Thread: unix terminal tutorial

Welcome
Hi, and welcome to my little tut on the linux terminal. I'm not even close to being a pro, so I apologize in advance if I mess up. I'm writing this tutorial with Ubuntu 10.4 Lucid Lynx.


Commands sent to the console will have a

quotation box

Whatever the terminal shows/spits out will be in italics.


I'm not sure why, but most *nix beginners tend to stay away from the terminal (I did, anyway)! But hey, you'll learn that its not that bad after all.

Getting Started
Ok. To get started, goto: Applications -->Accessories-->Terminal.


Now, a terminal will pop up. It's easy to get intimidated, but don't get scared—it's easy. You should see a blinking cursor. Before that cursor, you probably see:



yourName@ubuntu:~$

Our first command
Let's try something simple. Type

pwd

Good job! You just completed your first command in the console! (it wasn't that bad, right?)


After typing “pwd”, you'll see that the terminal says something. It should say:
/home/yourName


This represents where you are. When you navigate graphically, you click, right? You double click on the folders that you wanna go into. Similarly, you move around in the terminal by issuing commands to the console. Let's try another.

ls and hidden files
Type:

ls

Your terminal should give you (most) of the folders/files that it can see in /home/yourName. For me, it has stuff like:
Desktop Downloads Music Programming Videos Documents
…etc


However, we're not seeing the whole picture. Some files are hidden! To see those, type this:

ls -a

Whoaa! My whole screen filled up with more items! You should see stuff like .compiz, .evolution, .gconf, .mozilla, .bash_history, .bashrc
…..etc

Text Editing!
Let's edit .bashrc. There are two ways to play around with this file. Let's first try vi/vim. Type

vim .bashrc

(note: if this doesn't work, type vi .bashrc)


Now, you'll see some REALLY random stuff! All you are seeing is some code in bash. The weird thing about vi/vim is that you can't edit right off the bat (wouldn't recommend anyway, lol). Try it, if you don't believe me! Type f, or g, or h. Nothing happens! This is because you are in command mode. To edit stuff, you have to be in insert mode. Type “i” to enter insert mode. Now you can edit stuff. Anyway, don't be discouraged if vim feels weird. I'm learning it too. To exit insert mode, press Escape. Ok. We are going to quit without saving changes. To do this, type

:q!

After you type the semicolon, you should see what you type in the bottom left corner, like this:

Press enter. This will quit the file you were editing without saving any changes you made. To save changes, you would type

:wq

If vim intimidated you, don't worry! There's nano too. Try this:

nano .bashrc

You should be more comfortable. You can move around and edit from the beginning. It's a lightweight but powerful text editor. To quit, simply press Control-X. If it asks if it wants to save changes, just hit N for “no.” See? Nano aint that bad, right?


Shortcuts and Autocompletion
Let's play around some more with the terminal. Type

ls

You know this command. It shows the files/directories you can access. Now, we will change directories with the cd command. Type

cd Downloads

You'll move into the Downloads folder. Check if you've really gone into it by typing

ls

again. Does it look different? Nice! You've successfully changed directories! Let's go back to the previous folder. We can do this the fast way or the slow way. Let's do it the slow way first. Type

cd /home/yourName

This'll transport you back to where you where. Ok let's go back to Downloads. Type

cd Downloads.

Ok. Now, type

cd ..

(two dots). And... you're back to your previous directory. Pretty cool huh? There's also a quicker way to go to the Downloads folder too. Ok. Type this:

mkdir gooper_hash.99_pzxxs

What this command does is create a directory with the name that we provided. It's pretty disgusting, huh? Sometimes, you'll get files that are just plain annoying to type. So, there's something called autocomplete. Type

ls

to make sure that the gooper directory exists. Ok. Now, type "goop" (w/o quotes) then press Tab. Then boom! The terminal should do all the work for you. Awesome, right? Ok, so, to go to Downloads (make sure that you are at /home/yourName), type

cd Dow

then press Tab. It should autocomplete.




Wrapping up with something fun :laugh:
The terminal is fun, no? Ok. Let's wrap up with something fun! Let's say that you're torrenting (or whatever) and you want your computer to shut off at 3:30 in the morning to save electricity after Dling/seeding for a couple hours. You can do that in the terminal easily! Type

sudo shutdown -P timeInMinutes

Replace "timeInMinutes" to how many minutes you want your machine to wait until shutdown. So, if its 12:00AM right now and I want a shutdown at 2:30AM, I would type

sudo shutdown -P 150

The "-P" flag will tell the computer to power off. If you typed

sudo shutdown -r 5

your computer will restart in 5 minutes. The terminal will then prompt for your pass. Simply type it in. I really hope I did the math right. Please correct me if I'm wrong (the 150 minute one).

Fin
And that's it! You have successfully mastered the basics of the terminal! Congrats!
:laugh:

This should help beginners like me embrace the power of CLI. I was a bit uncomfortable with vim. So I used nano/gedit. I will try to familiarize it though. I am glad I moved my torrenting to CLI.

Nicely explained :)
One remark though, it's not unix terminal like stated in topic name, and commands differ of course, not too much but they do :)
Unix is completely different osys .