defend from -> :() { :&:; } ;:

Bill Moran wmoran at
Mon Oct 22 15:25:23 PDT 2007

In response to Martin Tournoij <carpetsmoker at>:

> On Sun 21 Oct 2007 12:10, Danielisz Laszlo wrote:
> > Please do not try to execute this: :() { :&:; } ;: on your BSD machine.
> > I ask all who already tried it how to defend from this?
> Wow,, my machine just crashed :-/
> Does in this work on other OS's as well (ie. GNU/Linux)? Or just
> (Free?)BSD? I really don't feel like crashing another machine right
> now...

It's a fork bomb.  It affects every OS that has fork() or equivalent.

> Only works in sh, not in csh.

No, it works in csh, the syntax is different.

> Anyway, this seems to be security/stability issue, maybe a PR is in
> order?

No.  Research (on your point) into fork bombs and how to configure
the system to handle them properly is in order.

Bill Moran

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