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martinjacobd

293 karma · joined June 25, 2011

embedded systems developer

https://github.com/martinjacobd

username[6:11] + username[0] + COMMON_EMAIL_SEPARATOR + username[6:11] + username[0:6] + "." + ORGANIZATION_TLD

martinjacobd.at.hn

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martinjacobd··on FBI arrests judge accused of helping man evade immigration authorities
If this complaint is true (my understanding is a complaint is always only one side of the story and the evidence presented may not end up being admissible, obviously IANAL and so forth), then seems quite similar to the MA case from several years ago: https://www.boston.com/news/local-news/2024/12/04/judge-shel...
martinjacobd··on Ancient switch to soft food gave us overbite–the ability to pronounce 'f's,'v'
Are you an endurance athlete?

I was surprised at how quickly my rhr came down after I started cycling more even though I've never been very active in my life.

It also (I think!) helped with my sleep apnea/general sleep problems, and I've always assumed a good bit of that was literally just being better at breathing.

martinjacobd··on Don't Get Distracted (2017)
Needs a [2017].

More substantively, my company is a contractor and has publicly committed to neither working on 'weapons' nor 'destructive financial systems.' Both terms are nebulous but we generally just decide en masse as a company (there are only 20 people) what does and doesn't count. I don't necessarily care for these particular lines in the sand but it's important to have some kind of process for determining and thinking about things, which I'm happy we do.

martinjacobd··on The messy quest to replace drugs with electricity
MIT grads get it for free.
martinjacobd··on I Know the secret to the quiet mind. I wish I'd never learned it (2021)
I've often felt this way about depression, but it's hard to tease apart the long-term after-effects of a depressive episode, the probability that my current symptoms might just be the beginnings of an episode, and the long-term (after-)effects of the medication I took/take for it.
martinjacobd··on "I Miss My Liver." Nonmedical Sources in the History of Hepatocentrism (2018)
meh the OED has this from early old English (albeit in the form of 'heortan') in the mid-tenth century from Bald's Leechbook.
martinjacobd··on Grindr Loses Almost Half Its Staff on 2-Day RTO Requirement
Yeah but you don't have to have either of those memberships and in big cities, at least, it's easy enough to get a hookup without them
martinjacobd··on Seven Sins of Writing
I can get behind this. Interesting that all three examples provided are improved by removing a "to be" verb. Reminds me of: https://en.wikipedia.org/wiki/E-Prime
martinjacobd··on Seven Sins of Writing
I guess I just don't see sentences like this, even from novice writers.
martinjacobd··on Seven Sins of Writing
touche :)
martinjacobd··on Seven Sins of Writing
That makes sense. I clearly didn't read the paratext closely enough :)
martinjacobd··on Seven Sins of Writing
I wish I understood what "wordiness" means. Perhaps it's restating the same simple point three times in as many loose sentences.

People who harp on this point usually point to the writing of Hemingway and similar writers (Carver comes to mind). All of these men are better writers than I am, but I still prefer to read Nabokov. Could Nabokov have "made his point" in fewer words? Almost certainly, but I wouldn't have enjoyed them any more.

martinjacobd··on No-more-secrets: recreate the decryption effect seen in the 1992 movie Sneakers
Embedded projects can be more complicated to build than the Linux kernel in two respects: Embedded projects are usually cross-compiled; whereas, one is ordinarily building the Linux kernel for that machine or one like it. And, hardware vendor code is usually bad.

I had one embedded project that I handrolled the makefile for, and it was all in pure C, no OS. That was fine, but ensuring that the versions of the hardware abstraction layer, and other drivers I wanted to use from the same vendor was a source of annoyance. Keeping track of which source files were to be enabled and disabled in the makefile was also annoying.

Another project I am working on uses platformio on an RTOS (and a much bigger micro). Platformio is written in Python to handle all of that 'seamlessly' and it does work pretty well from my perspective. And I don't have to manually install separate toolchains to /opt (or wherever) and keep track of them; it 'just works.'

I like the makefile approach. With only a little work, it's possible to make clean build directories without .o files littered around like mouse droppings. I know exactly what code is being built, and, because I usually have to write the linker script, where it is being put. But once it gets more complicated with different toolchains and compatibility problems (and it usually does if you have an RTOS), it sure is nice to have something like Platformio.

martinjacobd··on Io uring
Absolutely my pleasure. I tracked down the problem you commented about: I used a later version of liburing than ships with Ubuntu, so if you want to compile this as-is, you'll have to compile and install liburing from source probably. Glad you enjoyed it!
martinjacobd··on Io uring
I don't see why not. You'd open the socket on line 124 as a SOCK_DGRAM, 0 rather than what it is now for TCP. For an echo server, for instance, you wouldn't listen on the socket or accept requests; instead, you'd use io_uring_prep_recvmsg and use the prepended msghdr to send the identical packet back out with io_uring_prep_sendmsg.

At least, that's my untested understanding.

martinjacobd··on Io uring
I meant recv_multishot not multishot_accept. The one I linked does use multishot_accept. Just a think-o. Looks like your version uses both though, so that's cool.
martinjacobd··on Io uring
I recently tinkered around with io_uring for a presentation. Here is a toy echo server I made with it: https://gist.github.com/martinjacobd/be50a93744b94749339afe8... (non io_uring example for comparison: https://gist.github.com/martinjacobd/feea261d2fafe5e7332e37d...)

A big todo I have for this is to modify it to accept multishot_accept but I haven't been able to get a recent enough kernel configured properly to do it. (Only >6.0 kernels support multishot accept).

(edit) you need to s/multishot_accept/recv_multishot/g above :)

martinjacobd··on DM32 – a modern take on the HP-32SII calculator
I hope these people do something similar for the hp48 or 50 series, though I understand it's a big undertaking. I'd be the first person to buy it.
martinjacobd··on JPMorgan Chase and Co tracks employees to dystopian extents
There is the economy of scale problem you are talking about. There is just also a difference in culture. Many of the people at my work place are burned out from big tech jobs (or equally burned out from startup culture and want to work somewhere stable and established). I think they'd just leave if we implemented tracking. They are also unusually productive people who like the work they do. (At least it seems unusual from what I've heard about on here and elsewhere. I was self-employed before working here so unsure what is usual for wage earners.) Many of the people at my wife's workplace are hard-working but unenthusiastic and also tend to be older.
martinjacobd··on JPMorgan Chase and Co tracks employees to dystopian extents
> maybe because I'm not in the US? Or haven't spend much time at BigCorp?

My wife works at a BigCorp and I work at a small but established company. The differences in this arena couldn't be starker. I was given a laptop (and assembled my own desktop) and told to set it up according to my preferences first day. My wife has many metrics that she knows about tracked through her locked down MacBook (and I'm sure many more she doesn't know about). For my case I can't even think of how they'd track me while I work from home; for hers, she already knows that they do.

martinjacobd··on EPFL cancels Stallman's lecture citing “the situation regarding” his persona
csail-related really wasn't all that private. Anybody at MIT could add themselves to it (and perhaps could add others to it) and many undergraduates did just to see Stallman make the comments he did. (Long before this scandal, he had several amusing habits and mannerisms on this particular list.) It wasn't exactly public, but it wasn't really private either. And there had been prior scandals from it that had been made public ("a mailing list" in this article but I remember it happening on csail-related): https://thetech.com/2017/04/20/egg-donor-advert
martinjacobd··on IRS tests free e-filing system that could compete with tax prep giants
Meh it's rare, but the IRS does occasionally pay people interest. Usually it's of the "we were reviewing taxes and you overpaid by X amount so here is (1.03)^(years)×x." Still nonzero. Happened to me. https://www.irs.gov/payments/interest#pay
martinjacobd··on “Considered Harmful” Essays Considered Harmful (2002)
As even the OOP states, Dijikstra didn't choose this title, though. Niklaus Wirth did. From a different reference:

> Finally a short story for the record. In 1968, the Communications of the ACM published [...] "The goto statement considered harmful," which in later years would be most frequently referenced, regrettably, however, often by authors who had seen no more of it than its title, which became a cornerstone of my fame by becoming a template [....] But what had happened? I had submitted a paper under the title "A case against the goto statement," which in order to speed up its publication, the editor had changed into a "Letter to the Editor," and in the process he had given it a new title of his own invention! The editor was Niklaus Wirth.

https://www.cs.utexas.edu/users/EWD/ewd13xx/EWD1308.PDF (In Dijkstra's own, very beautiful print hand!)

martinjacobd··on On Having Enough Socks (2019)
Similarly, I've worn boat shoes or vans without socks since I was a freshman in high school and it's great! The only exceptions are dress shoes and when biking.
martinjacobd··on NYPD urges citizens to buy AirTags to fight surge in car thefts
How is the experience broken for anybody? I've been on group chats with my wife and parents (all iPhoners) for years and it's totally fine. I recently got a Pixel and now even the stupid emotes display properly (though it was easy to know what they meant before). I had an iphone forever ago (when my parents were paying for it), and I don't recall the experience of group chats being notably better or worse.

It's more annoying that I have three apps (signal, groupme, and discord) which each have a single friend or friend group that use them but that isn't an android/iphone problem.

martinjacobd··on Ask HN: Most interesting tech you built for just yourself?
This made my day, thank you for sharing. Such a sweet thing to do.
martinjacobd··on Will boiling water ruin green tea?
Don't the spores only matter for babies and the severely immunocompromised?
martinjacobd··on A colorful problem that has long frustrated mathematicians
Okay I see what you're saying. I was considering water as a hole in the map not a color, but that does make sense.
martinjacobd··on A colorful problem that has long frustrated mathematicians
> Michigan, with its separate upper peninsula, doesn’t actually prevent the U.S. map from being four-colorable, but it could, mathematically.

Couldn't you always "connect" the upper and lower parts of Michigan, four color the map that way, and then erase the line you drew? I'm having trouble seeing why Michigan (or Michigan-like states) could ever pose a problem as it seems to be solvable easily.

Does the hole caused by Lake Michigan pose a problem? I see the number of colors grows if you have a torus, but Lake Michigan (or its equivalent) is a 2D hole not a 3D one.

martinjacobd··on Boethius
My son's third name is Boethius! The Consolation of Philosophy is one of the best works I've ever read.
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