This minimal shell runs in an infinite loop, displaying a prompt (->) to the user as a signal to input a command line.
It then parses the command, tokening it into arguments ready for execution.
Should the user input nothing or any string of characters that doesn't match a known command, our shell will behave similarly to the standard shell, printing error messages or prompting again as appropriate.

The rules we followed

• Edition was made on VS code.
• We put a lot of effort to built a beautiful and fonctional README.
• To have a nice, readable and easily understandable code we followed the Betty coding style.
• To serve this purpose we separated as much as possible the different functions on different files
• We used system calls only when needed.
• We fought the memory leaks with honor and tenacity, and although suffering huge losses on this battlefield, we won in the very end.
• FYI : We wanted to add a nice and unique personnality to our shell but unfortunately all of our strength was focused on defeating our enemy, Sir Valgrind the Ruthless.

Understanding our Shell

Man page

The man page can be invoked with the following command:

man ./hsh_man

Flowchart

A picture is worth a thousand words (at least, we hope so).

Structure of files

File name	Description
.gitignore	File containing all the tests and executable files
_gentenv.c	Function to get the value of the passed environment variable
AUTHORS	File containing information about the project contributors
checkarg.c	Function that analyzes the first argument passed to the program
get_path.c	Finds the directory in which the passed command has been found
hsh_man	Manual page of hsh
main.c	Main function (program entry point)
pr_env.c	Function that prints the environment variables to stdout
README.md	Project description and usage information
simple_shell.h	Header file containing all used functions and libraries
spoon.c	Function that launches a fork process

Uses and tests

Compiling

Compile using following command :

gcc -Wall -Werror -Wextra -pedantic -std=gnu89 *.c -o hsh

These ensured we would catch all possible issues and that our shell would have good portability.

Usage

Simply invoke it with ./hsh, wait for the welcome message and prompt to show (it won't take long, we promise!) then type in your commands.
Note that it works both interactively and not, like so:

User@Ubuntu:/$ ./hsh
Hi there!
-> ls
AUTHORS _getenv.c checkarg.c get_path.c hsh images main.c pr_env.c simple_shell.h spoon.c
-> exit
See you next time!
User@Ubuntu:/$ echo "/bin/ls" | ./hsh
AUTHORS _getenv.c checkarg.c get_path.c hsh images main.c pr_env.c simple_shell.h spoon.c

Functionalities

This simple shell takes into account two built-ins: exit and env. Typing exit will close the shell, and env will print the contents of the environment variable.
It can also be used for basic commands sur as ls, cp, rm, or pwd, the latter being both a built-in and a binary command.
Here are some of them in action:

As shown, there is no need to input the path to the desired commands' location, as PATH is handled.

Possible improvements and known bugs

• The cd command has not been implemented at this date.

Authors

Your most obliged and humble servants:
Priam Demailly
Sarah Wacquiez