Xous is a microkernel operating system with processes, threads, and messages. It is designed to have an extremely small kernel that delegates as much as possible to userspace. This book describes the operating system kernel as well as the services that support normal operating system behavior.

As this book is a work in progress, some chapters are placeholders and will appear blank.

The book is written for two audiences: kernel maintainers, and application developers.

• Chapters 2 (Server Architecture),

  • 3 (Introducing the Kernel), and
  • 5 (System Startup) are primarily for kernel maintainers and system programmers.

• Chapters 1 (Getting Started),

  • 4 (Renode Emulation),
  • 6 (Build System Overview),
  • 7 (Messages) and
  • 8 (Graphics) are more appropriate for application developers.

• Chapter 9 (PDDB) covers the Plausibly Deniable DataBase, and has sub-sections for both kernel and application developers.