1. Compressing files
  2. Scheduling commands to run automatically at specified times
  3. Creating users
  4. Managing network connections
Show Answer

The correct answer is B. Cron is a time-based job scheduler that runs commands automatically at specified intervals. It's perfect for backups, log rotation, system maintenance, and any recurring tasks.

Concept Tested: Cron Daemon

See: Chapter 13 - Cron

5. In cron syntax, what does 0 2 * * * mean?

  1. Every 2 minutes
  2. At 2:00 AM every day
  3. Every 2 hours
  4. On the 2nd of every month
Show Answer

The correct answer is B. Cron fields are: minute, hour, day-of-month, month, day-of-week. So 0 2 * * * means minute 0, hour 2, every day of month, every month, every day of week = 2:00 AM daily.

Concept Tested: Cron Syntax, Cron Schedule Fields

See: Chapter 13 - Cron Syntax

6. What command edits your personal crontab file?

  1. nano /etc/cron
  2. crontab -e
  3. vi /var/cron
  4. edit crontab
Show Answer

The correct answer is B. crontab -e opens your personal crontab file for editing. Use crontab -l to list current cron jobs, and crontab -r to remove all your cron jobs.

Concept Tested: Crontab Command

See: Chapter 13 - Crontab Command

7. What does $? contain in a shell script?

  1. The current process ID
  2. The exit status of the last command
  3. The number of arguments
  4. The script filename
Show Answer

The correct answer is B. $? contains the exit status (return code) of the most recently executed command. A value of 0 typically means success, while non-zero values indicate various errors.

Concept Tested: Script Exit Codes

See: Chapter 13 - Exit Codes

8. What is the purpose of set -e at the beginning of a script?

  1. Sets the editor
  2. Exits the script immediately if any command fails
  3. Enables echoing of commands
  4. Sets environment variables
Show Answer

The correct answer is B. set -e makes the script exit immediately if any command returns a non-zero exit status. This helps catch errors early rather than continuing with a broken state.

Concept Tested: Script Best Practices

See: Chapter 13 - Script Safety

9. What does the at command do?

  1. Displays file attributes
  2. Schedules a one-time command for future execution
  3. Shows the current time
  4. Lists all files at a location
Show Answer

The correct answer is B. Unlike cron which runs recurring jobs, at schedules a one-time command for a specific future time. For example, at 3pm tomorrow lets you schedule a job for 3 PM tomorrow.

Concept Tested: At Command

See: Chapter 13 - At Command

10. What is the difference between * and */5 in a cron schedule?

  1. They're identical
  2. * means every time unit; */5 means every 5th time unit
  3. */5 runs 5 times longer
  4. * is invalid syntax
Show Answer

The correct answer is B. In cron, * means "every" (every minute, hour, etc.), while */5 means "every 5th." So in the minute field, * runs every minute while */5 runs at minutes 0, 5, 10, 15, 20, etc.

Concept Tested: Cron Syntax

See: Chapter 13 - Cron Examples