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[Intro Music]

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We have just successfully created

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a new executable script called

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script.sh. And we have successfully

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executed it using the absolute or

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relative path to location of this

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script. Here are three different

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examples for execution of this

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script. But we are not able to

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access it like this. And if you

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want to do so you need to modify

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PATH variable. But first, let's

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create a new subfolder in the home

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directory for this user, 'bogdan'

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user. And inside of it, we will

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place this script file and

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afterwards we will add path to

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this 'bin' folder, to this PATH

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variable. Let's do that. Let's

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first create a new folder called

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'bin' here in home directory for this

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user. And here I see this folder.

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And now let's move this script.sh

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file into this 'bin' folder. For that

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I'll use command 'mv', and move

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'script.sh' to 'bin/script.sh'. Like

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so. And now if I list the contents

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of the 'bin' folder, I'll see script.sh

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file here inside. Let's 'cd' to

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'bin', and here type 'pwd', print

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working directory. And I see the full

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path to 'bin' folder. And now I

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need to take this path, and

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concatenate it to this PATH

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variable. For that you need to do

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following. Let's first copy

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this section; and next type following

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command, 'export PATH =

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$PATH', next ':', and

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let's now paste copied path to

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'bin' folder. What this command

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will do? It will take existing PATH

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variable and concatenate to it this

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section. Please don't forget to add

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here ':'. And afterwards, this

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resulting path will be exported

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into PATH variable. And technically

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we will rewrite existing PATH

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variable. Let's try to press Enter

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and see what will happen. Let's use

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'echo', and type now PATH variable.

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And now I see that this section was

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concatenated to previous PATH

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variable. And now I am able to

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execute that script that is located

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inside of the 'bin' folder here in

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home user directory for 'bogdan'

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user anywhere I want. Let's

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try to do that for example, here in

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'bin' folder type simply 'script.sh'

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without any prefixes, without

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any path, like so. Let's press Enter,

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and I see result. Script was

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executed successfully. 'Hello from

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the custom script'. I could 'cd' for

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example to root directory like so,

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and enter the same command 'script.sh',

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and the result will be the same.

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And the reason for that is that now

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this script is located in the PATH,

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here. And I'm able to access it

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anywhere I want. And of course, if

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you want to, you could even remove

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this extension and name the

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script without any extension at all.

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For example, let's rename it to

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let's say, 'my-script' without

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extension. Let's use 'mv' command;

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and here I need to use absolute or

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relative path to this script file,

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and let's use the relative path,

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home directory, here will be '/bin/

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script.sh', and let's rename it to

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'/bin', and here will be simply

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'my-script' without any extensions, like

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so, Enter. And now let's try to

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execute this my-script. Simply type

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'my-script', and the result is the

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same. And if I list the contents of

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the 'bin' folder like so. Let me do

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that. Let's actually add the '-l'

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option. I'll again see that this

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file is executable script, it is in

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green color. And here I see

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executable permissions for a

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specific user, for owner of this

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file. That's how you could pretty

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fast and easily allow execution of

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any executable script from anywhere

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by adding a path where this script

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is located to PATH variable like we

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did here. Great. That's all for

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this lecture. And this is all actually

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about executable scripts and

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permissions. I will not show you how to

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create more complicated scripts.

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And if you want, you could do so.

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Actually executable script is

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simply a set of shell commands,

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nothing else. You are able to

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perform any actions you like. You

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could create variables, you could

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perform any other actions like list

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files, grep output of some

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commands, and so on. Script is

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simply a set of commands that are

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executed one by one. All right,

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that's all for this subsection. And

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next let's talk about networking in

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Linux systems. I'll see you next. Bye-Bye.

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[no audio]