book VS openqnx

Are you saying that this book is a hallucination? And this? And all of this?

4) C++: it’s often overly complicated for many projects. Use with caution, although it’s definitely useful in very large projects. But there’s a reason Rust is increasingly popular for embedded — here’s an engineer’s view.

If you come from the embedded C community then maybe something like Phil Oppermann's writing an OS in Rust series. There's also the embedded Rust book and the embedded Rust working group github that has a lot of resources.

I genuinely don't know why you would say that and I know you were talking about microcontrollers

The rust embedded book: https://docs.rust-embedded.org/book/

It’s not a job, but I’m guessing you would like this book: https://docs.rust-embedded.org/book/

There's a page on the Rust website on embedded systems. Given that you are already familiar with embedded programming, you can probably start with the embedded rust book.

Are you saying that the QNX kernel is not used on embedded devices? It doesn't use C++. (according to GitHub it is 1.8% C++ but I'm assuming that's vendored or demo stuff)

I don't have numbers, but the key ingredient is really minimizing context switches. This also results in priority inheritance while message passing which means that a high priority process gets the answer with it's own high priority, even if sending a message to a low priority process. Very smart.

Teading the old open sourced sources can be quite interesting...

https://github.com/vocho/openqnx/tree/master/trunk/lib/qnx43...