Mini Shell (msh)

A simple shell program (msh) implemented in C that mimics the behavior of the BASH shell. This project is built using Linux Kernel system calls and IPC mechanisms.

Features

1. Prompt Customization:

   • Default prompt: msh >
   • Can be customized using the PS1 environment variable (e.g., PS1=NEW_PROMPT).
   • Prevents spaces between = (e.g., PS1 = NEW_PROMPT is treated as a normal command).

2. Command Execution:

   • Executes both internal and external commands.
   • Creates a child process for external commands, waits for its completion before displaying the prompt again.

3. Special Variables:

   • echo $?: Prints the exit status of the last executed command.
   • echo $$: Prints the PID of the msh process.
   • echo $SHELL: Prints the executable path of the msh program.

4. Signal Handling:

   • Ctrl+C: Sends SIGINT to the foreground program. If no program is running, it redisplays the prompt.
   • Ctrl+Z: Sends SIGTSTP to the foreground program and displays its PID.

5. Built-in Commands:

   • exit: Terminates the msh program.
   • cd: Changes the working directory.
   • pwd: Displays the current working directory.

Requirements

• Linux OS
• GCC compiler

How to Run

1. Clone the repository:

   git clone https://github.com/your-username/msh.git
   cd msh