-<h2>memory_object_data_error</h2>
\r<hr>
\r<p>
\r<strong>Function</strong> - An error prevents the supply of previously requested data.
\r<h3>SYNOPSIS</h3>
\r<pre>
\r<strong>kern_return_t memory_object_data_error</strong>
\r <strong>(memory_object_control_t</strong> <var>memory_control</var>,
\r <strong>vm_offset_t</strong> <var>offset</var>,
\r <strong>vm_size_t</strong> <var>size</var>,
\r <strong>kern_return_t</strong> <var>reason</var><strong>);</strong>
\r</pre>
\r<h3>PARAMETERS</h3>
\r<dl>
\r<p>
\r<dt> <var>memory_control</var>
\r<dd>
\r[in memory-cache-control send right]
\rThe memory cache control port
\rto be used by the memory manager for cache management requests.
\rThis port is provided by the kernel in a <strong>memory_object_create</strong> call.
\r<p>
\r<dt> <var>offset</var>
\r<dd>
\r[in scalar]
\rThe offset within the memory object, in bytes.
\r<p>
\r<dt> <var>size</var>
\r<dd>
\r[in scalar]
\rThe number of bytes of data (starting at <var>offset</var>). The number
\rmust convert to an integral number of memory object pages.
\r<p>
\r<dt> <var>reason</var>
\r<dd>
\r[in scalar]
\rReason for the error.
\r</dl>
\r<h3>DESCRIPTION</h3>
\r<p>
\rThe <strong>memory_object_data_error</strong> function indicates that
\rthe memory manager
\rcannot provide the kernel with the data requested for the given region,
\rspecifying a reason for the error.
\r<p>
\rWhen the kernel issues a <strong>memory_object_data_request</strong> call, the memory
\rmanager can respond with a <strong>memory_object_data_error</strong>
\rcall to indicate that the
\rpage cannot be retrieved, and that a memory failure exception should be raised
\rin any client threads that are waiting for the page. Clients
\rare permitted to catch
\rthese exceptions and retry their page faults. As a result, this
\rcall can be used to
\rreport transient errors as well as permanent ones. A memory manager can use
\rthis call for both hardware errors (for example, disk failures) and software
\rerrors (for example, accessing data that does not exist or is protected).
\r<h3>NOTES</h3>
\r<p>
\rIf reason has a system code of <var>err_kern</var>, the kernel will substitute
\ran error value
\rof <strong>KERN_MEMORY_ERROR</strong>.
\r<h3>RETURN VALUES</h3>
\r<p>
\rOnly generic errors apply.
\r<h3>RELATED INFORMATION</h3>
\r<p>
\rFunctions:
\r<a href="memory_object_data_request.html"><strong>memory_object_data_request</strong></a>,
\r<a href="memory_object_data_supply.html"><strong>memory_object_data_supply</strong></a>,
\r<a href="MO_data_unavailable.html"><strong>memory_object_data_unavailable</strong></a>.
\r\ No newline at end of file
+<h2>memory_object_data_error</h2>
+<hr>
+<p>
+<strong>Function</strong> - An error prevents the supply of previously requested data.
+<h3>SYNOPSIS</h3>
+<pre>
+<strong>kern_return_t memory_object_data_error</strong>
+ <strong>(memory_object_control_t</strong> <var>memory_control</var>,
+ <strong>vm_offset_t</strong> <var>offset</var>,
+ <strong>vm_size_t</strong> <var>size</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_create</strong> call.
+<p>
+<dt> <var>offset</var>
+<dd>
+[in scalar]
+The offset within the memory object, in bytes.
+<p>
+<dt> <var>size</var>
+<dd>
+[in scalar]
+The number of bytes of data (starting at <var>offset</var>). The number
+must convert to an integral number of memory object pages.
+<p>
+<dt> <var>reason</var>
+<dd>
+[in scalar]
+Reason for the error.
+</dl>
+<h3>DESCRIPTION</h3>
+<p>
+The <strong>memory_object_data_error</strong> function indicates that
+the memory manager
+cannot provide the kernel with the data requested for the given region,
+specifying a reason for the error.
+<p>
+When the kernel issues a <strong>memory_object_data_request</strong> call, the memory
+manager can respond with a <strong>memory_object_data_error</strong>
+call to indicate that the
+page cannot be retrieved, and that a memory failure exception should be raised
+in any client threads that are waiting for the page. Clients
+are permitted to catch
+these exceptions and retry their page faults. As a result, this
+call can be used to
+report transient errors as well as permanent ones. A memory manager can use
+this call for both hardware errors (for example, disk failures) and software
+errors (for example, accessing data that does not exist or is protected).
+<h3>NOTES</h3>
+<p>
+If reason has a system code of <var>err_kern</var>, the kernel will substitute
+an error value
+of <strong>KERN_MEMORY_ERROR</strong>.
+<h3>RETURN VALUES</h3>
+<p>
+Only generic errors apply.
+<h3>RELATED INFORMATION</h3>
+<p>
+Functions:
+<a href="memory_object_data_request.html"><strong>memory_object_data_request</strong></a>,
+<a href="memory_object_data_supply.html"><strong>memory_object_data_supply</strong></a>,
+<a href="MO_data_unavailable.html"><strong>memory_object_data_unavailable</strong></a>.
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