xnu-1504.15.3.tar.gz

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<h2>memory_object_destroy</h2>
<hr>
<p>
<strong>Function</strong> - Shut down a memory object.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   memory_object_destroy</strong>
                <strong>(memory_object_control_t</strong>         <var>memory_control</var>,
                 <strong>kern_return_t</strong>                           <var>reason</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>memory_control</var> 
<dd>
[in memory-cache-control send right]
The memory cache control port 
to be used by the memory manager for cache management requests. 
This port is provided by the kernel in a <strong>memory_object_init</strong> call.
<p>
<dt> <var>reason</var> 
<dd>
[in scalar]
An error code indicating when the object must be destroyed.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>memory_object_destroy</strong> function tells the kernel to shut down the
specified memory object.  As a result of this call, the kernel
no longer supports
paging activity or any memory object calls on the memory object.
The kernel issues 
a <strong>memory_object_terminate</strong> call to pass to the memory
manager all rights to 
the memory object port and the memory control port.
<p>
To ensure that any modified cached data is returned before the object is
terminated, the memory manager should call <strong>memory_object_lock_request</strong>
with
<var>should_flush</var> set and a 
lock value of <strong>VM_PROT_WRITE</strong> before it makes the 
<strong>memory_object_destroy</strong> call.
<h3>NOTES</h3>
<p>
The <var>reason</var> code is currently ignored by the kernel.
<h3>RETURN VALUES</h3>
<p>
Only generic errors apply.
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="memory_object_lock_request.html"><strong>memory_object_lock_request</strong></a>,
<a href="memory_object_terminate.html"><strong>memory_object_terminate</strong></a>.