とあるOS (ToAruOS) is a hobby kernel and supporting userspace, built mostly from scratch, in development since December of 2010.

It was originally developed at the University of Illinois at Urbana-Champaign. For a period of time, it was the development focus of the university's SIGOps chapter.

This repository contains the kernel, modules, and core userspace. Some third-party libraries and utilities are required to build a working system - these are automatically retrieved by the build process.

The kernel provides a number of features one would expect from a Unix-inspired project, including process and thread support, ELF binary support, runtime-loaded modules, pipes and TTYs, a virtual file system including virtual /proc (inspired by Plan9 and Linux) and device files, EXT2 filesystem support, signals, and more.

The userspace provides a rich graphical environment with a composited window manager (built on Cairo), a terminal emulator (with support for xterm 256-color modes and Konsole 24-bit color modes, anti-aliased text using FreeType, and general support for some Unicode text), and other graphical demo applications.

The userspace depends on a number of third-party libraries which are outside of the development scope of the project, as well as the newlib C library (though development of an in-house C library is planned).

Some third-party software is provided within this repository:

• cpudet, a cpuid parser.
• VL Gothic, a Japanese TrueType font.
• DejaVu, a series of popular, free TrueType fonts.
• A SHA512 hash library, used in the login applications to provide naïve hashed password support.
• The popular DMZ CC By-SA mouse cursor theme from Novell.
• utf8decode.h, UTF8 decoding tools.
• A port of glxgears.
• Various Curses examples by Pradeep Padala.
• A list of PCI vendor and device names.
• A terminal implementation of the game "2048".

Licenses for these tools and libraries can be found here.

The following external libraries and tools are retrieved during the build process:

• gcc and binutils - For both a cross-compiler and a native port.
• newlib - C library (development of an in-house C library is planned, but has not yet commenced).
• libpng - Used extensively by the native graphics library to provide wallpaper and icons.
• zlib - Dependency of libpng, but also generally useful.
• freetype - For rendering text using TrueType fonts.
• cairo and pixman - For CPU-accelerated graphics.
• ncurses - Terminal control library, provides terminfo.
• Mesa - Implementation of OpenGL (only the software rasterizer is available).
• Vim - Popular text editor.

In addition to the libraries included in the build process, others have been ported or successfully built for とある:

• Lua - Builds as-is
• MuPDF - See klange/toaru-pdfviewer (library must be cross compiled)
• SDL - See klange/SDL
• snes9x-sdl - See klange/snes9x-sdl
• Bochs - Should build as-is, but may require modifications.
• Python - A Python port has been built, but is not yet available.

For additional screenshots, please see the wiki.

Please see Testing and Building on the wiki.

For help building the kernel and userspace, join us in #toaruos on Freenode (irc.freenode.net).