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- This lesson is about
interactive shell jobs.

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When a user runs a command,

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this command is started
as a foreground job.

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That means that you cannot
do anything else anymore;

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Your console is occupied.

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One thing that might be useful is to

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move a running process to the background.

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You can do that by using Control + Z,

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followed by the bg command.

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To start a new process in the background

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use Command followed by an &

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and you'll never see it in the foreground.

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It immediately goes to the background.

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To get an overview of all the jobs

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that are currently
running in the background,

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you can use the jobs command.

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And the fg command is what you can use

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to move a current job back-

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And the fg command is what you use

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to move a current background
job back to the foreground.

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Let me show you.

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So let me start a command
that's doing nothing.

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dd if=/dev/zero of=/dev/null

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It's basically copying nothing to nowhere.

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If I press enter, it occupies
my console, as you can see.

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So there's nothing else
that I can do anymore.

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So I need Control + Z
to temporarily stop it.

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If you use the jobs
command at this moment,

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we can see that the job
is temporarily stopped.

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And that's because it's
waiting for me to type bg

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to continue running it in the background.

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Now I can immediately run
my jobs in the background

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by putting an & behind it,
as you can see right here.

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And let's do that one more time

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so that we have a couple of jobs

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and here we have the jobs command

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and the jobs command
is showing all of them.

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Now, if I want to move one of
these jobs to the foreground,

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I can use fg for foreground
followed by job number.

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And now job number two is
running on the foreground.

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And if I want to stop it,

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then I'm using the generic Linux solution

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to stop running things: Control + C

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There, you can see that
the command outputs

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that it has copied 12 gigabyte
of nothing to nowhere.

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Very interesting.

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And the jobs command is showing

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the other job's still running.

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Now, if you use fg,

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then we move it to the foreground

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and we can use Control + C to stop it.

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And one more time, fg and Control + C.

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And now they're all gone,

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which can be verified
with the jobs command.

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Now this job management
is convenient for users

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because users can manage their own jobs.

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Administrators can manage everybody's jobs

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and that is what we are
going to talk about next.