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Comment by dmitrygr | Hacker News Reader

Same as C. Rust is basically C with hardcoded checks enforced and put in by compiler that good programmers already know to put in.

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Given all the vulnerabilities that have happened with C code over the years, I think making it harder for programmers to screw up is a win.

while it's true that Rust has the potential to decrease the frequency and impact of certain types of bugs, i think the GP was saying that Rust's borrow checker is unlikely to revolutionize the way operating systems are designed and the way userspace interacts with the kernel.

the GP fails to acknowledge Rust's other features such as its type system, but i'm not convinced those will revolutionize operating system architecture either.

that doesn't mean i'm not excited about the potential of a new open-source general purpose operating system kernel written in Rust and entering the same space as the Linux kernel. it seems like a good fit for the language and an area where modernization is past due.

Fair enough, I definitely agree with everything you're saying. I took a little issue with the statement that "good programmers" know how to properly write safe C good though, as it not only is unnecessarily condescending but also glosses over the fact that even good programmers write code with bugs, and "knowing how" to do something properly doesn't mean you'll do it properly 100% of the time.

You're missing some things. For example, the APIs you can expose in Rust can encode significantly more information than a C-based one can, given the strength of its typesystem.

Of course, Rust doesn't have a stable ABI yet, but then again, neither do many OSes. We'll get there!

I was thinking something similar. Maybe I can pass a userspace closure into the kernel? Maybe I don't need the memory manager to be as beefy? Maybe the API can be fully reactive (idk if this is good or not).

One thing, and one that's relevant to an OS class, that I've been doing with my own toy kernel (that I haven't had any time for lately) is using Cargo workspaces to make it extremely modular. You can of course do this in C, but it's even easier with Cargo. In a class context, you could do something like "here's the entire OS except the scheduler package, implement it and make all the tests pass."

This is true. I wonder if we'll see an OS where each of these modules has some sort of monadic (or maybe something else) API so that you can really decouple the implementation from the API.

This exists: https://ocw.mit.edu/courses/mathematics/18-s996-category-the...

Actually, it is more like "Same as Ada", but with curlys (oversimplifying here).

> Rust is basically C with hardcoded checks enforced and put in by compiler that good programmers already know to put in.

I have a feeling you know absolutely nothing about rust.

Even the best programmers and programs in C have issues with what the borrow checker will catch. Moreover, the expressiveness of the type system is world's above and beyond any other main-stream (so not Haskell or ocamel) language. Saying it's C with checks is like saying French and Hungarian are the same, but with some different words.

> I have a feeling you know absolutely nothing about rust.

Please edit uncivil swipes out of your comments here. The rest of what you wrote is fine.

I think you are correct about Rust being substantially different from C, but that's a nasty way of saying it ("you know absolutely nothing about..."). Is it really necessary to speak that way?

It wasn't that nasty. Might just be because I have no sympathy for people saying things like they are fact, yet don't know what they are talking about.

Except the context of the quote was OS architecture so dmitrygr was correct -- Rust will not provide different OS architectures.

Moreover, it was mean-spirited. Probably because they were reacting to the second part of dmitrygr's quote.

On a fundamental level, sure, a new language doesn't inherently make a new architecture possible. But you have to think of it from an affordance perspective: what architecture does Rust make easier or better?

Consider the Stylo project in Firefox, for example. Yes, Mozilla could have done the parallelization in C++ instead of Rust. They even tried! Twice! But it failed both times. That doesn't mean that it's impossible.

In my experience, this is what people mean when they say things like this.

Sure, but you're moving the goalposts :)

Look, I'm a big fan of Rust - I want to see it succeed. I go to Rust meetups in my city, I've advocated for it's adoption in my company, yadda yadda. But I don't these vague half-truths are good for the language or the community. In fact, I think they'll be harmful to the community over time as the language will fail to live up to expectations. When I started programming, Java was in the position of Rust. It was being given so many vague platitudes that it experienced push back a few years later as developers realized it didn't fix all their problems.

I don't mean for this post to be mean or condescending. Tone is hard to transmit over the internet.

I don’t think it’s moving the goalposts. It’s where they were set in the first place. Furthermore, nobody is making promises of solving all the problems, the OP said they were interested to see what might happen, which is a very different statement than “this will happen” or “this will happen and fix everything.”

That is, I 100% agree with your comment, but I don’t see it happening in this thread.

How is that a vague half truth? Just because it’s not concrete doesn’t mean it’s either vague or only half true

Well, that's a bit not nice.

I took the "Rust is like C" line to mean is that you can use Rust anywhere you can use C, running at C speeds (the whole zero cost abstraction/no runtime/unsafe blocks), someone that can't be said about OCaml/F#/Haskell (TTBOMK).

EDIT

Moreover, if you look at context, you'll see that his point is that when it comes to OS design, a rust based OS will look mostly like a C based OS.

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