os161 / man / testbin / forkbomb.html
forkbomb.html
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<html>
<head>
<title>forkbomb</title>
<body bgcolor=#ffffff>
<h2 align=center>forkbomb</h2>
<h4 align=center>OS/161 Reference Manual</h4>

<h3>Name</h3>
<p>
forkbomb - create hundreds of processes
</p>

<h3>Synopsis</h3>
<p>
<tt>/testbin/forkbomb</tt>
</p>

<h3>Description</h3>
<p>
<tt>forkbomb</tt> does
<pre>
   while (1) fork();
</pre>
doing a bit of additional checking similar to that done by
<A HREF=forktest.html>forktest</A>.
</p>

</p>
<strong>
DO NOT RUN THIS ON A REAL SYSTEM - IT WILL GRIND TO A HALT AND
PEOPLE WILL COME AFTER YOU WIELDING BASEBALL BATS AND/OR THE AD
BOARD<sup><font size=-1>*</font></sup>. WE WARNED YOU.
</strong>
</p>

<p>
<font size=-1><i><sup>*</sup> The Administrative Board of Harvard
College handles formal disciplinary action.</i></font>
</p>

<h3>Requirements</h3>
<p>
<tt>forkbomb</tt> uses the following system calls:
<ul>
<li> <A HREF=../syscall/fork.html>fork</A>
<li> <A HREF=../syscall/getpid.html>getpid</A>
<li> <A HREF=../syscall/write.html>write</A>
<li> <A HREF=../syscall/_exit.html>_exit</A>
</ul>
</p>

<p>
We don't expect your system to withstand this without grinding to
a halt, but once your basic system calls are complete it shouldn't
crash. Likewise for after your virtual memory system is complete.
</p>

<p>
Note that this may turn out to be hard to achieve in practice. Don't
spend much time fixing problems <tt>forkbomb</tt> triggers that won't
arise under more normal operation. (If in doubt, consult your course
staff.)
</p>

</body>
</html>