🐚 Minishell

Welcome to Minishell, a simplified recreation of a Linux shell! This project, developed at 42 Madrid, is designed to provide hands-on experience with process management, file descriptors, and fundamental shell functionalities.

📜 Table of Contents

• 📖 About the Project

• 💡 Problem Statement

• ⚙️ How It Works

• 🚀 Features

• 🛠 Requirements

📖 About the Project

Minishell is a project aimed at building a minimalistic shell, mimicking essential features of Bash. It provides an opportunity to delve into UNIX process management, system calls, and the intricate workings of a shell.

This project is part of the curriculum at 42 Madrid and follows strict guidelines to encourage low-level programming skills, error handling, and robust software development practices.

💡 Problem Statement

Shells are the backbone of UNIX-like operating systems, acting as an interface between users and the system. Understanding how a shell works at a fundamental level is crucial for system programming, security, and performance optimization.

Minishell aims to provide a deep understanding of:

• How processes are created and managed.

• The role of file descriptors in input/output redirection.

• Signal handling and built-in command execution.

• Implementing pipelines and environment variable management.

⚙️ How It Works

Minishell functions similarly to Bash but with a limited scope. It handles user input, parses commands, executes built-in functions, and manages processes effectively. Key elements include:

Lexing & Parsing: User input is tokenized and structured into commands.

Execution: The shell handles both built-in commands and external programs.

Process & File Descriptor Management: Redirections and pipes are implemented using system calls.

Signal Handling: Properly managing signals like Ctrl+C, Ctrl+D, and Ctrl+Z.

Environment Handling: Managing $PATH, custom variables, and command execution.

🚀 Features

• ✅ Basic command execution (like ls, echo, cat).
• ✅ Built-in commands (cd, pwd, export, unset, env, exit).
• ✅ Redirections (>, >>, <).
• ✅ Pipes (|).
• ✅ Signal handling (Ctrl+C, Ctrl+D, Ctrl+Z).
• ✅ Environment variable management.

🛠 Requirements

• 🛠️ Operating System: Linux or macOS.
• 🔧 Compiler: gcc (GCC 9+ recommended).
• 🔗 Make: Required for build automation.
• 📚 Readline library: For command history and interactive input (optional but highly recommended).
  • On Ubuntu/Debian: sudo apt-get install libreadline-dev
• 📂 libft: Auxiliary library (if allowed by the Norm and project rules; included in the libft/ folder with its own Makefile).