Minitalk

Description

The Minitalk project involves creating a simple communication protocol between two programs using UNIX signals. It consists of two components:

• a server (receiver)
• and a client (sender). The concept of using UNIX signals for inter-process communication is inspired by classic low-level systems programming tasks.

To help me understand better bitwise operations and their potential, I wrote an additional library LIBSORT whose functions I used to solve this task.

Technologies Used:

• C
• UNIX Signals

Table of Contents

• Installation
• Usage
• Features
• Contributing
• Acknowledgments

Installation

To test this project locally:

1. Clone this repository:

   git clone https://github.com/pepper/minitalk.git

2. Navigate into the project directory:

   cd Minitalk

3. Compile the server and client by running:

   make
   

Usage

1. Server:

   • Open the first terminal.
   • Run the ./server program. Its PID (SERVER_PID) will be displayed.
   • The server will display the received message in the terminal once it's fully transmitted.

2. Client:

   • Open the second terminal.
   • Run the ./client <SERVER_PID> <MESSAGE>.
   • The message (any string) is sent to the server as a sequence of signals (binary data).

Example:

# Server Terminal
./server
Process ID (PID): 12345

# Client Terminal
./client 12345 "Hello 42 Nice"

Features

The Minitalk project achieves communication employing the following mechanisms and protocols. The server listens for signals (SIGUSR1 and SIGUSR2) using sigaction. Each signal corresponds to a binary bit (SIGUSR1 for 0, SIGUSR2 for 1). Characters are transmitted one at a time as binary data. Once 8 bits (1 byte) have been received, the binary string is converted into the corresponding character. To prevent buffer overflow, the client waits for a signal from the server (acknowledging the reception of the previous bit) before sending the next one. A small delay (usleep) is used between signal transmissions to avoid overwhelming the server.

Contributing

This project is pretty straightforward, but if you have suggestions for improvements, bug fixes, or interesting features, feel free to contribute.

How to Contribute:

• Fork the repository.
• Create a new branch (git checkout -b feature-branch).
• Make your changes and commit them (git commit -am 'Add new feature').
• Push to your branch (git push origin feature-branch).
• Open a pull request.

Acknowledgments

Thanks to the 42 Nice community!