/Mini-SHELL

My implementation for SHELL in C, which supports redirections, pipes, environ, etc. It's as beautiful as shell 🐚

Primary LanguageCMIT LicenseMIT

Want to explore some cute shells [ 🐚 ] ? Then, dive into the Occean.

WHAT IS IT, MINISHELL !?

Where There is a SHELL, There is a Way

GitHub code size in bytes


  • Our first group project during my time at 42, which I collaborated on with @reogine.
  • 42 project, recoding our own little bash. A program capable of parsing (which I have done ) a prompt and launching executables with arguments, along with a few built-in functions.
  • The objective of this project is to create a simple shell to learn some advanced programming techniques like processes creation and control, file descriptors, signals and pipes, etc.

WHY?

The existence of shells is linked to the very existence of IT.

At the time, all developers 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 of creating a software to communicate with a computer using interactive lines of commands in a language somewhat close to the human language.

Thanks to Minishell, you’ll be able to travel through time and come back to problems people faced when Windows didn’t exist.

GitHub code size in bytes


Built-in functions to implement :

Command Description
echo Echo the STRING(s) to standart output. -n flag: do not output the trailing newline.
cd Change the shell working directory (with a relative or absolute path).
pwd Print name of current/working directory.
export Set export attribute for shell variables.
unset Unset values of shell variables.
env Print the environment.
exit Cause the shell to exit with the exit status specified.

Using Only :

Only the following functions are allowed to be used in this project:

Function Description Function Description
readline read a line from the terminal lstat get file status
rl_clear_history clear the history list by deleting all of the entries fstat get file status by fd
rl_on_new_line tell the update routines that we have moved onto a new line unlink remove a specified file
rl_replace_line replace the contents of rl_line_buffer with text execve execute program
rl_redisplay change what's displayed on the screen dup duplicate a file descriptor
add_history save the line in a history list of lines dup2 duplicate a file descriptor
printf format and print data pipe create pipe
malloc allocate dynamic memory opendir open a directory
free free dynamic memory readdir read a directory
write write to a file descriptor closedir close a directory
access check user's permissions for a file strerror return string describing error number
open open and can create a file perror print a system error message
read read from a file descriptor isatty test whether a file descriptor refers to a terminal
close close a file descriptor ttyname return name of a terminal
fork create a child process ttyslot find the slot of the current user's terminal in some file
wait wait for process to change state ioctl control device
waitpid wait for process to change state getenv get an environment variable
wait3 wait for process to change state tcsetattr control asynchronous communications ports
wait4 wait for process to change state tcgetattr control asynchronous communications ports
signal ANSI C signal handling tgetent termcap database emulation
sigaction examine and change a signal action tgetflag termcap database emulation
kill send signal to a process tgetnum termcap database emulation
exit cause normal process termination tgetstr termcap database emulation
getcwd get current working directory tgoto termcap database emulation
chdir change working directory tputs curses interfaces to terminfo database
stat get file status by pathname

FOR MORE INFORMATION, CHECK THE SUBJECT : MINISHELL SUBJECT


About this repo:

  1. Clone the repo.
  2. Execute make command.
  3. Execute ./bin/minishell
  4. You will get prompted. then, it's our shell, have fun with it.

Useful ressources :


the most highlighted learned skill from this project is "How to fix memory leaks, and memory management".

                                               We struggled but we learned :)