+<h2>vm_wire</h2>
+<hr>
+<p>
+<strong>Function</strong> - Modify the target region's paging characteristics.
+<h3>SYNOPSIS</h3>
+<pre>
+<strong>kern_return_t vm_wire</strong>
+ <strong>(host_priv_t</strong> <var>host</var>,
+ <strong>vm_task_t</strong> <var>target_task</var>,
+ <strong>vm_address_t</strong> <var>address</var>,
+ <strong>vm_size_t</strong> <var>size</var>,
+ <strong>vm_prot_t</strong> <var>wired_access</var><strong>);</strong>
+</pre>
+<h3>PARAMETERS</h3>
+<dl>
+<p>
+<dt> <var>host</var>
+<dd>
+[in host-control send right]
+The control port for the host for which
+information is to be obtained.
+<p>
+<dt> <var>target_task</var>
+<dd>
+[in task send right]
+The port for the task whose address space contains
+the region.
+<p>
+<dt> <var>address</var>
+<dd>
+[in scalar]
+The starting address for the region.
+<p>
+<dt> <var>size</var>
+<dd>
+[in scalar]
+The number of bytes in the region.
+<p>
+<dt> <var>wired_access</var>
+<dd>
+[in scalar]
+The pageability of the region. The following values cause
+the region to be wired and protected as specified
+(values may be combined):
+<dl>
+<dt> <strong>VM_PROT_READ</strong>
+<dt> <strong>VM_PROT_WRITE</strong>
+<dt> <strong>VM_PROT_execute</strong>
+</dl>
+<p>
+The following value causes the region to be unwired (made pageable):
+<dl>
+<dt> <strong>VM_PROT_NONE</strong>
+</dl>
+</dl>
+<h3>DESCRIPTION</h3>
+<p>
+The <strong>vm_wire</strong> function sets the pageability privileges
+for a region within the
+specified task's address space. <var>wired_access</var> specifies the types
+of accesses to
+the memory region which must not suffer from (internal) faults
+of any kind after
+this call returns. A non-null <var>wired_access</var> value indicates that
+the page is to be
+"wired" into memory; a null value indicates "un-wiring". The kernel maintains
+for the region a count of the number of times the region is wired. A page is
+wired into physical memory if any task accessing it has a non-zero wired count
+for the page.
+<p>
+The region starts at the beginning of the virtual page containing
+<var>address</var>; it ends at the end of the virtual page containing
+<var>address</var> + <var>size</var> - 1. Because of this
+rounding to virtual page boundaries, the amount of memory affected may be
+greater than <var>size</var>. Use <strong>host_page_size</strong> to find the current
+virtual page size.
+<h3>NOTES</h3>
+<p>
+This interface is machine word length specific because of the virtual address
+parameter.
+<h3>RETURN VALUES</h3>
+<dl>
+<p>
+<dt> <strong>KERN_INVALID_ADDRESS</strong>
+<dd>
+The address is illegal or specifies a non-allocated region.
+</dl>
+<h3>RELATED INFORMATION</h3>
+<p>
+Functions:
+<a href="thread_wire.html"><strong>thread_wire</strong></a>.