Introduction to GitHub Codespaces¶

A Complete C Development Workflow¶

view slides online

Creating a Repository & Initializing a Codespace¶

• GitHub Repository (a.k.a. repo): The source of truth for your code.

  • This is where your code lives online.
  • We’ll discuss local development later, but for now we’ll stick to online coding.

• Codespace: A cloud-hosted virtual machine (VM) attached to the repo.

  • This is where we’ll be writing, compiling, running, and debugging code.

1. Create a new repository on GitHub.
2. Navigate to the Code button.
3. Select the Codespaces tab.
4. Click New Codespace.

⚡ The Environment: VS Code opens in your browser with a cloud-attached container.

Installing the C/C++ Extension¶

• Default Environment: Codespaces come with Node.js and basic editing by default.
  • Do this look like a web dev class???
• Missing Features: No IntelliSense, debugging, or C-specific tooling by default.
• Solution: Install the Microsoft C/C++ Extension.

1. Open the Extensions panel (Ctrl+X, E).
2. Search: C/C++ Extension Pack.
3. Click Install on C/C++ Extension Pack

Why? This adds syntax highlighting, error detection, and debugging support to your editor.

Disabling Copilot Autocompletion¶

• Default Behavior: GitHub Copilot suggests code inline automatically.
• Requirement: In structured tutorials, we want to see the code we write.

AI suggestions can create confusion, especially during the early stages of learning.

How to Disable¶

 1. Open Settings (Ctrl+,).
 2. Search for Disable AI Features
 3. Check the option.

Impact: Prevents code from being auto-inserted, allowing you to learn the syntax manually.

Writing a Hello World C Program¶

File: hello.c

&emsp;#include <stdio.h>  
  
&emsp;int main() {  
&emsp;&emsp;&emsp;&emsp;&emsp;printf("Hello, Codespace!\n");  
&emsp;&emsp;&emsp;&emsp;&emsp;return 0;  
&emsp;}  

Compile & Run:
 bash  gcc hello.c -o hello  ./hello  

Goal: Confirm the environment is compiling and executing C binaries correctly.

Git Basics & Repo Relations¶

The VM Nature of Codespaces

The Workflow:¶

1. Local Repo vs. Remote:
     - Codespace: The ephemeral VM running on GitHub’s servers.
     - GitHub Repo: The permanent storage of your code.
2. Synchronization:
     - Changes in the Codespace do not auto-push to GitHub.
     - You must manually manage files.

Commands:¶

git status            # Check uncommitted changes  
git add .             # Stage all files  
git commit -m "hello world" # Save state  
git push              # Push to GitHub  

¶

Key Concept:¶

• VM Nature: If you close the Codespace without pushing, changes might exist only in the container memory.
• Persistence: You must git push to save your work to the permanent repository.

Tip: The code you see in the Repo (GitHub.com) might lag behind the code you are editing in the Codespace until you commit and push.

Summary¶

1. Setup: Open a Codespace from a Repository.
2. Tooling: Install C/C++ Extension.
3. Focus: Disable AI auto-completion.
4. Code: Write and run C programs.
5. Version: Commit and push changes to GitHub.

Final Thought: Codespaces are powerful, but you must treat them as ephemeral containers requiring explicit version control management.