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Show HN: A DOS-like hobby OS written in Rust and x86 assembly

(github.com)
207 points krustowski | 1 comments | 19 Jun 25 13:38 UTC | HN request time: 0.21s | source

To try it out, simply build the project yourself from source, or use attached bootable ISO image of the system (in Releases on Github) and run it in QEMU.

https://blog.vxn.dev/rou2exos-rusted-edition

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OhNotAPaper ◴[19 Jun 25 21:41 UTC] No.44322773[source]▶
Out of curiosity, why x86? Is it the preponderance of resources? The weird instruction format? The complexity of the boot sequence? Are you specifically trying to mimic DOS?

> A support for the ARM architecture (aarch) is coming soon too.

Wow! How do you support a DOS-like OS across multiple architectures when DOS itself is tightly tied to interactions among the program, the system code, and the architecture?

replies(2): >>44323939 #>>44325826 #
1. anyfoo ◴[20 Jun 25 01:15 UTC] No.44323939[source]▶
I have not looked at this project, but my guess would be: x86 is a widely available platform that, because of its history and relentless compatibility, contains a lot of legacy interfaces that make implement a very simple, thin-layer and “DOS-like OS” without the need to parse device trees, set up MMUs, deal with complex busses like PCI(e) and so on.

It is much harder to bootstrap a simple OS in ARM, and it won’t stay very simple unless you accept significantly more limitations than you would under x86. (For example, you can’t do very much with the MMU off on ARM, and you also don’t have convenient BIOS interfaces that allow you to, say, read a sector, or wait for a keypress, with just a few lines of assembly).