Minishell is a simplified shell implementation developed as a project for the 42 São Paulo Common Core curriculum. It replicates basic functionalities of a Unix shell, such as executing commands, handling pipes, redirections, and managing signals, while providing an interactive command-line interface. Built in C, Minishell aims to mimic the behavior of Bash, focusing on process management, input parsing, and environment variable handling.
Credits:
This project was a collaborative effort for the 42 São Paulo curriculum.
42 São Paulo is a tuition-free, global coding school emphasizing peer-to-peer learning and project-based education. This project sharpens algorithmic thinking and optimization skills in C.
Minishell is a single program that provides an interactive command-line interface to execute commands, manage environment variables, and handle input/output redirections. It is divided into:
- Mandatory Part: implements a shell with command execution, built-in commands, pipes, redirections, and signal handling.
- Bonus Part: adds advanced features like logical operators (&&, ||), wildcard expansion (*), and command grouping with parentheses
().
- Command Execution: runs external commands using
execve, resolving paths viaPATH. - Built-in Commands:
echo: prints text, with-noption support.cd: changes directories (relative/absolute paths).pwd: displays the current working directory.export: sets or lists environment variables.unset: removes environment variables.env: displays environment variables.exit: exits the shell with a status code.
- Pipes: supports pipelines (e.g.,
ls | grep txt) with proper subprocess and file descriptor management. - Redirections: handles
<,>,>>, and heredoc (<<) for input/output. - Environment Variables: expands variables (e.g.,
$HOME) and manages the environment. - Signal Handling: manages
Ctrl+C(new prompt),Ctrl+D(exit), and ignoresCtrl+\. - Error Handling: outputs "Error" for invalid inputs, syntax errors, or file issues.
- Bonus Features:
- Logical operators (
&&,||) for conditional execution. - Wildcard (
*) expansion for file matching. - Parentheses
()for command grouping.
- Logical operators (
- Written in C, compliant with the 42 Norm.
- No unexpected crashes (e.g., segmentation faults).
- No memory leaks from heap allocations.
- Compiled with
-Wall -Wextra -Werror. - Uses the
readlinelibrary for input handling.
- C compiler (e.g.,
gccorclang). makeutility.readlinelibrary:- Debian/Ubuntu:
sudo apt-get install libreadline-dev - macOS:
brew install readline
- Debian/Ubuntu:
-
Clone the repository:
git clone https://github.com/LuizGandra/minishell.git cd minishell -
Build the mandatory part:
make
-
Run
minishell:./minishell
-
Build the bonus part (optional):
make bonus
-
Exit the shell with
exitorCtrl+D.
make clean: remove object files.make fclean: remove the program and object files.make re: rebuild everything.
include/*.h: header files.src/main.c: main entry point of the program.src/builtins/*.c: source files for built-in command implementations (e.g., echo.c, cd.c).src/exec/*.c: source files for command execution logic (e.g., exec.c).src/expander/*.c: source files for variable expansion and wildcard handling (e.g., expander.c).src/lexing/*.c: source files for tokenization and syntax analysis and validation (e.g., lexer.c).src/parser/*.c: source files for command parsing and tree building (e.g., parser.c).src/signals/*.c: source files for signal handling (e.g., signals.c).src/utils/*.c: utility functions (e.g., string handling, memory management).Makefile: compilation automation.libs/libft/: directory for the libft library.
This project is part of the 42 curriculum and intended for educational use.