linuxmemes

21355 readers

1322 users here now

Hint: :q!

Sister communities:

Community rules (click to expand)

1. Follow the site-wide rules

Instance-wide TOS: https://legal.lemmy.world/tos/
Lemmy code of conduct: https://join-lemmy.org/docs/code_of_conduct.html

2. Be civil

Understand the difference between a joke and an insult.

Do not harrass or attack members of the community for any reason.

Leave remarks of "peasantry" to the PCMR community. If you dislike an OS/service/application, attack the thing you dislike, not the individuals who use it. Some people may not have a choice.

Bigotry will not be tolerated.

These rules are somewhat loosened when the subject is a public figure. Still, do not attack their person or incite harrassment.

3. Post Linux-related content

Including Unix and BSD.

Non-Linux content is acceptable as long as it makes a reference to Linux. For example, the poorly made mockery of sudo in Windows.

No porn. Even if you watch it on a Linux machine.

4. No recent reposts

Everybody uses Arch btw, can't quit Vim, and wants to interject for a moment. You can stop now.

Please report posts and comments that break these rules!

Important: never execute code or follow advice that you don't understand or can't verify, especially here. The word of the day is credibility. This is a meme community -- even the most helpful comments might just be shitposts that can damage your system. Be aware, be smart, don't fork-bomb your computer.

founded 1 year ago

MODERATORS

[email protected]

348

Theoretical physicists: Actually... (sh.itjust.works)

submitted 1 month ago by [email protected] to c/[email protected]

32 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 15 points 1 month ago (3 children)

Programmatically, what does the kernel actually do with data sent to /dev/null? Put it in a temp buffer and just delete it?

[–] [email protected] 20 points 1 month ago (1 children)

I was also curious, here's a good answer:

https://unix.stackexchange.com/questions/670199/how-is-dev-null-implemented

The implementation is:

static ssize_t write_null(struct file *file, const char __user *buf,
              size_t count, loff_t *ppos)
{
    return count;
}

[–] [email protected] 16 points 1 month ago (1 children)

So it's basically doing nothing and lying about it. 😆

[–] [email protected] 17 points 1 month ago (1 children)

"I accepted all of the bytes you gave me. I didn't do anything with them, but I accept you gave them to me".

[–] [email protected] 4 points 1 month ago (1 children)

Could've at least say thank you...

[–] [email protected] 2 points 1 month ago (1 children)

It's open source. If manners are an important feature to you perhaps look into contributing... :)

[–] [email protected] 2 points 1 month ago

Yeah, that could actually be fun to be honest, lol 😂. But I just know the PR would be rejected, lol 😂.

[–] [email protected] 17 points 1 month ago

The syscall to write passes a buffer and length. If it is Dev null the call just returns without doing anything more.

[–] [email protected] 6 points 1 month ago* (last edited 1 month ago)

Programmatically, what does the kernel actually do with data sent to /dev/null?

I imagine it's like getting nullified in that olde show ReBoot.