One of those functions that isn't really implementable in standard C, requiring either compiler support, or being written in straight Assembly for stack registers manipulation, one of those "micro runtime" features for C.
From UNIX 7th edition all the way up to C99, when VLAs where introduced, only to be made optional in C11, and the C23 update still doesn't support automatic VLAs, only for function parameters, thus the point stands.
I wonder how Linux manages without explicit _chkstk? In my experience, it feels like MAP_GROWSDOWN regions have way more than 1 guard page below its start — I can poke like a megabyte lower than its start, and the kernel will grow the memory region into there just fine.
One thing that scares me a little is whether there are younger developers, say, 25-40, who can and want to pick up the mantle of Windows internals gurus.
I mean, Chen has decades of winternals in his head. Microsoft has been gutting their staff for years now. When the Petzold/Chen generation hang up their spurs, does Microsoft still have a critical mass of people who understand Windows from the metal up?
> One thing that scares me a little is whether there are younger developers, say, 25-40, who can and want to pick up the mantle of Windows internals gurus.
A similar "brain drain" has occurred in macOS (formerly known as OS-X) over the years, as evident in man page documentation for "newer" daemons shipped. An easy way to verify this is to run:
It was never OS-X, it was OS X, and originally Mac OS X, as in the one after Mac OS 9. The Mac prefix was dropped with Lion (10.7). The Mac OS lingo having itself been introduced with 7.6, before that the OS core was called System.
Why do you think Windows is currently such a mess?
Microsoft new blood has been educated on Macs and ChromeOS, even if they do games it is most likely consoles.
On WinUI community calls you usually would get puzzled faces when the Q&A touched when would WinUI be able to do "insert basic Win32/Forms/WPF" feature.
Management apparently doesn't care they actually understand Windows, or get the required trainings to meet the quality of their predecessors.
i fear the times when the chip makers change their architectures and the OS makers have to change the inner working of their OSes but then again, I guess there is an equivalent in the chip-making industry as well
It’s fun to understand just for intellectual curiosity’s sake but the number of people who get to work on shipping code where ring-0 knowledge is useful has to be minuscule as a percentage. It feels like a minor miracle I got to work on device drivers in my career. I imagine students might be more worried about completing assignments and good grades than the ins and outs of debuggers, too, though understanding those is important for problems one is more likely to come across in work projects versus smaller school assignments.
> the number of people who get to work on shipping code where ring-0 knowledge is useful has to be minuscule as a percentage
I wonder if it it is more that the percentage of people who choose to dedicate themselves to that type of work is miniscule. I work in graphics and performance, and it seems similar.
Few people really work on it specifically at any given company, and I've heard people warn others that there are few jobs in it.
But video game companies really want people for those roles and will pay well because they're hard to find. Still, few programmers show any interest in specializing in those skills. If you're passionate about it and willing to learn the details you'll eventually find a lot of job opportunities. I know people who want to work with this and do so - I know many more who have specifically said they want to stay away from it. I don't know anyone who wants to and can't.
Before listing resources, let me state that the single most important thing is to learn by doing. Write a lot of rendering code, experiment a lot with your own ideas and variations on each exercise. Once you move past the basics don't be afraid to spend several evenings in a row failing to fix what in hindsight seems like an embarrassingly simple math error. That is how you go from having read and sort of understood something to really knowing it. Also, the best approach is usually to devour as much content as you can from several sources to get a wider perspective.
There are a lot of great resources out there. The best modern beginner friendly resource I am aware of is Scratchapixel[0]. Back when I was first learning 3D I used to follow tutorials on places like NeHe Productions[1], which is probably a bit dated these days.
For more comprehensive information on all kinds of techniques, with examples from big games for each technique, the absolutely best resource is the book Real-Time Rendering[2].
If you're interested in ray-tracing rather than rasterization (i.e. more film than video games) a lot of people recommend "Ray Tracing in One Weekend"[3]. If you want to learn state of the art ray-tracing in depth, with all the math and and theory, the best resource is "Physically Based Rendering: From Theory to Implementation"[4], which is freely available online.
Arguably the lower level abstractions are more interesting too! how exactly Windows does ring-0 is less interesting than writing your own ring-0! And unless you care about writing driver-level software for Windows or contributing to the kernel, learning this is also less useful.
I'm essentially arguing that unless you work at MSFT, there's next to no reason to learn that specific abstraction layer.
One trend to watch is AI cheat devices. Instead of running detectable software they have a fully separate device that uses AI for object detection and aimbotting. If cheaters move to using those, then the argument for kernel mode anticheat weakens. And that is the cornerstone keeping gamers on windows.
Now I'm looking forward to these AI cheat devices. It's going to be hilarious if the kernel anticheat malware finally gets killed by AI aimbots of all things.
While I’m not sure if this is a bot (where did vidya enter the convo?), game hacking on both cheat and anticheat side has genuinely deep Windows internals knowledge (admittedly somewhat lopsided, but deep nonetheless)
Producer and consumer sides are tied. If there is strong demand for windows development then there will be money sloshing around which will attract devs. I predict demand will decrease, at least for this particular niche.
To go even further off topic, being called a bot is certainly a wake up call for me that the internet is dying, and I'm not ready for it, and need to reposition myself asap somehow.
This is great. I'm learning Rust myself and your son's article contributed to my knowledge.
I'm also very impressed by part 2. I have my own lisp but I haven't managed to implement a compiler or code generation yet. Really enjoyed reading about the hashmap too. The textbook solution to collisions is probing and comparison. It never occurred to me that I could just resize the underlying array until the collisions disappear altogether.
One of those functions that isn't really implementable in standard C, requiring either compiler support, or being written in straight Assembly for stack registers manipulation, one of those "micro runtime" features for C.
From UNIX 7th edition all the way up to C99, when VLAs where introduced, only to be made optional in C11, and the C23 update still doesn't support automatic VLAs, only for function parameters, thus the point stands.
Recommended related reading: https://nullprogram.com/blog/2024/02/05/
Related to the above, two important concepts to know w.r.t a stack are "Red Zone" and "Guard Pages".
Raymond Chen again;
Why do we even need to define a red zone? Can’t I just use my stack for anything? - https://devblogs.microsoft.com/oldnewthing/20190111-00/?p=10...
A closer look at the stack guard page - https://devblogs.microsoft.com/oldnewthing/20220203-00/?p=10...
I wonder how Linux manages without explicit _chkstk? In my experience, it feels like MAP_GROWSDOWN regions have way more than 1 guard page below its start — I can poke like a megabyte lower than its start, and the kernel will grow the memory region into there just fine.
It doesn't. This causes the StackClash vulnerability.
One thing that scares me a little is whether there are younger developers, say, 25-40, who can and want to pick up the mantle of Windows internals gurus.
I mean, Chen has decades of winternals in his head. Microsoft has been gutting their staff for years now. When the Petzold/Chen generation hang up their spurs, does Microsoft still have a critical mass of people who understand Windows from the metal up?
> One thing that scares me a little is whether there are younger developers, say, 25-40, who can and want to pick up the mantle of Windows internals gurus.
A similar "brain drain" has occurred in macOS (formerly known as OS-X) over the years, as evident in man page documentation for "newer" daemons shipped. An easy way to verify this is to run:
And compare the man pages for the daemons running with the man page for `launchd`.While this exercise is illuminating, it is also depressing IMHO.
> formerly known as OS-X
It was never OS-X, it was OS X, and originally Mac OS X, as in the one after Mac OS 9. The Mac prefix was dropped with Lion (10.7). The Mac OS lingo having itself been introduced with 7.6, before that the OS core was called System.
And the documentation, now it is mostly generated, the famous Apple books are now gone, at least the archive is still available.
Why do you think Windows is currently such a mess?
Microsoft new blood has been educated on Macs and ChromeOS, even if they do games it is most likely consoles.
On WinUI community calls you usually would get puzzled faces when the Q&A touched when would WinUI be able to do "insert basic Win32/Forms/WPF" feature.
Management apparently doesn't care they actually understand Windows, or get the required trainings to meet the quality of their predecessors.
That is how you get Webview2 all over the place.
i fear the times when the chip makers change their architectures and the OS makers have to change the inner working of their OSes but then again, I guess there is an equivalent in the chip-making industry as well
I was a dev on the Visual Studio and Windows teams in the 90s. I’m retired but mentor CS students at two local universities.
I haven’t had a student in two years that was even remotely interested in ring-0, internals, or really understanding a debugger.
I’m not being critical; they are just focused on higher level abstractions.
It’s fun to understand just for intellectual curiosity’s sake but the number of people who get to work on shipping code where ring-0 knowledge is useful has to be minuscule as a percentage. It feels like a minor miracle I got to work on device drivers in my career. I imagine students might be more worried about completing assignments and good grades than the ins and outs of debuggers, too, though understanding those is important for problems one is more likely to come across in work projects versus smaller school assignments.
> the number of people who get to work on shipping code where ring-0 knowledge is useful has to be minuscule as a percentage
I wonder if it it is more that the percentage of people who choose to dedicate themselves to that type of work is miniscule. I work in graphics and performance, and it seems similar.
Few people really work on it specifically at any given company, and I've heard people warn others that there are few jobs in it.
But video game companies really want people for those roles and will pay well because they're hard to find. Still, few programmers show any interest in specializing in those skills. If you're passionate about it and willing to learn the details you'll eventually find a lot of job opportunities. I know people who want to work with this and do so - I know many more who have specifically said they want to stay away from it. I don't know anyone who wants to and can't.
How would one start learning about it?
Before listing resources, let me state that the single most important thing is to learn by doing. Write a lot of rendering code, experiment a lot with your own ideas and variations on each exercise. Once you move past the basics don't be afraid to spend several evenings in a row failing to fix what in hindsight seems like an embarrassingly simple math error. That is how you go from having read and sort of understood something to really knowing it. Also, the best approach is usually to devour as much content as you can from several sources to get a wider perspective.
There are a lot of great resources out there. The best modern beginner friendly resource I am aware of is Scratchapixel[0]. Back when I was first learning 3D I used to follow tutorials on places like NeHe Productions[1], which is probably a bit dated these days.
For more comprehensive information on all kinds of techniques, with examples from big games for each technique, the absolutely best resource is the book Real-Time Rendering[2].
If you're interested in ray-tracing rather than rasterization (i.e. more film than video games) a lot of people recommend "Ray Tracing in One Weekend"[3]. If you want to learn state of the art ray-tracing in depth, with all the math and and theory, the best resource is "Physically Based Rendering: From Theory to Implementation"[4], which is freely available online.
[0] https://www.scratchapixel.com/
[1] https://nehe.gamedev.net/
[2] https://www.realtimerendering.com/
[3] https://raytracing.github.io/
[4] https://www.pbrt.org/
Arguably the lower level abstractions are more interesting too! how exactly Windows does ring-0 is less interesting than writing your own ring-0! And unless you care about writing driver-level software for Windows or contributing to the kernel, learning this is also less useful.
I'm essentially arguing that unless you work at MSFT, there's next to no reason to learn that specific abstraction layer.
Speaking of debuggers...
I still twitch whenever someone says "use ddd" and they are not referring to Evans' seminal work.
:-D
> who can
Probably enough to keep Windows going, at least.
> and want to
Not if the pay or location is uncompetitive.
Why do you think that is not already happening within Microsoft?
Maybe they'll just train Copilot on their code to help them.
One trend to watch is AI cheat devices. Instead of running detectable software they have a fully separate device that uses AI for object detection and aimbotting. If cheaters move to using those, then the argument for kernel mode anticheat weakens. And that is the cornerstone keeping gamers on windows.
Now I'm looking forward to these AI cheat devices. It's going to be hilarious if the kernel anticheat malware finally gets killed by AI aimbots of all things.
While I’m not sure if this is a bot (where did vidya enter the convo?), game hacking on both cheat and anticheat side has genuinely deep Windows internals knowledge (admittedly somewhat lopsided, but deep nonetheless)
Producer and consumer sides are tied. If there is strong demand for windows development then there will be money sloshing around which will attract devs. I predict demand will decrease, at least for this particular niche.
To go even further off topic, being called a bot is certainly a wake up call for me that the internet is dying, and I'm not ready for it, and need to reposition myself asap somehow.
Obviously it's Copilot /s
Only passingly related, some fun rust stack-allocation insanity by my 17yo son:
https://ogghostjelly.github.io/slog/alloca.html
This is great. I'm learning Rust myself and your son's article contributed to my knowledge.
I'm also very impressed by part 2. I have my own lisp but I haven't managed to implement a compiler or code generation yet. Really enjoyed reading about the hashmap too. The textbook solution to collisions is probing and comparison. It never occurred to me that I could just resize the underlying array until the collisions disappear altogether.
17? You should be very proud. This is good work for anyone, but especially at his age!
Very impressive for a 17yo!