Linux Job Managing

Introduction

Welcome to the enchanting land of MagicaLakeland, a serene place where the mystical waters of knowledge flow in abundance. As the sun dips below the horizon and dusk falls, the inhabitants of this magical realm resume their lifelong quests with a special vigour. Among them is Zara, a skilled sorceress, keeper of ancient lore and formidable Linux job manager. Zara recognises the power within the shell and commands it with grace to perform extraordinary feats, orchestrating an army of background processes like a symphonic dance around the celestial lake.

Your mission, should you accept it, is to help Zara manage the jobs on the Linux operating system. Throughout your journey, you'll learn to use the powerful commands to control processes, monitor background tasks and master job control to ensure the harmony of the lake. This journey will enchant you with the skills necessary to become a skilled Linux job manager yourself. The tranquility of the lake and the wisdom of Zara await your dedication.

Skills Graph

Starting and Managing Background Jobs

In this step, you'll learn how to start a process in the background and manage it using jobs. Zara has entrusted you with a magical spell script that needs to run without obstructing your console.

First, create the magical spell script named spell.sh in the ~/project directory:

touch ~/project/spell.sh
echo 'while true; do' > ~/project/spell.sh
echo 'echo "Casting spell in the background..."' >> ~/project/spell.sh
echo 'sleep 5' >> ~/project/spell.sh
echo 'done' >> ~/project/spell.sh

Next, make the script executable and run it in the background:

chmod +x ~/project/spell.sh
~/project/spell.sh &

The & character at the end of the command causes the script to run in the background.

To view all background jobs, use:

jobs

The output should be:

[1] + running ~/project/spell.sh

Foregrounding a Background Job

Maintaining control over background magic is crucial. In this step, you'll bring a background process to the foreground using fg. Zara believes that focusing on one task at a time engulfs the output with pure energy.

First, ensure you have a background job running with:

jobs

If [1] + running ~/project/spell.sh is not listed, start the spell.sh script in the background (refer to Step 1).

Bring the last background job to the foreground:

fg %1

This should bring spell.sh to the foreground and output:

[1] + 1123 running ~/project/spell.sh
Casting spell in the background...

Summary

In this lab, we embarked on a journey through the realm of MagicaLakeland to learn the magic of Linux task management. From casting spells in the background to bringing tasks to the forefront, we traversed the magical teachings of the lake with Zara. The skills you'll gain will enable you to maintain harmony in your own Linux environment and orchestrate tasks like a true wizard.

Through the practical implementation of managing background jobs and foregrounding tasks, we've put theory into action and demystified the arcane commands that Linux has to offer. I hope you found this lab both enriching and enchanting. May you take this knowledge with you and become a guardian of process management in your own right.