Managing Shell jobs

Job Management in Unix/Linux Shell

Introduction

• Users have the ability to manage their own jobs in the Unix/Linux shell. This includes starting, stopping, and moving jobs between foreground and background.

Starting a Job in the Background

• To start a command as a job in the background, append an ampersand (&) at the end of the command.

  • Example:

  • Command: sleep infinity &

  • This will run the command 'sleep' indefinitely as a background job.

Moving a Running Job to the Background

• If a job is currently running in the foreground, you can temporarily stop it by using the keyboard shortcut:

  • Control + Z

• To move the stopped job to the background, use the command:

  • bg

  • This command will resume the job in the background after it has been stopped.

Overview of Running Jobs

• The command jobs provides a complete overview of all currently running jobs, including their job numbers and statuses.

Moving a Job to the Foreground

• To move a job from the background back to the foreground, use the command:

  • fg [job number]

  • This command brings the specified job back to the foreground where it can be interacted with directly.

Examples

• Example of running a command:

  • Initial Command: sleep infinity

  • Result: Runs as a foreground job.

• To manipulate this job:

  • Stop the job: Control + Z

  • Move to background: bg

• Result: The job continues to run in the background.

Terminating a Job

• To terminate a job currently running in the foreground, use the keyboard shortcut:

  • Control + C

• This command sends an interrupt signal to the job, terminating it.

Conclusion

• The management of jobs in the Unix/Linux shell is a straightforward process involving stopping, starting, and manipulating jobs between foreground and background using simple commands and keyboard shortcuts.

• Users can effectively manage their shell environment by utilizing the commands bg, fg, jobs, and control signals like Control + Z and Control + C.