Running processes in the background is a common task when you are working with Linux. The operating system provides a powerful job control mechanism that allows you to keep multiple processes running simultaneously. This blog post will guide you on how to background a process in Linux.
What is a Background Process?
A background process is a computer process or task that is run behind the scenes (i.e., in the background) and without user intervention. These background processes can keep running while the user is not logged on or while another program is being run in the foreground.
Backgrounding a Process
Let’s look at how to background a process. One of the simplest ways to background a job in Linux is by appending the & operator at the end of your command. This operator tells the shell to execute the command in the background.
$ command &
Foreground to Background
If you’ve started a process in the foreground, it’s still possible to move it to the background. This comes in handy for long running tasks. Here’s how to do it:
First, pause the process in the foreground by pressing Ctrl+Z. This will stop (pause) the job and display a job ID which can be used to reference it in the shell.
$ command ^Z
Next, to continue the job execution in the background, we’ll use the bg command. This command continues the execution of the job that was stopped. Utilize the job ID to specify the process to be continued in the background.
$ bg %jobID
Listing Background Jobs
To see all your running background jobs, you can use the jobs command. This command will list all the jobs along with their statuses (running, stopped, etc.) and job IDs.
$ jobs
Conclusion
Understanding how to run processes in the background can be a vital skill when working with Linux. It allows for greater flexibility and efficiency when dealing with long running tasks. The &, Ctrl+Z, bg, and jobs commands are your allies in this journey!