@kat@yarn.girlonthemoon.xyz Oh dear. 😩

@arne@uplegger.eu Stattdessen rutscht er seitlich vom Tisch? 🤪

@lyse@lyse.isobeef.org I can confidently say that I don’t remember ever having seen fireflys. (Nor Firefly.) 😳 I’m most surprised that you could count them. Naively, I would assume that these guys move around a lot and you’d lose track of them?

We’re entering the “too hot to think”-season in 3, 2, 1 … and we’re live!

Welcome to the family, Puffy. 🥳🐡

Image

@lyse@lyse.isobeef.org

They’re all talks, not real hands-on trainings like you did.

I love listening to good, well-structured talks. Problem is, not everybody is a good speaker and many screw it up. 🥴 I’m certainly not a great speaker, which is why I gravitate more towards “workshops”, in the hopes that people ask questions and discussions arise. Doesn’t always work out. 🤣 At the very least, I almost always have some other person connect to the projector/beamer/screenshare and then they do the stuff – this avoids me being wwwwaaaaaaaaayyyy too fast.

We are usually drowned in stress and tight deadlines, hence events like today are super rare … We used to do it more often until ~10 years ago.

Once a year the security guys organize a really great hacking event, though.

Oh dear, I’d love to participate in that. 🤯 That sounds like a lot of fun. (Why don’t we do this?!)

@prologic@twtxt.net This person isn’t particularly happy with this study:

https://mastodon.social/@grimalkina/114717549619229029

I don’t know enough about these things to form an opinion. 🫤 I sure wish it was true, though. 😅

I did a “lecture”/“workshop” about this at work today. 16-bit DOS, real mode. 💾 Pretty cool and the audience (devs and sysadmins) seemed quite interested. 🥳

• People used the Intel docs to figure out the instruction encodings.
  
• Then they wrote a little DOS program that exits with a return code and they used uhex in DOSBox to do that. Yes, we wrote a COM file manually, no Assembler involved. (Many of them had never used DOS before.)
  
• DEBUG from FreeDOS was used to single-step through the program, showing what it does.
  
• This gets tedious rather quickly, so we switched to SVED from SvarDOS for writing the rest of the program in Assembly language. nasm worked great for us.
  
• At the end, we switched to BIOS calls instead of DOS syscalls to demonstrate that the same binary COM file works on another OS. Also a good opportunity to talk about bootloaders a little bit.
  
• (I think they even understood the basics of segmentation in the end.)
  

The 8086 / 16-bit real-mode DOS is a great platform to explain a lot of the fundamentals without having to deal with OS semantics or executable file formats.

Now that was a lot of fun. 🥳 It’s very rare that we do something like this, sadly. I love doing this kind of low-level stuff.

@lyse@lyse.isobeef.org Multi-Threading. Is. Hard. 🤯 And yes, that blog is great. 👌

@lyse@lyse.isobeef.org lol – I explicitly kept them in there so that the code is easier to understand for non-Rust people 🤪😂

@prologic@twtxt.net I’d say: Yes, because in Go it’s easier to ignore errors.

We’re talking about this pattern, right?

f, err := os.Open("filename.ext")
if err != nil {
    log.Fatal(err)
}

Nothing stops you from leaving out the if, right? 🤔

(Of course, if we’re talking about a project you’re doing for a customer and the customer keeps asking for new stuff, then you’re never done, and you have to think ahead and expect changes. Is that what they mean? 🤔)

Saw this on Mastodon:

https://racingbunny.com/@mookie/114718466149264471

18 rules of Software Engineering

1. You will regret complexity when on-call
   
2. Stop falling in love with your own code
   
3. Everything is a trade-off. There’s no “best” 3. Every line of code you write is a liability 4. Document your decisions and designs
   
4. Everyone hates code they didn’t write
   
5. Don’t use unnecessary dependencies
   
6. Coding standards prevent arguments
   
7. Write meaningful commit messages
   
8. Don’t ever stop learning new things
   
9. Code reviews spread knowledge
   
10. Always build for maintainability
    
11. Ask for help when you’re stuck
    
12. Fix root causes, not symptoms
    
13. Software is never completed
    
14. Estimates are not promises
    
15. Ship early, iterate often
    
16. Keep. It. Simple.
    

Solid list, even though 14 is up for debate in my opinion: Software can be completed. You have a use case / problem, you solve that problem, done. Your software is completed now. There might still be bugs and they should be fixed – but this doesn’t “add” to the program. Don’t use “software is never done” as an excuse to keep adding and adding stuff to your code.

Okay, here’s a thing I like about Rust: Returning things as Option and error handling. (Or the more complex Result, but it’s easier to explain with Option.)

fn mydiv(num: f64, denom: f64) -> Option<f64> {
    // (Let’s ignore precision issues for a second.)
    if denom == 0.0 {
        return None;
    } else {
        return Some(num / denom);
    }
}

fn main() {
    // Explicit, verbose version:
    let num: f64 = 123.0;
    let denom: f64 = 456.0;
    let wrapped_res = mydiv(num, denom);
    if wrapped_res.is_some() {
        println!("Unwrapped result: {}", wrapped_res.unwrap());
    }

    // Shorter version using "if let":
    if let Some(res) = mydiv(123.0, 456.0) {
        println!("Here’s a result: {}", res);
    }

    if let Some(res) = mydiv(123.0, 0.0) {
        println!("Huh, we divided by zero? This never happens. {}", res);
    }
}

You can’t divide by zero, so the function returns an “error” in that case. (Option isn’t really used for errors, IIUC, but the basic idea is the same for Result.)

Option is an enum. It can have the value Some or None. In the case of Some, you can attach additional data to the enum. In this case, we are attaching a floating point value.

The caller then has to decide: Is the value None or Some? Did the function succeed or not? If it is Some, the caller can do .unwrap() on this enum to get the inner value (the floating point value). If you do .unwrap() on a None value, the program will panic and die.

The if let version using destructuring is much shorter and, once you got used to it, actually quite nice.

Now the trick is that you must somehow handle these two cases. You must either call something like .unwrap() or do destructuring or something, otherwise you can’t access the attached value at all. As I understand it, it is impossible to just completely ignore error cases. And the compiler enforces it.

(In case of Result, the compiler would warn you if you ignore the return value entirely. So something like doing write() and then ignoring the return value would be caught as well.)

We really are bouncing back and forth between flat UIs and beveled UIs. I mean, this is what old X11 programs looked like:

https://www.uninformativ.de/desktop/2025%2D06%2D21%2D%2Dkatriawm%2Dold%2Dxorg%2Dapps.png

Good luck figuring out which of these UI elements are click-able – unless you examine every pixel on the screen.

@kat@yarn.girlonthemoon.xyz I might give it a shot. 😃

Skimming through the manual: I had no idea that keeping the “up” cursor pressed actually slows you down at some point. 🤦

@aelaraji@aelaraji.com I use Alt+. all the time, it’s great. 👌

FWIW, another thing I often use is !! to recall the entire previous command line:

$ find -iname '*foo*'
./This is a foo file.txt

$ cat "$(!!)"
cat "$(find -iname '*foo*')"
This is just a test.

Yep!

Or:

$ ls -al subdir
ls: cannot open directory 'subdir': Permission denied

$ sudo !!
sudo ls -al subdir
total 0
drwx------ 2 root root  60 Jun 20 19:39 .
drwx------ 7 jess jess 360 Jun 20 19:39 ..
-rw-r--r-- 1 root root   0 Jun 20 19:39 nothing-to-see

@kat@yarn.girlonthemoon.xyz I like the animations in your version much better than the ones from ExtremeTuxRacer. 😊 And there’s no little dance at the end of a race!

https://movq.de/v/7531158962/etr.mp4

I also just noticed that the performance issue doesn’t affect all games. 🤔 Sigh, I’ll just downgrade for the time being. Not in the mood to fiddle with this.

@kat@yarn.girlonthemoon.xyz I guess that qualifies as an “Arch moment”, albeit the first one I encountered. I’m running this since 2008 and it’s usually very smooth sailing. 😅

@lyse@lyse.isobeef.org Yeah, YMMV. Some games work(ed) great in Wine, others not at all. I just use it because it’s easier than firing up my WinXP box. (I don’t use Wine for regular applications, just games.)

Speaking of Wine, Arch Linux completely fucked up Wine for me with the latest update.

• 16-bit support is gone.
  
• Performance of 3D games is horrible and unplayable.
  

Arch is shipping a WoW64 build now, which is not yet ready for prime time.

And then I realized that there’s actually only one stable Wine release per year but Arch has been shipping development releases all the time. That’s quite unusual. I’m used to Arch only shipping stable packages … huh.

Hopefully things will improve again. I’m not eager to build Wine from source. I’d rather ditch it and resort to my real Windows XP box for the little (retro)gaming that I do … 🫤

@kat@yarn.girlonthemoon.xyz lol, oof, well, better than nothing. 🥴 It appears to run quite well. 🤔

@prologic@twtxt.net Ahhh, right, my bad, I could have easily found that. 🤦

There’s also a project page which lists some limitations of this study: https://www.media.mit.edu/projects/your-brain-on-chatgpt/overview/

It certainly sounds plausible. “Use it or lose it.”

@prologic@twtxt.net But is there a source for it? Am I too stupid to use that site? 🤪

@prologic@twtxt.net … or just bullshit.

I’m Alex, COO at ColdIQ. Built a $4.5M ARR business in under 2 years.

Some “C-level” guy telling people what to do, yeah, I have my doubts.

@prologic@twtxt.net This doesn’t cite any sources, might as well be satire. 🤔

@kat@yarn.girlonthemoon.xyz Awww. :( Can you tell why? Missing libraries or does it just segfault?

To really annoy my neighbors and everyone in a 5 mile radius, I might take my Model M and type a blogpost on the balcony. 😈

@aelaraji@aelaraji.com I’d love to have a positive, optimistic reply to that, but … uhm … I don’t. 🤣

@kat@yarn.girlonthemoon.xyz Ooh, I’ve got to bookmark that page. 😃

@aelaraji@aelaraji.com I wish I had the luxury of not reading that junk. 😅 But instead, I have a Mutt hotkey that pipes an HTML mail through elinks … Bah.

@prologic@twtxt.net I’m trying to call some libc functions (because the Rust stdlib does not have an equivalent for getpeername(), for example, so I don’t have a choice), so I have to do some FFI stuff and deal with raw pointers and all that, which is very gnarly in Rust – because you’re not supposed to do this. Things like that are trivial in C or even Assembler, but I have not yet understood what Rust does under the hood. How and when does it allocate or free memory … is the pointer that I get even still valid by the time I do the libc call? Stuff like that.

I hope that I eventually learn this over time … but I get slapped in the face at every step. It’s very frustrating and I’m always this 🤏 close to giving up (only to try again a year later).

Oh, yeah, yeah, I guess I could “just” use some 3rd party library for this. socket2 gets mentioned a lot in this context. But I don’t want to. I literally need one getpeername() call during the lifetime of my program, I don’t even do the socket(), bind(), listen(), accept() dance, I already have a fully functional file descriptor. Using a library for that is total overkill and I’d rather do it myself. (And look at the version number: 0.5.10. The library is 6 years old but they’re still saying: “Nah, we’re not 1.0 yet, we reserve the right to make breaking changes with every new release.” So many Rust libs are still unstable …)

… and I could go on and on and on … 🤣

@lyse@lyse.isobeef.org :‘-(

@lyse@lyse.isobeef.org … because you, me, and that guy over there in the corner are the only three people left using plain-text email. 🫤 (And probably Stallman.)

Fuck me sideways, Rust is so hard. Will we ever be friends?

OpenBSD has the wonderful pledge() and unveil() syscalls:

https://www.youtube.com/watch?v=bXO6nelFt-E

Not only are they super useful (the program itself can drop privileges – like, it can initialize itself, read some files, whatever, and then tell the kernel that it will never do anything like that again; if it does, e.g. by being exploited through a bug, it gets killed by the kernel), but they are also extremely easy to use.

Imagine a server program with a connected socket in file descriptor 0. Before reading any data from the client, the program can do this:

unveil("/var/www/whatever", "r");
unveil(NULL, NULL);
pledge("stdio rpath", NULL);

Done. It’s now limited to reading files from that directory, communicating with the existing socket, stuff like that. But it cannot ever read any other files or exec() into something else.

I can’t wait for the day when we have something like this on Linux. There have been some attempts, but it’s not that easy. And it’s certainly not mainstream, yet.

I need to have a closer look at Linux’s Landlock soon (“soon”), but this is considerably more complicated than pledge()/unveil():

https://landlock.io/

“Learn Something Old Every Day, Part XV: KEYB Is Half of Keyboard BIOS”

https://www.os2museum.com/wp/learn-something-old-every-day-part-xv-keyb-is-half-of-keyboard-bios/

fn sub(foo: &String) {
    println!("We got this string: [{}]", foo);
}

fn main() {
    // "Hello", 0x00, 0x00, "!"
    let buf: [u8; 8] = [0x48, 0x65, 0x6C, 0x6C, 0x6F, 0x00, 0x00, 0x21];

    // Create a string from the byte array above, interpret as UTF-8, ignore decoding errors.
    let lossy_unicode = String::from_utf8_lossy(&buf).to_string();

    sub(&lossy_unicode);
}

Create a string from a byte array, but the result isn’t a string, it’s a cow 🐮, so you need another to_string() to convert your “string” into a string.

• https://doc.rust-lang.org/std/string/struct.String.html#method.from_utf8_lossy
  
• https://doc.rust-lang.org/std/borrow/enum.Cow.html
  

I still have a lot to learn.

(into_owned() instead of to_string() also works and makes more sense to me, it’s just that the compiler suggested to_string() first, which led to this funny example.)

@lyse@lyse.isobeef.org Rust is so different and, at the same time, so complex – it’s not far fetched to assume that I simply don’t understand what’s going on here. The docs appear to be clear, but alas … is it a bugs in the docs? Is it a lack of experience on my part? Who knows.

By the way, looks like there was a bit of a discussion regarding that name:

https://github.com/rust-lang/rust/issues/120048

So I was using this function in Rust:

https://doc.rust-lang.org/std/path/struct.Path.html#method.display

Note the little 1.0.0 in the top right corner, which means that this function has been “stable since Rust version 1.0.0”. We’re at 1.87 now, so we’re good.

Then I compiled my program on OpenBSD with Rust 1.86, i.e. just one version behind, but well ahead of 1.0.0.

The compiler said that I was using an unstable library feature.

Turns out, that function internally uses this:

https://doc.rust-lang.org/std/ffi/struct.OsStr.html#method.display

And that is only available since Rust 1.87.

How was I supposed to know this? 🤨🫩

@bender@twtxt.net Yeah, well, it’s a bit like twtxt. There is a Gopher community, but it’s small. I actually don’t like that HTTP is so easily accessible. I don’t like it that much when people post links to my site on HackerNews or something like that. Too much exposure.

Gopher is a small world. It’s slow and cozy.

And much like twtxt, the protocol is simple®, so it’s easier to tinker with it.

@prologic@twtxt.net Yeah, I’m very glad twtxt/Yarn doesn’t have this. ✌️

@kat@yarn.girlonthemoon.xyz Oh, ah, I didn’t even know they sold boxes. 🤯 I hope it still works!

@quark@ferengi.one It’s as close as coffee as you can get. 😅 They take the beans, apply magic, and then most of the caffeine is gone. You can also buy whole decaf’d beans and then grind them yourself. It does kill some of the flavor – but it’s not like you’re drinking black water.

@prologic@twtxt.net That isn’t really my strong suit. 😅

@thecanine@twtxt.net … all these stupid, pointless “apps” are stuff that I eventually have to remove from family devices … Sigh.

@bender@twtxt.net Both Gopher and Mastodon are a way for me to “babble”. 😅 I basically shut down Gopher in favor of Mastodon/Fedi last year. But the Fediverse doesn’t really work for me. It’s too focused on people (I prefer topics) and I dislike the addictive nature of likes and boosts (I’m not disciplined enough to ignore them). Self-hosting some Fedi thing is also out of the question (the minimalistic daemons don’t really support following hashtags, which is a must-have for me).

I’ll probably keep reading Fedi stuff, I just won’t post that much, I think.

Gopher server is back online and I’ll be phasing out Mastodon.

gopher://uninformativ.de

(No, I won’t do multi-protocol twtxt again. 😅)

@prologic@twtxt.net Yeah, it’s difficult, you often don’t get what you’d expect. They also make heavy use of 3rd party libraries. IIUC, for random numbers, they refer to this library. I’ve read many times that the Rust stdlib is intentionally minimalistic (to make it easier to maintain and port and all that).

I’m struggling with this, using 3rd party libs for so many things isn’t really my cup of tea. I’ll probably make my own tiny little “standard library”. It’s silly, but I don’t see any other options. 🤷

@bender@twtxt.net “Mhhhhhhh, hehehe, gonna poop on that car. 😏”

@lyse@lyse.isobeef.org That’s interesting, I see them (Teichrallen) everywhere I look. 🤯 It feels like they’re about as common as mallards (Stockenten) over here. 🤔