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[Intro Music]

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All right, now let me demonstrate

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you how you could get the list of

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all running processes. For that you

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could use command called 'ps'. If you

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enter this command, you'll see

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currently running processes for

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this particular session. And at the

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moment, I am inside of the Ubuntu

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container. And I'm inside of the

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bash process, I'm connected to

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standard in of this process. I will

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talk about what is standard in,

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standard out in one of the next

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lectures. Now, you understand that

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I am in bash process; and this

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process is listed here with

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Process ID 1, here it is; and

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here is command that was used for

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start of corresponding process.

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That means that when you enter any

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command, Linux Kernel basically

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starts specific process. And as you

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may have noticed, here is another

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process, 'ps'; and this process

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appears here, because I have just

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entered command 'ps' that has

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started corresponding 'ps' process.

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But I have got this output from

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this 'ps' process. And basically,

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this process did its job, and it is

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not needed anymore. That's why this

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process was terminated, was stopped.

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And if you enter 'ps' once again,

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you'll see 'ps' process once again on

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the list, but this will be brand

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new process. You may notice here

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difference between those processes

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ID, here and here. Alright, you are

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also able to get the list of

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different options that you are able

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to use with 'ps' command using

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following, ''ps --help'

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command; and actually, if you want

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to get help for 'ps' process, you

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need to add also here, which

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section of help you want to see.

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And if you enter here, 'all' or

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simply 'a', like this, you'll get all

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available options. And if you'll

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scroll a bit up, you'll find the

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most commonly used options here in

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this first section. For example,

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with '-A' or '-e'

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you are able to get list of all

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processes. By default, you'll see

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all the processes running by

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current user. And if I'll enter

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this option now, 'ps -e', I'll see

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same two processes 'bash' and 'ps'; and

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'bash' has Process ID 1, and 'ps' has

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in my case Process ID 5153. And the

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reason for that is that I'm

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actually running a small Ubuntu

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container, and there are no other

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users logged into this container,

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there is no graphical user

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interface for this Ubuntu

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container, that's why there are

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only two processes in total. But if

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I switch to Ubuntu computer and

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list all processes here, 'ps -e',

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I will see a long list of

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different processes, because here

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you see now full featured

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computer with Ubuntu operating

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system. It has this graphical user

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interface, it has different

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applications running, that's why it

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has much much more processes. Here

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is complete list. But if I enter

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'ps' without any additional options,

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I'll see similar output to this

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picture. I see only two processes,

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'bash' and 'ps'. And that's what I

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have told you, with 'ps' command

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without any additional options

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you'll see only processes

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started by a particular user. And

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this user in this case is Bogdan.

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Alright, that's all for this

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introduction lecture, and next

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let me demonstrate to you how to start

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additional processes, and how to

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kill processes. I'll see you next. Bye-Bye.

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[no audio]