##Opening
"In the beginning was... the command prompt"
GUI stands for:
- Graphical
- User
- Interface
Before we had a Graphical User interface (GUI) all we had on a computer was displayed using a the CLI.
CLI stands for:
- Command
- Line
- Interface
We going to develop a lot in the command line, we will use it every day on this course. It will greatly speed up our development process and it will make us feel like hackers!
The shell is a user interface for access to an operating system's services. It is just a program that accepts commands as text input and converts them to appropriate operating system functions.
It is the doorway into our computer's underbelly...
- Reference to Matrix
- Type like a hacker
WDI London uses Z Shell, (ZSH) which is a shell designed for interactive use.
First, we need to launch the command prompt. We do this by using spotlight:
cmd+space + "terminal"
and typing terminal followed by enter.
The program is located in
/Applications/Utilities/Terminal.app
(Open two tabs)
To exit the command prompt, you can use exit or cmd+d.
You can also quit and force quit the application.
You might not need to completely shut down the console but you might want to terminate a running process because it might be in a loop.
cd ~/
We're "looking into" the User directory at this point...
Use the TAB and arrow keys in the command line to increase your speed while navigating the command line.
cd + tab + arrow keys
If you don't press enter, just press delete to remove characters...
Pressing UP will also get the last command written.
cd <directory name>
cd means Change Directory. This will move us into our specified directory. We can normally leave out cd in zsh.
cd
Without a specified directory this will take us to our home directory, the same as cd ~
Using zsh you don't need to use cd. It is a good habit to get into though.
~
The tilda character will take you back to your User directory.
You will need a cd for navigating using one dot.
.
# Will need to do cd .
Is a pointer to the current directory, however using zsh you can't do just . or you will get an error .: not enough arguments
..
Is a pointer to the parent directory
pwd
Present working directory
ls
List of items in current directory
ls -a
Will list all items in the current directory including hidden files.
ls -l
Will give you a long list of item in the current directory including permissions, size and last modified date.
history
Will list your entire commands history (use !line_number to retrieve a specific command)
grep
# history | grep <search item>
history | grep cd
Global regular expression parser - can be used with history to search.
Navigate to Desktop
mkdir <directory name>
Will create the specified directory.
df -h
Display free disk space
mkdir <nameofdirectory>
Makes a new directory.
cd <nameofdirectory>
touch <filename>
Will create the specified file.
mv <filename> <filename2>
Is used for both moving files and renaming them.
cp <file to be copied> <name to copy it to>
Will copy first file to the name of the second file if specified
and renaming them, e.g
rm <filename>
Removes the specified file
rm -rf <directory name>
Removes the specified directory (Use with caution, make sure you are in the right place. "-rf" stands for recursive forced, and you can imagine how bad the results could be if you did that in your home folder!)
##We Do:
####Directions to students:
Navigate to the desktop.
mkdir films
to make a directory
cd films
to go into that directory
ls
to see where you are (directory is empty, nothing there)
touch casablanca
to make a file
subl casablanca
to open that file in sublime. Add some text and then close Sublime.
touch jaws titanic twilight
to make more movies!
mv jaws jaws2
to rename a file
subl .
to open the whole directory. Edit some files and then close Sublime, make sure everything is saved.
rm casablanca jaws
to remove a couple movies.
You can also increase speed by using aliases which need to be added to the '.zshrc' file.
# Add in ~/.zshrc
##You Do: Keyboard shortcuts
Here are a list of keyboard shortcuts. You don't have to use them but if you remember them you will spend less time navigating the terminal and more time writing code.
| Keypress | Action |
|---|---|
| Ctrl + A | Go to the beginning of the line you are currently typing on |
| Ctrl + E | Go to the end of the line you are currently typing on |
| Ctrl + L | Clears the Screen, similar to the clear command |
| Ctrl + U | Clears the line before the cursor position. If you are at the end of the line, clears the entire line. |
| Ctrl + H | Same as backspace |
| Ctrl + R | Let’s you search through previously used commands |
| Ctrl + C | Kill whatever you are running |
| Ctrl + D | Exit the current shell |
| Ctrl + Z | Puts whatever you are running into a suspended background process. fg restores it. |
| Ctrl + W | Delete the word before the cursor |
| Ctrl + K | Clear the line after the cursor |
| Ctrl + T | Swap the last two characters before the cursor |
| Tab | Auto-complete files and folder names |