Minishell

Minishell is a custom Unix shell built in C as part of the 42 curriculum. It supports executing commands with arguments, pipelines, input/output redirection, environment variable handling, and built-in commands such as cd, echo, pwd, export, unset, and exit. The shell manages multiple commands connected with pipes, handles child processes using fork() and execve(), implements proper signal handling, and ensures robust error management and memory safety, providing a functional minimal shell environment.

Features

• Parsing and executing multiple commands with arguments
• Input and output redirection, including here-documents
• Built-in commands: cd, echo, pwd, export, unset, and exit
• Pipelines connecting commands with proper inter-process communication
• Signal handling for Ctrl+C, Ctrl+D, and other interrupts
• Memory-safe and robust against invalid input or command errors

Program Rules

• Only valid commands, arguments, and environment variables are accepted
• Supports multiple commands connected via pipes
• Input/output redirections must follow shell syntax
• Actions and updates are handled in real time through the terminal
• The shell exits cleanly with the exit command

Build & Run

1. Clone the Module Directory

git clone https://github.com/Yuxin29/minishell.git minishell
cd minishell

2. Compile and Run Your Program

make

Other available commands:

make clean   # Remove object files
make fclean  # Remove object files and executable
make re      # Recompile everything from scratch

3. Running the Program
4. The shell will start and prompt the user to enter commands.

./minishell

Example:

minishell$ ls -l | grep txt > output.txt
# This executes the pipeline with proper redirection and stores the output in output.txt.

Notes

• The shell handles multiple commands, pipelines, and redirections in a way similar to a real Unix shell.
• Environment variables and built-in commands are fully supported.
• Memory management and error handling are carefully implemented to prevent leaks and crashes.

co-developer

This project was developed in collaboration with Lin-0096 Lin Liu.