Session 2: Basics of the Command Line

Track, organize and share your work: An introduction to Git for research

Course at General Psychology Lab at the University of Hamburg

Slides | Source

License: CC BY 4.0 DOI

Dr. Lennart Wittkuhn
lennart.wittkuhn@tutanota.com

10:00

1 Logistics & Admin

Schedule

No Time Title Contents Reading Survey/Quiz
1 9:30 - 10:00 Welcome & Introduction to Version Control Logistics and course admin
Results of course survey
Introduction to version control
Introduction to Git		 Introduction to Version Control Course survey
2 10:00 - 10:45 Basics of the Command Line File systems and navigation
Benefits of the command line
Basic command line commands		 Command Line Command Line Quiz
3 10:45 - 11:30 Setup & First steps with Git Configuration and setup of Git
Initializing a Git repository
Fundamental Git commands
Tracking changes wih Git		 Setup, First steps with Git, Git Essentials Git Basics Quiz
4 11:30 - 12:15 Branches, Merging Merge Conflicts Understanding branches in Git
Creating and switching between branches
Merging branches
Resolving merge conflicts		 Branches Git Branches Quiz
5 12:30 - 13:30 Lunch Break Enjoy your lunch!
6 13:30 - 14:15 Integration with GitHub / GitLab Introduction to remote repositories
Managing repositories on GitHub / GitLab
Pushing and pulling changes
Cloning a remote repository		 Remotes Intro GitHub Quiz
7 14:15 - 15:00 Collaboration on GitHub / GitLab Forking
Collaboration with GitHub Flow
Pull / Merge Requests
Issues
Project Management		 GitHub Advanced, GitHub Issues GitHub Quiz
8 15:00 - 15:30 Summary & Outlook Summary of course contents
Outlook to more Git topics
Discussing open questions

Course exercise: Building an online recipes book

https://lennartwittkuhn.com/recipes

2 Basics of the Command Line

This session: Basics of the Command Line

Source: Wikimedia Commons (free license)

Learning objectives

đź’ˇ You can navigate directories using the command line.
đź’ˇ You can use shortcuts like the tilde or dots to navigate your file system.
đź’ˇ You can explain the difference between absolute and relative paths.
đź’ˇ You can use arguments and flags to modify command-line commands.
đź’ˇ You understand the concept of wild cards (*) and can use it for system navigation.

Reading

https://lennartwittkuhn.com/version-control-book/chapters/command-line.html

Cheatsheet

Command Description
pwd Displays the path of the current working directory
cd <PATH> Changes the current working directory to <PATH>
cd ~ Changes the current working directory to the user’s home directory
cd .. Moves up one folder
cd ../.. Moves up two folders
clear Clears the contents of your command line window
ls Lists files and folders in the current working directory
ls <PATH> Lists files and folders in <PATH>
ls -a Lists all files (including hidden files) in the current working directory
ls -alh Lists all files in a long format that is easy to read for humans
[Command] --help Displays all possible flags for a specific command (on Windows)
man [Command] Displays all possible flags for a specific command (on macOS)
mkdir <FOLDER> Creates a new folder called <FOLDER>
mkdir <FOLDER1> <FOLDER2> Creates two separate folders called <FOLDER1> and <FOLDER2>
touch <FILE> Creates a new empty file called <FILE>
open <FILE> Opens the file called <FILE> (on macOS)
start <FILE> Opens the file called <FILE> (on Windows)
echo "example text" >> file.txt Writes “example text” into file.txt
cat <FILE> Displays the content of <FILE>
mv FILE.txt <FOLDER> Move FILE.txt into <FOLDER>
mv <FOLDER_OLD> <FOLDER_NEW> Renames <FOLDER_OLD> to <FOLDER_NEW>
ls -alh *.csv Uses a wildcard to list all .csv files in the current working directory
rm -r <FOLDER> Removes the folder <FOLDER>
history Display the command history of the current terminal session
history > history.txt Saves the entire command history to a file named history.txt (overwrites existing content in history.txt)
history >> history.txt Adds the entire command history to the end of the file named history.txt
tree Displays a graphical representation of the directory structure
wget <URL> Downloads a file from the specified to the current directory

Tasks

In this session, you will work on the following tasks:

  1. Reading: Read the chapter “Command Line” in the Version Control Book.
  2. Implementation: Try out the commands in the chapter.
  3. Exercises: Work on the exercises for the recipes project.
  4. Quiz: Test your knowledge with the quiz.

As always:

  1. Try out the commands of this session and play around with them.
  2. Check whether you have achieved the learning objectives.
  3. Ask questions!
  4. Let’s git started!

recipes project

At the end of this session, you should have accomplished the following:

  1. You used the command line to create a folder on your computer called recipes.
  2. You used the command line to create a file called recipes.txt inside the recipes folder.

Please keep the recipes folder! We will continue to use it in the following sessions.

Exercises

Identify a folder on your computer where you (want to) keep course-related files. If you don’t have one, choose a suitable location in your file system.

  1. Navigate into the chosen location.
  2. Use the command line to display the path of your chosen folder.

Create files and folders

  1. Create a new subfolder and name it recipes.
  2. Navigate into the recipes subfolder.
  3. Create a new file and name it recipes.txt.
  4. Confirm that the files was created by listing the contents of the folder.

Solutions

Code
cd /path/to/your/chosen/directory # <1>
  1. Navigate into the chosen location. Replace /path/to/your/chosen/directory with a path on your computer. A good location might be within your /Documents folder or a dedicated /Projects or /University folder. This can help to easily find course-related files on your computer.

Create files and folders

Code
#!/bin/bash

pwd # <2>
mkdir recipes # <3>
cd recipes # <4>
touch recipes.txt # <5>
ls # <6>
  1. Use pwd to display the path of your chosen folder.
  2. Use mkdir to create a new subfolder and name it recipes, within your chosen folder.
  3. Use cd recipes to navigate into the recipes subfolder.
  4. Use touch recipes.txt to create a new file and name it recipes.txt.
  5. Use ls to confirm that the files was created by listing the contents of the folder.

Version Control Course