Dangerous Terminal Commands

[Captain Awesome]

I was surprised to not find one of these threads here. Thought I might as well start one. Here is a list of commands you should NEVER run in Terminal unless you're sure what you are doing. There are fake tutorials around that will try and get you to run these:

DO NOT PASTE THESE COMMANDS IN TERMINAL.

1) Erase everything on hard drive with no warning:

rm -rf /

rm -rf *

2) Erase everything in Home folder with no warning:

rm -rf ~/

3) Instantly format current drive:

mkfs.(anything)

4) Forkbomb. Will keep executing processes until the system freezes:

:(){:|:&};:

fork while fork

5) Open every application in /Applications at once:

open /Applications/*

Feel free to add to the list.

 

[Darth.Titan]

People who blindly execute Terminal commands without knowing what they mean deserve what they get.

Most of those will also need a `sudo` to be the most harmful BTW

 

[techfreak85]

will do nothing with out being root or Sudo. and i herd somewhere, but i have no clue the validity, that Apple changed the OS so you couldn't do

Sudo rm -rf /

dont wanna try it

 

[okrelayer]

this worries me. because, i am one of the people that will search the internet and find something that will "open all safari windows in tabs" or whatnot, and blindly paste the info into terminal. Although, i do try to stick to trusted mac hint/tip websites

 

[TuffLuffJimmy]

this worries me. because, i am one of the people that will search the internet and find something that will "open all safari windows in tabs" or whatnot, and blindly paste the info into terminal. Although, i do try to stick to trusted mac hint/tip websites

Don't do that then. Make sure you can read what a command is doing before you use it. For the most part though defaults write can't do much harm.

 

[sammich]

Awesome, I was looking for this baby (although I'd like the look of the one with foo instead)

){:|:&};:

Apparently you need to run it for as many cores to really test it out? or was that the yes > null command?

 

[TuffLuffJimmy]

The fork bombs don't actually hurt your system though do they? won't they just crash the computer and a restart will fix everything?

 

[sammich]

The fork bombs don't actually hurt your system though do they? won't they just crash the computer and a restart will fix everything?

Yeah, it basically a bottomless tree of threads. But it crashes your computer o so efficiently.

EDIT: or not...all I get is a pile of "-bash: fork: Resource temporarily unavailable" and nothing.

 

[TuffLuffJimmy]

Yeah, it basically a bottomless tree of threads. But it crashes your computer o so efficiently.

EDIT: or not...all I get is a pile of "-bash: fork: Resource temporarily unavailable" and nothing.

Same. Neither of those did anything for me, although I really didn't expect "fork while forking" to do anything.

 

[sammich]

Same. Neither of those did anything for me, although I really didn't expect "fork while forking" to do anything.

There's some interesting reading up at http://en.wikipedia.org/wiki/Fork_bomb.

for while fork is perl, which may run in terminal without extras but I can't remember how.

 

[mslide]

While this is a nice idea, there are tons of "dangerous" unix commands. People who don't understand what they are doing shouldn't be playing around in terminal. Get a book about unix basics and read man pages. Even if someone here gives them a command to run (like I've done before), they should take the time to learn each and every part of it so they fully understand what it does.

BTW, I like the fork bomb one.

 

[serytjbfxgnkies]

Yeah, it basically a bottomless tree of threads. But it crashes your computer o so efficiently.

EDIT: or not...all I get is a pile of "-bash: fork: Resource temporarily unavailable" and nothing.

lolololol this is what im looking for

I will definately run some of these on my friends computer

 

[Mikael H]

I will definately run some of these on my friends computer

@Captain Awesome: Above quote is exactly why these threads aren't around...

I'll reiterate what has already been said: Don't execute terminal commands without a rudimentary understanding of what they do. Any half-decent search engine will help you there.
And whatever you do: If you play around with things that might cause data loss, keep backups of your data.

 

[old-wiz]

Fooling around with *NIX commands without knowing exactly what happens is a recipe for disaster. When I was working we would have newbies who supposedly had CS degrees and were "fluent" with whatever *NIX and they would learn the hard way. It was kind of fun giving them a polite lecture on how not to wreck the system. Fortunately we always had multiple incremental backups offline so nothing was really damaged.