This is xnu-10002.1.13. See this file in:
<h2>processor_set_default</h2>
<hr>
<p>
<strong>Function</strong> - Return the default processor set.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t	processor_set_default</strong>
		<strong>(host_t</strong>	<var>host</var>,
		<strong>processor_set_name_t</strong>	<var>default_set_name</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<dt> <var>host</var> 
<dd>
[in host-name send right]
The name (or control) port for the host for 
which the default processor set is desired.
<dt> <var>default_set_name</var> 
<dd>
[out processor-set-name send right]
The returned name port for the
default processor set.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>processor_set_default</strong> function returns the name
port for the default
processor set for the specified host.  The default processor
set is used by all threads, 
tasks and processors that are not explicitly assigned to other sets.
<h3>RETURN VALUES</h3>
<p>
Only generic errors apply.
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="processor_set_info.html">processor_set_info</a>,
<a href="thread_assign.html">thread_assign</a>,
<a href="task_assign.html">task_assign</a>.