Minitalk

A messaging project from 42 School based on inter-process communication using signals.

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✨ Overview

Minitalk is an individual project at 42 School that challenges students to implement a simple yet robust communication system between processes using UNIX signals. In this project, a server process waits for incoming messages sent by a client process using SIGUSR1 and SIGUSR2 signals. The goal is to reliably transmit complete messages from the client to the server, handling data conversion and synchronization without using standard inter-process communication methods.

For the bonus part, I extended the project capabilities to handle more complex scenarios such as:

• Enhanced communication protocol: Allowing for larger and multibyte messages.
• Reliable transmission: Implementations to confirm message receipt and handle potential data loss.
• Improved synchronization: Managing the signal flow efficiently even with overlapping transmissions.

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📑 Key Features

• Signal-Based Communication: Uses UNIX signals (SIGUSR1 and SIGUSR2) to transmit data bit by bit.
• Server-Client Architecture:
  • Server: Continuously listens for incoming signals and reconstructs messages.
  • Client: Converts the message into binary format and sends it to the server.
• Bonus Implementations:
  • Support for extended messaging, ensuring that the entire message is reliably transmitted.
  • Implemented acknowledgement signals for improved synchronization between client and server.
• Error Handling: Robust error handling to manage unexpected signals and invalid inputs.

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🛠️ Technologies Used

• C — Core programming language.
• Makefile — Build automation tool.
• UNIX Signals — For inter-process communication.

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🚀 How to Build and Run

Clone the repository and use the following commands in your terminal:

# Compile the project
make all

# Compile the bonus
make bonus

# Remove object files
make clean

# Remove object files and executable
make fclean

# Clean and recompile
make re

Start the server first, which will display its PID, ready to receive messages:

./server
How to Run the Client

In another terminal, run the client with the server PID and the message as arguments:

./client <SERVER_PID> "Your message here"

Example:

./client 12345 "Hello, 42 School!"

🧪 Testing

The implementation was thoroughly tested using multiple scenarios, including:

• Sending short and long messages.
• Handling multibyte characters.
• Simulating rapid consecutive messages to validate synchronization.
• Bonus: Stress tests for ensuring reliable transmission under heavy loads.

Additional custom scripts and tools were developed to simulate edge cases and verify the successful receipt of messages by the server.

📸 Visual Example

✅ Results

Here’s my score for the Minitalk project:

📬 Contact

Feel free to reach out or contribute to this project on GitHub!