Additional Topics

Tab Completion

Hitting <TAB> autocompletes what you're typing, based on the names of the files and directories in your current directory. Hit <TAB> constantly to make yourself more productive.

Filename Wildcards

Sometimes we want to refer to a bunch of similar files, to do this we can use wildcards. Think of wildcards as placeholders for any text. The most common wildcard to use is * usually along with a file extension.

ls -la *.txt

The above command lists all files that end in .txt, but begin with anything.

History

Lastly, there are a few different commands for checking your terminal's history. What have we been up to? Use the up and down arrow keys, or the history command.

<UP ARROW>

<UP ARROW>

<DOWN ARROW>

<DOWN ARROW>

history

Environment Variables

Your current terminal session has variables called environment variables. There are really useful for storing commonly used commands and settings. Try typing env to view all of your environment variables.

You can also set your own environment variables in your shell's configuration file ~/.zshrc. Storing the variables in the configuration file will load them for every session.

If you want to create a temporary environment variable, here's an example:

export MY_SETTING='subl .'

To access the variable:

$MY_SETTING

Getting Help

For any command we discuss here, the command man, short for manual, will give a (hopefully) detailed explanation of that command. Sometimes that explanation will be too detailed for you. When you get lost in a man page and you want to understand it, start again from the beginning of of the man page and keep repeating. Hopefully you will get further into the page each time you read it.

Many third party commands also accept the --help option, but not all, but if you get stuck it can be worth a try. Most of the commands covered in this lesson overview do not support this feature. However, commands like git do!

Useful Links

• Terminal Cheat Sheet
  • You may want to start bookmarking this and other resources you find helpful
• Different Flavors of Shells
  • You can try entering these shells by typing their names
  • Example: bash opens the bash shell. Type exit to exit the shell
• Command Line Crash Course
  • A useful tutorial similar to ours, but with a few additional commands
• File Permissions
• Shell Scripts
  • We won't cover this much, but there's a whole scripting language for running programs in the shell! Try going through this sometime to become a productivity mastermind.