Shell Shortcuts

These are some common tips and tricks for when you’re working in at the command line or in the shell.

Key Syntax

We frequently have to use key combinations at the terminal. Some common notations are:

• Caret (^) syntax
  • ^C means “hold down Control and C at the same time”
  • ^X means “hold down Control and X at the same time”
  • etc.
• Angle brace syntax
  • <C-C> “hold down Control and C at the same time”
  • <C-X> “hold down Cotnrol and X at the same time”

Also, <CR> is not a typo for <C-R>. Instead, <CR> stands for “carriage return” and basically just means “ENTER”.

Tab Completion

Typing things out is very time consuming and error prone. The shell has a feature called tab completion which lets you press “TAB” to automatically complete the names of files when you’re running shell commands.

cd Shortcuts

There are a few fancy shortcuts for cd:

• cd ..
  • Go to the parent directory
• cd -
  • Go to whichever directory we were in before we cd‘d here
• cd (no arguments)
  • Go to my home folder

Command History

Bash keeps track of all the commands you run, and you can use this to your advantage.

• history
  • This command will show you a list of all the commands you’ve run.
• !!
  • This will expand to the last thing you ran.
  • For example, to re-run a command, but to run it as sudo, you can run sudo !!

Quitting

There are multiple ways to try quitting things.

• ^C
  • This is used to interrupt the current process. Normally, this will kill the program. However, programs can choose to ignore this request.
• ^D
  • Sends the “EOF” (end of file) character, signaling that there is no more input. This usually causes a shell to exit.
• Press q
  • Inside some programs, like less or man, you can press q to quit.
• Press :q
  • This one is specific to Vim.

Keyboard Layout

When you work at the command line often, you end up pressing Control and Escape frequently. Also, chances are that you don’t use Caps Lock that often. As a result, you may want to change your laptop settings to send either Control or Escape instead of Caps Lock when you press the Caps Lock key.