Void Shell

Overview

Void Shell, or Vsh, is a custom, simple Unix-style shell focusing on speed, minimalism, and clarity.

Features

• Minimal Builtin Set – Unix model is preserved and overlap with existing utilities is prevented.
• Recursive-Descent Parser – Semantics are clear, controllable, and extensible.
• Builtin Debug Modes – Display token streams and AST structure for convenience.
• Modular Architecture – New features and extensions are easily accommodated.

Examples

Commands

Standard Unix commands work as usual:

vsh> pwd
/your/current/path
vsh> echo hello world
hello world
vsh> echo hello; echo world
hello
world
vsh> echo hello world | tr a-z A-Z
HELLO WORLD

Debug Builtins

Debug commands require the input to be passed as a single quoted string.

For example, using tokens:

vsh> tokens "echo hello world"
4 | WORD 'echo'
10 | WORD 'hello'
16 | WORD 'world'
16 | EOF

And using ast:

vsh> ast "echo hello world"
SEQUENCE
    ╰ PIPELINE
        ╰ COMMAND (ECHO) ["hello", "world"]

Installation

Prerequisites

• POSIX-compatible system
• C compiler supporting C17
• CMake 3.20+

Building

1. Clone the repo:

   git clone https://github.com/williamalexakis/void-shell.git
   cd void-shell

2. Build the project:

   mkdir build
   cd build
   cmake ..
   cmake --build .

Usage

To get started, run the executable and use help to see all builtin commands.