Navigating a file system

Open your terminal or git BASH (if you are using a Windows machine).

Note: ensure you are using git BASH and not the Windows command prompt, some of these commands will differ and we’re aiming for consistent ways of working across many operating systems.

git Bash

As mentioned in the intro to unix and gitbash, git BASH is a BASH emulator, we use this to interact with the Windows OS using a UNIX-like shell with Bash commands.

Commands and flags

You can use commands to interact with the file system, for example to change directory, copy files and many other useful tasks.

When using a command they often have optional parameters called flags. These flags pass additional context and information, one common example is --help which provides information on the application you’re using.

Common shell commands:

Where am I?

Find out where you are using:

pwd

The result returned tells me I’m in the directory /Users/adamdewberry

List files and folders

List directory contents.
Useful flags:

• -l list view
• -a show hidden (dot) files and folders

Invocation:

ls -al

Make a new directory

Invocation:

mkdir data-engineering-101

Change directory

Invocation:

cd data-engineering-101

To go back a level in your directory tree:

cd ..

Two levels

cd ../..

Printing to the terminal

Invocation:

echo "Print a string of text to the terminal"

Sending shell output to a file

In other words, creating a file and inserting the output from your command.

Invocation:

echo "Print a string of text to the terminal" >> file.txt

Remove files or directories

To delete a file or directory use the remove command.

Invocation:

rm file.txt

To remove a directory and its contents you will need the flag -r which stands for recursive, to remove the files recursively (the directory and everything in it):

mkdir dir-name/
rm -r dir-name/