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[Intro music]

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Hello everyone. In this lesson we will cover the

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Linux file editor. An editor is a program which

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enables you to create and manipulate data or text

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in a Linux file. There are several standard text

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editors available on most Linux systems. You could

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use vi, ed, ex, emacs, pico, vim, which is,

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vim is the advanced version of vi. In our

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lesson, we will focus on vi. Why? Because vi is

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available in almost every Linux distribution,

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regardless of which Linux system you log in.

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Whether it's Ubuntu, SUSE, Red Hat, CentOS, you're

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gonna find vi everywhere. Plus, it's very easy to

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learn. The vi editor actually supplies commands

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for inserting or deleting text, replacing text,

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moving around the file, finding substitute

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strings, and cutting and pasting text inside. So

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that's what vi does when you have to write to a

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file. The most common keys are i which should

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insert, escape, replace for r, d for delete,

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and quit without saving, and quit write with save.

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So let's look at our Linux machine. And at this

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time, we will log into our Linux machine, the

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Linux virtual machine through our PuTTY session.

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[No audio]

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Okay, let's cd, whoami, and which directory we are in.

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[No audio]

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In this directory, I want you to create

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your first file, so call it vi, which is a

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command, space myfirsteditor,

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or just say myfirstfile, how's that? Much easier, hit enter.

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Now, when you hit enter, you are still in command

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mode, you are not in insert mode. So there are two

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different modes once you are in the vi. This first

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mode is to when you run the command, second mode is

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when you're inside of the vi and you start typing it.

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If you want to get out of that typing mode, you

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have to hit escape. So now let's start, let's say

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if I wanted to type into this file, you hit i for

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insert, lowercase i. As soon as you hit it, you will

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see at the bottom, it says INSERT. It means we are

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in insert mode. Now our regular Linux commands

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won't work because we are in insert mode.

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So let me type something like Hello World.

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This is my first lesson to learn vi. And you could

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hit enter again, I am so excited about it. So it's

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just simple as if you're typing a word document.

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Now if you wanted to exit out of it, if you want

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to save this file, all you have to do is hit

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escape right here. And once you hit escape, you'll

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see the insert mode is gone. Now how do you save

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this file? You could do through two different

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ways. One, you hit shift zz,

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the zz twice, and it

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will save the file. Let's see, if you do cat again,

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and do myfirstfile, you'll see it's there.

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Another way to save a file, let's go back in the

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file, myfirstfile, and let's say you want to type

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something, hit insert again, and then hi space.

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And now you want to exit out and save, hit escape,

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and this time instead of shift zz, you type shift,

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colon, write, quit, and exclamation point, which is

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also referred to as bang, you hit enter. How do you

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verify? You read the file myfirstfile, and there

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you go, the file is there. So these are the

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two modes, is once you get out and once you get in.

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Now I want you to go back into your file and hit

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vi and myfirstfile,

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and I want you to replace

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[No audio]

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hi, no I want you to delete hi and leave that as is.

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Now how do you go move around inside of a file

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when you are already in your editor. You could use

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up, bottom, left, right keys on your keyboard to move around.

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[No audio]

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But remember, you cannot use these

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keys if you are in insert mode. So let's say if

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you hit i, and you now in insert mode, and now

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you do a left, right key, it can work, but most

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likely it will break your commands. So it's better

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you hit escape, and go back, and then you do d on your keyboard, d.

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[No audio]

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This will delete the entire line.

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I wanted to delete only the word hi. So how do I

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get back my last line that I deleted. So you hit

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u, just simple u, and it brings back your last

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line. Now, if you wanted to remove the hi, just

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type x, once, which will remove one character, type

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x again, which will remove another character, now

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you have a space, hit x again. Now you don't have a

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space. Now what if you want to save now, again do

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shift zz, twice, and it saves it. How do you verify

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it? You do cat myfirstfile, and it is there.

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Now let's go back in again, and let's practice the replace command.

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vi myfirstfile. I want it to

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replace, I am so excited about it.,I want it to

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replace the word excited with the word happy. So

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how do we do it? We cannot hit i right now

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because we don't want it to get into the insert

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mode. So we will use our arrow keys to go down to

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the word excited, so I could do r.

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Once I hit r, I

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could do h, it only replaced one letter. If I

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wanted to do again the second letter, you move

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your cursor to the right, hit r, and then do a, and so

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forth. But I would prefer that you do escape out

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of it. And then do x x x x x, and then you hit i,

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and then ppy. You hit escape again. so you can

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move around. You could go up, you could go down if

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you wanted to move around. Now what if you

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want to go to the end of this file, and now you

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want to create a new line right below it, before I

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am so happy about it, you hit o. This will create

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a new line for you, and also it will automatically

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put you into the insert mode. So you could type

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anything like blah blah blah. But you just

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noticed that you just type j by mistake. Now how

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do you remove j, you type x. Now remember if you're

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going to type x, it will write x instead of deleting

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it. Look, see it is typing the x. So why to delete that

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character? How do I delete that character, it is

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because you cannot delete. Why? Because you are in

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insert mode. How do I get out of insert mode? You

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hit your life saving key which is escape.

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As soon as you hit escape, you see the insert mode

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is gone. Now when you hit x x, it deletes those

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two characters that you added by mistake, it was a

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typo that you added. Same way if you want to go up,

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you could, if you want to write something right

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here, and if you type i, you notice it start

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writing right in the middle. Hellohi, see without

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giving the space. So let's do escape again. Hit x,

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move the cursor to the left, and x, okay. And now

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you have that space in the middle. Now how do I

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write by putting a space in the middle? I do a, So

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a will automatically advance to the next space. So

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Hello hi bye space world. Okay, now you're

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still in insert more, what if you want to save it?

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Before you save it again, get out of insert mode

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by hitting escape, and do shift zz. This saved

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your file, cat, myfirstfile, and it is saving

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your first file. Now what if I wanted to delete

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the line, blah blah blah, the third line. So

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I'll go back into my file vi myfirstfile, move

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your cursor down to blah blah blah, and hit d d

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twice, one, two. There you go, it removes the line

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that you added wherever you want to go. If

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you want to, oh, you removed it by mistake, no

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problem, u will bring it back. Again, you

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could save it through shift zz, or you could save

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it through colon write quite,

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and bang, you could hit enter. And that's how you

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save the file. Now let's go back into the file one

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more time. vi myfirstfile, and I want to let's

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say, I have a file, which is huge, and I wanted to

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search for a specific word in a file. Let's say I

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wanted to search for lesson, I wanted to search

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for l. So you could do search for it two ways. I

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hope you remember the command grep. And then you

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search for lesson, from where, myfirstfile. And it

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will only bring that one line that has the word

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lesson. But if you are in vi mode, you could also

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do that same search. And now you could just simply

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make sure you are not in insert mode, simply hit

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slash and type lesson, lesson, hit enter. And

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there, it will bring you to exactly the word that

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you want to change perhaps, or you are looking for it. So

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these are the few commands that we have about

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creating a file using vi. We do have many different

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commands or keys that we could use in vi. I have

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included in this lecture, I have included all those

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keys as a handout. So please

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look into those and try every single key, I really

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want you to be very familiar with this and become

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eventually become an expert. So when you're typing

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in something in your text file, you know exactly

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which key you're going to work into, or which

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exactly key you're going to use. One common

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mistake that everybody is going to make is, when

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you are in insert mode, you're probably going to

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have to get out of it, you can, your typing x, this

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and that, but you cannot. So your lifesaver is you

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do colon, no first, sorry, first is escape colon

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Q. Now this time don't write W. The W will write

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your changes the file, you don't want to make

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changes. So just to quit, colon quit, bang, hit

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enter, verify it. There you go. See now you don't

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have that garbage that you were going to write

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your file into. So this is another way you get out

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and change your file. So please practice, man also

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give you different options to use it. There's

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again, there's another editor if you like to use

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which is vim, which is an advanced version of vi or

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you could use that too, which is also available

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most of the Linux distribution, whichever you

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like, but please do practice. Practice as much as

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you can. And I will recommend that you create

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files many files in your home directories or

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within your subdirectories create your files and

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write wherever you want to. Write ABC, or write a

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story or whatever and change your text. This is

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this is going to allow you to practice vi editor.

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[No audio]