A lightweight, functional Unix shell written in C. This project demonstrates core systems programming concepts, including process lifecycle management, inter-process communication (IPC), and low-level file descriptor manipulation.

• Process Execution: Supports running any external Linux binary by leveraging fork() and execvp().
• I/O Redirection: Implements output redirection (>) by manipulating file descriptors with dup2().
• Command Piping: Supports inter-process communication via pipes (|), allowing the output of one process to serve as the input for another.
• Built-in Commands: Native support for cd (Change Directory), help, and exit to manage the shell environment.
• Robust Error Handling: Custom error reporting using perror for system call failures.

The shell operates on a REPL (Read-Eval-Print Loop) architecture:

1. Tokenization: User input is parsed into a null-terminated array of strings using strtok.
2. Process Management: For external commands, the shell creates a child process. The parent process synchronizes using wait() or waitpid().
3. Pipe Implementation: When a pipe is detected, the shell initializes a kernel buffer via pipe(), forks two concurrent child processes, and reassigns their standard streams.

• GCC Compiler
• Linux Environment (tested on Linux Mint/Ubuntu)

1. Clone the repository:

   git clone [https://github.com/AT95BL/At95-Shell.git](https://github.com/AT95BL/At95-Shell.git)
   

2. Compile the source code: gcc shell.c -o shell

3. Run the shell: ./shell