The existence of shells is linked to the very existence of IT. At the time, all coders agreed that communicating with a computer using aligned 1/0 switches was seriously irritating. It was only logical that they came up with the idea to communicate with a computer using interactive lines of commands in a language somewhat close to english. The objective of this project is to create a simple shell in C.
This project is a 42 school's duo project. The core achievement of the project was that it helped us get to the core of the Unix system and explore an important part of this system’s API: process creation, input parsing and synchronisation.
The behavior of the minishell is heavily based on the bash behavior. For every point, take bash as a reference. It is implemented with the rules described below.
implement the following builtins:
echoand the-noptioncdonly with an absolute or relative pathpwdwithout any optionsexportwithout any optionsunsetwithout any optionsenvwithout any options or argumentsexitwithout any options
The function to be implemented in the project
- Display a prompt while waiting for a new order.
- Find and launch the correct executable (based on a PATH environment variable or using an absolute path).
<<in the command line must open a heredoc and take input like bash.’and"must work as in bash, except multiline.- The
<,>and>>redirectionss must work as in bash, except for aggregations of fd. - Pipes redirections
|. - The environment variables ($ followed by characters) must work.
$?variable.ctrl-C,ctrl-Dandctrl- \signals should have the same behavior.
⚠️ Warning: Don't copy/paste code you don't understand: it's bad for you, and for the school.
The current project is built for Linux. If you want to run it on Mac, please change the Makefile accordingly by specifying the place of the needed libraries (for example readline).
The project consists of several folders that are presented below.
includes: The following folder contains the minishell.h file, which consists of the includes of external libraries, function headers created in this project and the declaration of the structs used in the project.
libft: This folder represents the library created during the Libft 42 project. It contains many useful functions that helped during the project.
srcs: This folder contains the main functions of the project.
`main.c:` The main function of the project.
`signal.c:` The functions used for signal handling.
`execute.c:` The file that contains the ft_exec function.
`parse_and_execute.c:` The file that is responsible for parsing the line and executing the commands.
`parse:` The folder containing all the files related to parsing.
`env:` The folder containig util functions workig with environment variables.
`builtins:` The folder containing the implementations of the builtin commands.
`heredoc`: The folder containing the function related to heredoc and its execution
utils: This folder contains the util functions used by this project.
To use this project you need to clone this repository, by running the following command
git clone https://github.com/42YerevanProjects/42_minishell.git
Then you should go to the cloned repo and run the make command
cd 42_minishell
make
After that you will see the executable minishell. Lastly you should run the executable
./minishell
You will be provided with a prompt and can use it as a shell.
We got help from a 42 school student aisraely. He gave us a lot of info about the project and code organization. The people who completed the project are 42 studens shovsepy and abalaban.
In order to understand the project requirements well you can read the subject file of the project. Moreover, if you copy the code from this repository then you have to specify the author of the code and referrence this repository. If you find any bugs in the code please write to the issues.