Cardinal is a hobbyist Operating System designed to be elegant. It takes heavy inspiration from Plan 9 and related OS's.

This repository contains the kernel, userspace build configurations, patches and scripts that are needed to build a working image.

The project is currently in active development. Join us at #Cardinal-OS on Freenode ( irc.freenode.net ) to keep up with development.

The kernel is a mostly complete microkernel. As a result it is fairly small. It responsible for little more than task switching, memory management and interprocess communication.

The userspace of Cardinal is currently in development. It consists of the drivers, servers and user applications. The userspace is divided into 3 rings by the kernel with lower numbered rings having higher privileges.

Ring 0, abbreviated as R0 has near kernel level syscall permissions, this is where the services most core to the system are situated.

The drivers are situated in Ring 1 or R1. This ring has a more restrictions on which syscalls are available to an application.

All other applications run in Ring 2 or R2. This ring has the most restrictions, only allowing applications to make syscalls for shared memory and IPC.

Currently the following have been ported to the OS:

• OpenSSL
• zlib
• libpng

Currently available device drivers:

• Intel HD Audio (WIP)
• VESA Framebuffer (WIP)
• AHCI (WIP - Read Only)
• VMWare SVGA (WIP - Needs an interface)
• RTL8139 (WIP - Needs an interface)
• USB UHCI (WIP - Initialization only)

Execute the scripts/build-os.sh script in the source directory.

Join us at #Cardinal-OS on Freenode ( irc.freenode.net ).