Minishell is a 42 school team project to create a basic shell program in C. It implements redirections and pipes, as well as environment variable expansions and the cd
, echo
, env
, exit
, export
, pwd
and unset
builtin commands.
This project has been archived in the state it was in at the time of evaluation.
Validated 11/11/2022. Grade: 99%.
Clone the repository with the minitester submodule:
git clone --recurse-submodules [email protected]:mcombeau/minishell.git
To compile:
cd minishell && make
To run the program:
./minishell
A prompt will appear. You may enter your commands to be executed.
To run the included tester:
cd minitester/ && bash minitester.sh
Minishell is a miniature shell program based on Bash. Minishell supports:
- Prompt display
- Command history (up and down arrows)
- System executables available from the environment (
ls
,cat
,grep
, etc.) - Local executables (
./minishell
) - Builtin commands :
echo
(and option-n
)cd
(with only a relative or absolute path)pwd
(no options)export
(no options)unset
(no options)env
(no options or arguments)exit
(with exit number but no other options)
- Pipes
|
which redirect output from one command to input for the next - Redirections:
>
redirects output>>
redirects output in append mode<
redirects input<< DELIMITER
displays a new prompt, reads user input until reachingDELIMITER
, redirects user input to command input (does not update history)
- Environment variables (i.e.
$USER
or$VAR
) that expand to their values.$?
expands to the exit status of the most recently executed foreground pipeline.
- User keyboard signals:
ctrl-c
displays a new prompt line.ctrl-d
exits minishellctrl-\
does nothing
However, Minishell does not support \
, ;
, &&
, ||
, or wildcards.
🇺🇸 Articles in English about the concepts tackled in this project:
- Creating and Killing Child Processes in C
- Pipe: an Inter-Process Communication Method
- Sending and Intercepting a Signal in C
- Handling a File by its Descriptor in C
- Errno and Error Management in C
🇫🇷 Articles en français sur les concepts abordés dans ce projet :
- Créer et tuer des processus fils en C
- Pipe : une méthode de communication inter-processus
- Envoyer et intercepter un signal en C
- Manipuler un fichier à l’aide de son descripteur en C
- Errno et la gestion d’erreur en C
Other useful links:
- Bash reference manual
- Introduction to Systems Programming: a Hands-on Approach, Chapter 5. Writing Your Own Shell
- Stephen Brennan's Tutorial - Write a Shell in C
- The Open Group Base Specifications, Shell Command Language
- A Guide to Unix Shell Quoting
- Austin Tripp's Quick Tutorial on Bash Quotes
Made by aquesada and mcombeau