Rule for Beginners

Wugmeister@lemmy.dbzer0.com to 196@lemmy.blahaj.zone – 642 points –

cross-posted from: https://lemmy.dbzer0.com/post/14479799

Linux Best Practices

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Every time this gets reposted, I like to reply with this:

:(){:|:&};:

Run it if you dare lol

I don't know what that is, but it feels to me like it might be a fork bomb.

Edit: Yep, fork bomb.

Because I didn't know what a fork bomb was:

a fork bomb is a denial-of-service (DoS) attack wherein a process continually replicates itself to deplete available system resources, slowing down or crashing the system due to resource starvation.

[...]

A classic example of a fork bomb is one written in Unix shell :(){ :|:& };:, possibly dating back to 1999, which can be more easily understood as

fork() { fork | fork & } fork

> 
> In it, a function is defined (fork()) as calling itself (fork), then piping (|) its result into itself, all in a background job (&).
> 
> The code using a colon `:` as the function name is not valid in a shell as defined by POSIX, which only permits alphanumeric characters and underscores in function names. However, its usage is allowed in GNU Bash as an extension.

[Wikipedia](https://en.wikipedia.org/wiki/Fork_bomb)

You're telling markdown to format the code in the language fork() { and then break the code block early by not having > in front of the next line. Here's a quoted code block formatted in sh:

fork() {
   fork | fork &
}
fork

It seems the app I use to browse doesn't play entirely nice with markdown. I updated my formatting a little, thanks for the notice.