Project lead here. I haven't had time in the last few weeks to work on this, so the book is pretty far behind the kernel itself at the moment. Playing the long game. I was hoping to do some more today, in fact...
I'm reading through now, and would love to contribute. I've been trying to break into this space (systems programming, especially OS and compilers) for a long time and the biggest hurdle for me has been to actually do it. I really appreciate that this project is focused on explaining just enough to jump in, complemented with nods to further resources that can add on to whatever knowledge the reader brings.
Steve, thanks for all your work on this and with Rust. Your attitude toward teaching and your writing ability go a long way in encouraging people to learn and in having the lesson be worthwhile.
The "everything is a URL" concept is interesting. QNX uses pathnames in a somewhat similar way; programs with the privilege to do so can register to own some portion of the pathname space, and requests with such pathnames go to that program. The kernel has no idea what pathnames mean. This gets file systems out of the kernel. It looks like Redox is doing something similar, but not enough of the documentation is written yet for me to tell quickly.
Steve, thanks for all your work on this and with Rust. Your attitude toward teaching and your writing ability go a long way in encouraging people to learn and in having the lesson be worthwhile.