@kat@yarn.girlonthemoon.xyz Pointers can be a bit tricky. I know it took me also quite some time to wrap my head around them. Let my try to explain. It’s a pretty simple, yet very powerful concept with many facets to it.

A pointer is an indirection. At a lower level, when you have some chunk of memory, you can have some actual values sitting in there, ready for direct use. A pointer, on the other hand, points to some other location where to look for the values one’s actually after. Following that pointer is also called dereferencing the pointer.

I can’t come up with a good real-world example, so this poor comparison has to do. It’s a bit like you have a book (the real value that is being pointed to) and an ISBN referencing that book (the pointer). So, instead of sending you all these many pages from that book, I could give you just a small tag containing the ISBN. With that small piece of information, you’re able to locate the book. Probably a copy of that book and that’s where this analogy falls apart.

In contrast to that flawed comparision, it’s actually the other way around. Many different pointers can point to the same value. But there are many books (values) and just one ISBN (pointer).

The pointer’s target might actually be another pointer. You typically then would follow both of them. There are no limits on how long your pointer chains can become.

One important property of pointers is that they can also point into nothingness, signalling a dead end. This is typically called a null pointer. Following such a null pointer calls for big trouble, it typically crashes your program. Hence, you must never follow any null pointer.

Pointers are important for example in linked lists, trees or graphs. Let’s look at a doubly linked list. One entry could be a triple consisting of (actual value, pointer to next entry, pointer to previous entry).

  _______________________
 /               ________\_______________
↓               ↓         |              \
+---+---+---+   +---+---+-|-+   +---+---+-|-+
| 7 | n | x |   | 23| n | p |   | 42| x | p |
+---+-|-+---+   +---+-|-+---+   +---+---+---+
      |         ↑     |         ↑
       \_______/       \_______/

The “x” indicates a null pointer. So, the first element of the doubly linked list with value 7 does not have any reference to a previous element. The same is true for the next element pointer in the last element with value 42.

In the middle element with value 23, both pointers to the next (labeled “n”) and previous (labeled “p”) elements are pointing to the respective elements.

You can also see that the middle element is pointed to by two pointers. By the “next” pointer in the first element and the “previous” pointer in the last element.

That’s it for now. There are heaps ;-) more things to tell about pointers. But it might help you a tiny bit.

@movq@www.uninformativ.de Hahaha, that name is certainly fitting! :-D

Yeah, I should revert that and try to figure out which programs misbehaved. But that’s something for future Lyse. 8-) Right now, I just redefine TERM in my Makefile when the USER happens to be me.

@lyse@lyse.isobeef.org There’s a reason it’s called “(n)curses”. 😏 The only advice I can give is to never fiddle with reassigning control sequences and $TERM variables. Leave $TERM at whatever value the terminal itself sets and use an appropriate terminfo file for it. If there are programs misbehaving, they probably blindly assume XTerm and should be fixed (or have XTerm as a hard requirement). If you try to fix this on your end, it’ll likely just break other programs. 🥴

Well, some time ago I put this in my ~/.Xdefaults:

URxvt.keysym.Control-Up:    \033[1;5A
    URxvt.keysym.Control-Down:  \033[1;5B
URxvt.keysym.Control-Left:  \033[1;5D
    URxvt.keysym.Control-Right: \033[1;5C

Probably to behave more like XTerm and fix a few other issues I had with other programs. But, it turns out, tcell expects the original sequence: https://github.com/gdamore/tcell/blob/main/terminfo/r/rxvt/term.go#L487

Hmm.

Java 24 released
Oracle, the company owned by a guy who purchased a huge chunk of the Kingdom of Hawaii from the Americans, has released Java 24. I’ll be honest and upfront: I just don’t care very much at all about this, as the only interaction I’ve had with Java over the past, I don’t know, 15 years or so, is either because of Minecraft, or because of my obsession with ancient UNIX workstations where Java programs pop up in the weirdest of places. I know Java is massive and used everywhere, but going through the … ⌘ Read more

i love everything pico.sh i wish i had more of a use for their services but the paste service is SUPER handy omg i finally had a reason to use it (to send a friend my unfinished failed marvel API bash program lol) and it’s epic. i love SSH i love TUI apps they are the best

spreadsheet program for terminal https://github.com/andmarti1424/sc-im

A more robust raw OpenBSD syscall demo
Ted Unangst published dude, where are your syscalls? on flak yesterday, with a neat demonstration of OpenBSD’s pinsyscall security feature, whereby only pre-registered addresses are allowed to make system calls. Whether it strengthens or weakens security is up for debate, but regardless it’s an interesting, low-level programming challenge. The original demo is fragile for multiple reasons, and requires manually locating and entering addresses for each bu … ⌘ Read more

NetBSD on a JavaStation
Back when Java was still a new programming language, Sun had the idea of building a computer specifically designed for Java, unique processor running byte-code as its native machine code and all. This whole endeavour proved to be more complicated than Sun had hoped, and as such, they eventually abandoned the idea of a Java processor in favour of plain SPARC. When the JavaStation shipped, it was a regular SPARC workstation without a hard drive, running something called JavaOS from fla … ⌘ Read more

C++ creator calls for help to defend programming language from ‘serious attacks’
Bjarne Stroustrup, creator of C++, has issued a call for the C++ community to defend the programming language, which has been shunned by cybersecurity agencies and technical experts in recent years for its memory safety shortcomings. C and C++ are built around manual memory management, which can result in memory safety errors, such as out of bounds reads and writes, though bo … ⌘ Read more

Short summary of Project2025 and Trump’s plans for the US:

• Abolish the Federal Reserve
  Why? To end what is seen as an unelected, centralized body that exerts too much influence over the economy and monetary policy, replacing it with a more transparent, market-driven approach.

• Implement a national consumption tax
  Why? To replace the current federal income tax system, simplify taxation, and increase government revenue through a broader base that includes all consumers.

• Lower corporate tax rates
  Why? To promote business growth, increase investment, and stimulate job creation by reducing the financial burden on companies.

• Deregulate environmental policies
  Why? To reduce government intervention in the economy, particularly in energy and natural resources sectors, and to foster a more business-friendly environment.

• Restrict abortion access
  Why? To align with conservative pro-life values and overturn or limit abortion rights, seeking to restrict the practice at a federal level.

• Dismantle LGBTQ+ protections
  Why? To roll back protections viewed as promoting LGBTQ+ rights in areas like employment and education, in line with traditional family values.

• Eliminate diversity, equity, and inclusion (DEI) programs
  Why? To end policies that are seen as divisive and to promote a merit-based system that prioritizes individual achievements over group identity.

• Enforce stricter immigration policies, including mass deportations and detentions
  Why? To prioritize border security, reduce illegal immigration, and enforce existing laws more aggressively, as part of a broader strategy to safeguard U.S. sovereignty.

• Eliminate the Department of Education
  Why? To reduce federal control over education and shift responsibilities back to local governments and private sectors, arguing that education decisions should be made closer to the community level.

• Restructure the Department of Justice
  Why? To ensure the department aligns more closely with the administration’s priorities, potentially reducing its scope or focus on areas like civil rights in favor of law-and-order policies.

• Appoint political loyalists to key federal positions
  Why? To ensure that government agencies are headed by individuals who are committed to advancing the administration’s policies, and to reduce the influence of career bureaucrats.

• Develop training programs for appointees to execute reforms effectively
  Why? To ensure that political appointees are equipped with the knowledge and skills necessary to implement the proposed changes quickly and effectively.

• Provide a 180-day transition plan with immediate executive orders
  Why? To ensure that the incoming administration can swiftly implement its agenda and make major changes early in its term without delay.

Do y’all agree with any/all/some of these poliices? Hmmm 🤔

#Project2025 #US #Trump

Does anybody know a right mouse click save and reduce a screen saver image to a smaller file, say 50KB?
My usual method is slow, place in image program and re-save it smaller.

I used to have a Window’s way to reduce file images from 1MB to 50 KB with right mouse click.

I finally got Ubuntu Software to find Kolourpaint and it installed, now when I run the APP nothing happens.
Dead, zip narda.

Stupid program , what is wrong?

Did the Windows 95 setup team forget that MS-DOS can do graphics?
One of the reactions to my discussion of why Windows 95 setup used three operating systems (and oh there were many) was my explanation that an MS-DOS based setup program would be text-mode. But c’mon, MS-DOS could do graphics! Are you just a bunch of morons? Yes, MS-DOS could do graphics, in the sense that it didn’t actively prevent you from doing graphics. You were still responsible for everything you … ⌘ Read more

JotaleaOS: a very tiny hobby operating system
JotaleaOS is an open source, minimalistic, experimental operating system made by Jotalea, designed for extreme low-resource environments. It does not support external programs or games, as it lacks a standard application execution environment. The system is entirely self-contained, running only its built-in commands. ↫ JotaleaOS website Exactly what is says on the tin: a tiny operating system created entirely as a learning experience. That’s … ⌘ Read more

that’s a fair point.

Perhaps, since Twitter in 2006 never implemented read flags, every derivative microblogging system never saw that as an expected feature. This is curious because Twitter started with SMS, where on our phones we can mark messages as read or unread.
I think it all comes from the difference between reading an email (directed to you) vs. reading public posts (like a blog or a ‘wall,’ where you don’t mark posts as read). It’s not necessary to mark it as ‘read’, you just jump over it.

Reading microblogging posts in an email program is not common, I think, and I haven’t really used it, so I cannot say how it works, and whether it would be better for me or not.
However, I’ve used Thunderbird as a feed reader, and I understand the advantages when reading blog posts.

About read flags being simple, well… we just had a discussion this morning about how tracking read messages would require a lot of rethinking for clients such as timeline where no state is stored. Even considering some kind of ‘notification of unread messages or mentions’ is not expected for those minimalist client, so it’s an interesting compromise to think about.

@eapl.me@eapl.me Read flags are so simple, yet powerful in my opinion. I really don’t understand why this is not a thing in most twtxt clients. It’s completely natural in e-mail programs and feed readers, but it hasn’t made the jump over to this domain.

Well, that’s another bug: The search https://twtxt.net/search?q=%22LOOOOL%2C+great+programming+tutorial+music%22 yields the wrong hash. It should have been poyndha instead.

cli/q: 🌱 A simple programming language. - q - Projects I really like this little q lang that Ed has created ❤️ Really nice and simpler, great design and implementation and really lovely cross-platform compiler supporting DOS, Windows, Darwin and Linux on AMD64 and ARM64 💪

Android 16’s Linux Terminal will soon let you run graphical apps, so of course we ran Doom
Regardless, the fact that Android’s Linux Terminal can run graphical apps like Doom now is good news. Hopefully we’ll be able to run more complex desktop-class Linux programs in the future. I tried running GIMP, for example, but it didn’t work. Eventually, Android should be able to run Linux apps as well as Chromebooks can, as I believe one of the goals … ⌘ Read more

Google begins requiring JavaScript for Google Search
Google says it has begun requiring users to turn on JavaScript, the widely used programming language to make web pages interactive, in order to use Google Search. In an email to TechCrunch, a company spokesperson claimed that the change is intended to “better protect” Google Search against malicious activity, such as bots and spam, and to improve the overall Google Search experience for users. The spokesperson noted that, with … ⌘ Read more

Google Begins Requiring JavaScript For Google Search
Google says it has begun requiring users to turn on JavaScript, the widely-used programming language to make web pages interactive, in order to use Google Search. From a report: In an email to TechCrunch, a company spokesperson claimed that the change is intended to “better protect” Google Search against malicious activity, such as bots and spam, and to improve the over … ⌘ Read more

Alright, I have a little 8086 assembler for my toy OS going now – or rather a proof-of-concept thereof. It only supports a tiny fraction of the instruction set. It was an interesting learning experience, but I don’t think trying to “complete” this program is worth my time.

The whole thing is just a learning project, I don’t want to actually make a usable OS. There are a few more things I want to have a look at and then I’ll eventually move on to 386/amd64 later this year (hopefully).

https://movq.de/v/d8f30cbe75/vid3.mp4

@kat@yarn.girlonthemoon.xyz To improve you shell programming skills, I highly recommend to check out shellcheck: https://github.com/koalaman/shellcheck It points out common errors and gives some suggestions on how to improve the code. Some details in shell scripting are very tricky to get right at first. Even after decades of shell programming, I run into “corner cases” every now and then.

E.g. in getlyr’s line 7 it warns:

echo -e $(gum style --italic --foreground "#f4b8e4" "'$artist', '$song'")
        ^-- SC2046: Quote this to prevent word splitting.

For more information:
  https://www.shellcheck.net/wiki/SC2046 -- Quote this to prevent word splitt...

Most likely not all that problematic in this application, but it’s good to know about this underlying concept. Word splitting is basically splitting tokens on whitespace, this can lead to interesting consequences as illustrated by this little code:

$ echo $(echo "Hello   World")
Hello World

$ echo "$(echo "Hello   World")" 
Hello   World

In the first case the shells sees two whitespace-separated tokens or arguments for the echo command. This basically becomes echo Hello World. So, echo joins them by a single space. In the second one it sees one argument for the echo command, so echo simply echos this single argument that contains three spaces.

Chess Zoo
⌘ Read more

The editor can launch a new shell now:

https://movq.de/v/6ec68b50dd/los86-edit-shell.mp4

Trivial to implement but super useful. It allows for simple but meaningful dev cycles: Edit source code, run/test it, back to editor. That’s what I do in the video.

(The Brainfuck program is silly, but I got nothing else at the moment.)

The I/O cache is also getting better. All that back and forth doesn’t hit the disk at all, once cached.

This whole thing is much more fun and interesting when you run it from a real floppy disk. It’s a 5.25” floppy in the video (so it’s actually floppy 😅). Disk seek times can be catastrophic and you don’t notice any of this on modern disks.

@movq@www.uninformativ.de Woohoo, noice! Now you can ship, even sell it! :-D

All kidding aside, even though I never wrote a proper brainfuck program myself, I do like that. :-) Keep it going.

My OS has a Brainfuck interpreter now and this counts as a programming language, right? We’re feature complete now. 😂

https://movq.de/v/1335167b35/vid4.mp4

rose put crack in apt because jesus christ i just find myself mindlessly chanting “apateu apateu” under my breath at the most random times. some brain programming shit

@movq@www.uninformativ.de woah it’s like a cheatsheet with explanations! java is kind of arcane magic sorcery to me so i’m having trouble understanding it but i have that with most programming languages. this is like so much easier to actually look at and read instead of my eyes glazing over lol

@movq@www.uninformativ.de That’s so damn cool mate! I went through the code, but this lowlevel stuff is really not my favorite cup of tea. Having said that, it was actually really nice to see the abstractions and APIs work together and how things are getting indeed very readable in the userland programs. That’s easy to track in this extremely tiny OS implementation. Excellent work, keep on hacking!

Now, you just have to quickly add a network stack and then can write a twtxt client for it! ]:->

@prologic@twtxt.net oh it’s ok! thank you for the explanation! i think for me when it comes to programming i learn best by doing, so like written examples or talking about it helps less, BUT baseline explanations like what a pointer is does help! i was so confused and i still need to fix the error i’m having but i will figure it out!

@movq@www.uninformativ.de Wow, quite an elaborate editor you’ve programmed there!

Okay, this is pretty cool. My 8086 toy OS running on my old Pentium from an actual floppy disk. 😍 I just love that sound and the feeling of using floppies. This brings back so many memories from my early DOS days.

The cp-unopt program copies a file and intentionally uses small unaligned reads/writes (hopefully triggers more bugs).

The I/O cache works “okay-ish”, I guess. When sha1 runs, it has to do a few reads for the first file and basically none for the second one. Both could have been served entirely from the cache, theoretically. (But even just having an I/O cache in the first place speeds up things dramatically.)

Notice how there’s an EA file. That’s a left-over from OS/2, because I copied some files to the floppy using OS/2. In other words, my FAT12 implementation survives OS/2 writing to it. 🥳 (But I guess it should show up as EA DATA.SF. My current code starts at the left and stops at the first space.)

https://movq.de/v/d4d50d3c74/los86-on-p133-from-floppy-small2.mp4

Thanks @bender@twtxt.net for the feedback. I fixed and expanded the article. I’m sorry for my poor interaction. Furthermore, I’m reading and writing while programming a client in Emacs.

Sunset:

Image

No, of course not. This is the gingerbread in the oven with my digicam’s sunset program. The second photo shows the colors more like they are in reality. It surprises me every year how absolutely sticky this dough is. Holy cow! Close to impossible to spread it evenly in the baking tray. https://lyse.isobeef.org/tmp/lebkuchen-2024-12-20/

@eapl.me@eapl.me @bender@twtxt.net @skinshafi@thunix.net The feed that nobody follows out of fear.

When I started programming in Delphi, I always included all the files (not only the *.exe, but also *.pas and what else there was) when giving friends my programs on floppy disks. I didn’t know that the executable was technically enough. :-)

@aelaraji@aelaraji.com This is an Intel i7-3770 from 2013 with an integrated GPU (HD 4000).

Looks like FreeCAD works fine and I think this is a more appropriate program anyway. 😊

If I use Fedora on my PC, Vivaldi as my browser, Signal as my main messenger program, then which OS should my phone run on?

LOOOOL, great programming tutorial music: https://www.youtube.com/watch?v=yup8gIXxWDU

a new emmanation of my trusty old vim config, now available as a home-manager nix module. now i can track my dependencies with nix instead of using git subtree and it makes installing backend programs like language servers and such way easier. https://src.ix.cyb.red/pe-vim/

Its time to brush up on your competitive programming skills!

https://cses.fi/book/book.pdf

Image

stick computers, to snugly fit in reclaimed plastic tubes/containers #halfbaked #coding #programming #embedded #electronics

today I wrote a CV sequencer in VoodooAssembly for work O__O #coding #programming #embedded

#fzf is the new emacs: a tool with a simple purpose that has evolved to include an #email client. https://sr.ht/~rakoo/omail/

I’m being a little silly, of course. fzf doesn’t actually check your email, but it appears to be basically the whole user interface for that mail program, with #mblaze wrangling the emails.

I’ve been thinking about how I handle my email, and am tempted to make something similar. (When I originally saw this linked the author was presenting it as an example tweaked to their own needs, encouraging people to make their own.)

This approach could surely also be combined with #jenny, taking the place of (neo)mutt. For example mblaze’s mthread tool presents a threaded discussion with indentation.

@prologic@twtxt.net Brute force. I just hashed a bunch of versions of both tweets until I found a collision.

I mostly just wanted an excuse to write the program. I don’t know how I feel about actually using super-long hashes; could make the twts annoying to read if you prefer to view them untransformed.

when I say ‘functional programming’ you think ‘haskell’ and I think ‘BQN’

Image

OK I found this one, small enough, but where does it install to? can’t find the app, of any files of anything.
Being a total novice to Linux stuff….where is this file located and why don’t they prompt you for a folder location of the program? And why such a stupid name? Dozens to choose from and most over 300MB, not what I want - I just want Apache to run the index.html webpage or the index.php webpage. I do not need Javascript or Java programming editors….

If some of you budding fathers want to know how I created a computer nerd to one day work for Facebook in the big USA, well you purchase a $1000 Xmas present, an enormous thick book with C++ programming, and say, you can play as many games as you like kids, but James has to create them using computer software.

SO James created once a 3D chess program with sound, took 6 months or so, really hard to beat, not based on logic moves point by point like other chess programs, this one was based on the depth of looking for patterns, set it to 5 moves ahead and you were toast every time. Nice program too, sadly gone over the years, computers suffer from bit rot. We used to try and mark rotten hard drive discs once as bad sectors, not sure how UBuntu does this these days, I see a dozen errors on the screen every time I load.

Today I would purchase for my kids AI CAD simulation software with metal 3D printer and get your child to build fancy 3D models and engines from scratch. This will make them an expert in the CAD AI industry by the time they are 14 years old. Sadly AI is here to stay and will spoil the Internet.

@bender@twtxt.net Is it so maxed out you couldn’t fit a pretty small program like Headscale on it? Headscale by itself and only personal home type use as far as amount of peers go, it really isn’t noticeable I don’t think resource-wise. The Docker version I guess could be a different story.