Ask HN: How to learn proper systems programming? • Hacker News Board

Re: Ask HN: How to learn proper systems programming?

#21

Post by matheusmoreira » Mon, Jun 21, 2021, 12:54 PM UTC

Start using your operating system directly instead of relying on libraries to do things for you. Learn Linux system calls and use them for everything. A great way to do this is to compile your C code in freestanding mode and with no libc. You'll have to do everything yourself.

It is easy to get started. Here's a system call function for x86_64 Linux:

https://github.com/matheusmoreira/liblinux/blob/master/sourc...

With this single function, it is possible to do anything. You can rewrite the entire Linux user space with this.

The Linux kernel itself has a nolibc.h file that they use for their own freestanding tools:

https://github.com/torvalds/linux/blob/master/tools/include/...

It's even better than what I came up with. Permissively licensed. Supports lots of architectures. There's process startup code so you don't even need GCC's startfiles in order to have a normal main function. The only missing feature is the auxiliary vector. You can just include it and start using Linux immediately.

You can absolutely do this with Rust as well. Rust supports programming with no standard library. If I remember correctly, the inline assembly macros are still an unstable feature. It's likely to change in the future though.

Re: Ask HN: How to learn proper systems programming?

#22

Post by ketanmaheshwari » Mon, Jun 21, 2021, 1:01 PM UTC

Take a look at the APUE course: https://stevens.netmeister.org/631/

Re: Ask HN: How to learn proper systems programming?

#23

Post by vivek_sg » Mon, Jun 21, 2021, 1:11 PM UTC

Hello there I have quite similar background. (10 years experience, in backend and native android development). Most of the comments already contain good advice. Systems Engineering takes time. I followed long route. I initially took some course in digital logic, and computer architecture and than later took following OS courses.

1. https://pdos.csail.mit.edu/6.S081/2020/schedule.html (check video links and do all the lab assignments)

2. https://www.youtube.com/watch?v=dEWplhfg4Dg&list=PLf3ZkSCyj1... (based on old MIT 6.828)

3. Networks Review (self study)

Somebody mentioned Intel manuals in the comment (those are really helpful)

These courses helped alot. I would suggest to take some firmware and device driver development course as well. My conclusion is that, these are tough skills and the learning process can be accelerated if you can find some entry level position in a small company which do this kind of work.

Re: Ask HN: How to learn proper systems programming?

#24

Post by zer0faith » Mon, Jun 21, 2021, 1:12 PM UTC

If you know folks in your company are writing things you are interested in reach out. Most of those people are happy that someone is taking interest in what they are doing. The information that they will provide will be meaningful and valuable. Use what you learn from those conversations and leverage it in your daily job functions to better position yourself for future roles/jobs/projects.

Re: Ask HN: How to learn proper systems programming?

#25

Post by shipp02 » Mon, Jun 21, 2021, 1:15 PM UTC

Just to check my own knowledge. Do you mean opening another socket for logs?

If not, what is a channel?

Re: Ask HN: How to learn proper systems programming?

#26

Post by _huayra_ » Mon, Jun 21, 2021, 1:31 PM UTC

vivek_sg wrote: post #23

Hello there I have quite similar background. (10 years experience, in backend and native android development). Most of the comments already contain good advice. Systems Engineering takes time. I followed long route. I initially took some course in digital logic, and computer architecture and than later took following OS courses. 1. https://pdos.csail.mit.edu/6.S081/2020/schedule.html (check video links and do all the…

I just completed the xv6 projects for that course and they were damn difficult, but taught me a lot. I highly recommend it.

The only thing I missed was support for when I really ran into a wall, but perhaps I just don't know the right irc channel.

Re: Ask HN: How to learn proper systems programming?

#27

Post by vivek_sg » Mon, Jun 21, 2021, 1:37 PM UTC

_huayra_ wrote: post #26

vivek_sg wrote: post #23

Hello there I have quite similar background. (10 years experience, in backend and native android development). Most of the comments already contain good advice. Systems Engineering takes time. I followed long route. I initially took some course in digital logic, and computer architecture and than later took following OS courses. 1. https://pdos.csail.mit.edu/6.S081/2020/schedule.html (check video links and do all the…

I just completed the xv6 projects for that course and they were damn difficult, but taught me a lot. I highly recommend it. The only thing I missed was support for when I really ran into a wall, but perhaps I just don't know the right irc channel.

I totally agree on that. I tried the old version (intel based). And it to me quite some time to do the projects. But I learned a lot in the process.

Re: Ask HN: How to learn proper systems programming?

#28

Post by rubicks » Mon, Jun 21, 2021, 1:38 PM UTC

From personal experience, what made low-level concepts "click" for me was looking at documentation for linkers and the various ELF tools. Once I could see the "ends", it gave me the inspiration to dig into the "means". Ymmv, of course.

Re: Ask HN: How to learn proper systems programming?

#29

Post by ghoward » Mon, Jun 21, 2021, 1:40 PM UTC

If you want to learn Rust for systems programming, first learn C and write something non-trivial in it. Then run it through Valgrind [1] with your test suite. You can also try the sanitizers (AddressSanitizer, MemorySanitizer, UndefinedBehaviorSanitizer, ThreadSanitizer, etc.).

This will teach you what Rust is saving you from and help you understand how it does it.

[1]: https://www.valgrind.org/

Re: Ask HN: How to learn proper systems programming?

#30

Post by swiftcoder » Mon, Jun 21, 2021, 1:46 PM UTC

> I had a Rust job for around half a year, where people build web servers and came from a C and C++ background. Half of the stuff they wrote I didn't understand (flushing, opening another channel just for logs so we don't fill up the other ones etc. etc.)

I think it's worth mentioning that the majority of topics involved in this type of webserver work wouldn't necessarily be covered by a systems programming book. There's obviously overlap between all of systems programming, networking, and concurrent/distributed systems, but if you plan to focus on web servers, I'd pick up texts on the other topics as well.