What are Linux Devices !?

[@Ozzymand]

"So you don't have to struggle as much as I did" 🗣🗣🗣🗣 my man spitting generational fire here

[@MohidoTech]

@@Ozzymand I am not that old, come on 😅

[@Ozzymand]

@@MohidoTech Never said you were! Just complimenting your dedication to helping the people!

[@MohidoTech]

@@OzzymandI know brother, was just kiddin 😅. I truly appreciate your kind words, I really do. thank you.

[@moussaadem7933]

devices communicate through input/output. this make them analogus to files. "Everything is a file" is a great abstraction. linux does this a lot. devices and files are just files. processes and threads are just tasks. directories and filenames are just paths (that's why mv renames and moves)

[@MohidoTech]

I honestly love how Linux kernel work! Once you understand the Linux kernel, you start getting what a computer is and how it really works!

[@someoneunknown6894]

Great video! Would love to learn more about the network devices!

[@MohidoTech]

I will create that one soon :)

[@tannguyen_91]

I appreciate your work here

[@savagesarethebest7251]

I find it really intuitive, like do you want some user input? Just open Standard Input. Want to write something, open standard output. Do you want a file from the network, just open it. Do you want a stream of coordinates from GPS or the trackpad, just open the file. This is especially good if your program operates on standard input and output, then it can be used in ways that you have never imagined decades after you made it.

[@MohidoTech]

Exactly, I totally agree in that sense. This abstraction makes it easier for both, driver implementer and applications/kernel communication!

[@Momoyon]

Yes, would love more videos like this! You earned a sub

[@MohidoTech]

@@Momoyon Thanks! And you will get what you love ;)

[@gryzus2475]

Drivers are not a strict subset of all modules. Most drivers can also be built into the kernel directly and they will not be listed by the lsmod command. I will give you the benefit of the doubt though, they might still technically be modules but of the type "builtin" - check yourself with this command: less /lib/modules/`uname -r`/modules.builtin Another thing, the /dev/random may not require _specific_ hardware but it requires _some_ hardware to function, more precisely, it requires the entropy the hardware produces to generate cryptographically strong random bytes. Not sure whether modern Linux kernel versions block (6.6+) if there is not enough entropy to seed the random number generator, but the point is that you have to obtain these initial random bytes from the hardware (it is not strictly kernel functionality). Not a nit at all, I think you meant to convey the same thing, how succinctly at that! Great video.

[@MohidoTech]

@@gryzus2475 these are very valuable insights!

[@le24_qr6nod]

Would love to watch more such videos 🗣️🔥

[@arijeetsarkar1512]

Thank you ❤

[@MohidoTech]

Great to hear that you enjoyed it

[@willabytes]

Appreciated!

[@urebeatsgaming7285]

Very informative. Really liked the logical device part, always wondered what things like /dev/null were doing

[@MohidoTech]

I am more than happy that it helped you!

[@pabloqp7929]

Really enjoyed this video, cheers!

[@elidoz9522]

the part about the network devices sounds interesting, it sounds like it goes against the unix philosophy

[@MohidoTech]

IKR! At first, it does seem odd, but it makes sense when you consider the complexity of networking devices compared to USBs or hard drives. "Linux sticks to 'Everything is a File' but takes a unique approach for networking. Tricks like this are what make tech fun"- *said by a non-'implentist' 😅* Since many people asked❤, the next video is about: Linux networking. I will start working on it tomorrow and hopefully I publish it asap 😄 NOTE Implentist (noun created by Mohido): Someone who unfairly discriminates against or holds biases toward certain implementations of a concept, system, or technology, often based on personal preference or traditional norms. 🤣🤣🤣

[@NguyễnLong-o1t]

Thank you very much

[@RasyaAnindyaPratama-m9r]

great content bro!

[@MohidoTech]

That means a lot, thank you man!🙃

[@susugar3338]

"Everything is a file" helps me understand Linux very much. But I always find funny when i get return "rm: dir is a folder, not a file."

[@MohidoTech]

@@susugar3338 In the past, even 'cat' worked on folders.. It was pretty wild backthen lol

[@ytnihad]

great video. thank you.

[@MohidoTech]

Don’t mention it!

[@DanielNerd]

great video! i'd love to see a video about how linux handle the network devices, always wondered why they weren't on /dev/ like everything else, but never actually spent the time to check.

[@MohidoTech]

The networking topic is huge to cover to be honest in a single ~5mins video. I just released a video providing a brief overview... kzbin.info/www/bejne/f2mUfWWNh7KWsKM However, I will create another video to explain the details on how it really works from inside the Linux kernel, explaining the kernel Network stack and other stuff. Probably even virtual interfaces.

[@DanielNerd]

@@MohidoTech nice! will go watch it right now!

[@muhammadowais2492]

you can treat anything like a file in Linux, Want to check how much memory your system is using? cat /proc/meminfo Want to see what processes are running? cat /proc/cpuinfo Want to change your hardware's settings? Just open /dev/ like it's a folder of random files, and hope you don't break anything.😅

[@muhammadowais2492]

Appreciate your this video, hope it'll be helpful for young ones

[@MohidoTech]

@@muhammadowais2492 thank you man for your support! It really means a lot!

[@MartinWoad]

A lot of the time you will not be allowed to write to these files. The fact that they are files is simply an abstraction, an illusion presented to you by the kernel. Remember also that handling files is often slow and introduces overhead. It is fun for the simplicity of it, but things are simple in userland because they are complicated undernearth in the kernel. And this complexity introduces overhead. So always consider if you can use other IPC mechanism instead if you are looking to be performant and often times there is no reason not to.

[@MohidoTech]

@@MartinWoad Exactly, take GPU for onstance, it exists in the /dev/ but really can only be used through System Calls.

[@justgold1]

Channel will get big

[@MohidoTech]

@@justgold1 Thousand thanks man! Ur words r just gold!! Even if it doesnt go big, I am doing these vids coz I luv it 😅

[@MartinWoad]

I don't quite understand why non-essential drivers are handled as kernel modules. From my perspetice, they should be handled as userland daemons that can be easily turned and off and installed whenever needed. If they need to be in the kernel due to performance overhead then they should be patched later optionally. Adding more and more bloat to the kernel, especially if its mainline, increases the attack surface and decreases the stability of the system. The mainline kernel should only contain things that are absolutely essential.

[@MohidoTech]

TBH, great question! Well, while kernel modules DO add code to the kernel, they're actually separate from the core kernel code and can be loaded/unloaded dynamically using commands like modprobe. The reason drivers need to be kernel modules rather than userland processes is that they need direct access to hardware and must operate at the kernel's privilege level. The kernel's primary job is to safely manage hardware access and provide a consistent interface to userspace programs. Moving drivers to userspace would break this security and abstraction model, as it would require giving userspace programs direct hardware access. I hope this answer provides a better insight on why and how kernel is a middle-man between applications (userland) and hardware (driversland).

[@SingularCherubim]

This is actually how printers and scanners are handled (CUPS and SANE, respectively): there's a single kernel module that calls out to userland drivers. FUSE is the same thing for filesystems, but you can't use userland drivers (or even dynamic modules) for boot devices.

[@MohidoTech]

@@SingularCherubim This is something new to me. Thank you for sharing this information 🙏

[@nonetrix3066]

What opened my eye to everything being a file a lot is /dev/amdkfd when I was trying to debug AI related issues on my AMD GPU, I assume ROCm and Vulkan compute just cats stuff there and it just werks somehow

[@MohidoTech]

That is possible especially that the `/dev/dri/card0` is used by the graphics-drivers to do some stuff. But not actually used by the application directly

[@justgold1]

Yes bro 🔥🔥🔥🔥☄️☄️☄️

[@0xPanda1]

Great video

[@MohidoTech]

@@0xPanda1 thank you man! I truly appreciate your words. I will try to make the next one even better!

[@rinatpro-q1r]

linux devices is files

[@MohidoTech]

@@rinatpro-q1r exactly, it is weird and fun to think that way. That's why linux-ers love linux.. It's always fun 😆

[@dasten123]

so devices actually are **not** files, they just appear as files in /dev?? That's wild, so "everything is a file" is a total lie...

[@MohidoTech]

@@dasten123 They lied to us.. when I started using linux I thought using: 'touch /dev/mouse' will create an actual new mouse into existence ;P😫

[@MohidoTech]

@@dasten123 But asside from me joking, yeah.. you are correct in that sense. It is the way the kernel developers decided to abstract simple devices.. So the applications can just use a simple file operation instead of a complex system call.

[@qwerte6948]

i mean it is obvius right? not everything is a file but that doesnt mean you couldnt use it as such

[@dzwassim95]

German?

[@MohidoTech]

@@dzwassim95 nope, y the question tho?

[@dzwassim95]

@@MohidoTech feels like german accent

[@MohidoTech]

@@dzwassim95 lmao 🤣 Well, sorry to disappoint u 😅

[@Cloud67TR]

sudo mount /dev/sda1 /mnt

[@MohidoTech]

@Cloud67TR 'sudo mount /usr/Cloud67TR /comments' 😁

[@Solving_Engineer]

Great video

[@MohidoTech]

Thank you, I hope I helped you with simplifying the idea :)