yaten / 42-minishell

🐚 The objective of this project is to create a simple shell in C.

About Minishell

This is the eighth project in the 42 Cadet Curriculum. Minishell is about creating a simple shell with limited external functions.

As beautiful as a shell.

External functs.

readline, rl_clear_history, rl_on_new_line, rl_replace_line, rl_redisplay, add_history, printf, malloc, free, write, access, open, read, close, fork, wait, waitpid, wait3, wait4, signal, sigaction, sigemptyset, sigaddset, kill, exit, getcwd, chdir, stat, lstat, fstat, unlink, execve, dup, dup2, pipe, opendir, readdir, closedir, strerror, perror, isatty, ttyname, ttyslot, ioctl, getenv, tcsetattr, tcgetattr, tgetent, tgetflag, tgetnum, tgetstr, tgoto, tputs

Group

Made with <3 by:

• Willian Lima (@willianlim)
• Paulo Rafael Ramalho (@Yaten)

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Installation & Usage

Requirements

The only requirements are:

• GNU make (v4.2.1)
• GCC (v9.4.0)

Those versions are the ones used during development.

Building the program

1. Download/Clone this repo

    git clone https://github.com/willianlim/Minishell
   

2. cd into the root directory and run make

    cd Minishell
    make
   

Running the program

1. After building the source, run ./bin/minishell from the project root.

    ./bin/minishell
   

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Mandatory part

• Display a prompt when waiting for a new command.
• History.
• Search and launch the right executable.
• Only one global variable.
• Not interpret unclosed quotes or special characters which are not required by the subject.
• Handle ’ (single quote) which should prevent the shell from interpreting the metacharacters in the quoted sequence.
• Handle " (double quote) which should prevent the shell from interpreting the metacharacters in the quoted sequence except for $ (dollar sign).
• Handle environment variables ($ followed by a sequence of characters) which should expand to their values.
• Handle $? which should expand to the exit status of the most recently executed foreground pipeline.
• Handle ctrl-C, ctrl-D and ctrl-\ which should behave like in bash.

In interactive mode:

• ctrl-C displays a new prompt on a new line.
• ctrl-D exits the shell.
• ctrl-\ does nothing.

Implemented builtins

• echo with option -n
• cd with only a relative or absolute path
• pwd with no options
• export with no options
• unset with no options
• env with no options or arguments
• exit with no options

Implemented redirections

• < redirect input.
• > redirect output.
• << with a delimiter, then read the input until a line containing the delimiter is seen.
• >> redirect output in append mode.
• Pipes (| character). The output of each command in the pipeline is connected to the input of the next command via a pipe.

Yes, my own little bash! :D

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Reference

• links