osfmk/man/vm_copy.html

   1 <h2>vm_copy</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Copy a region of virtual memory.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   vm_copy</strong>
   8                 <strong>(vm_task_t</strong>            <var>target_task</var>,
   9                  <strong>vm_address_t</strong>      <var>source_address</var>,
  10                  <strong>vm_size_t</strong>                  <var>count</var>,
  11                  <strong>vm_address_t</strong>        <var>dest_address</var><strong>);</strong>
  12 </pre>
  13 <h3>PARAMETERS</h3>
  14 <dl>
  15 <p>
  16 <dt> <var>target_task</var>
  17 <dd>
  18 [in task send right]
  19 The port for the task whose memory is to be copied.
  20 <p>
  21 <dt> <var>source_address</var>
  22 <dd>
  23 [in scalar]
  24 The starting address for the source region.  The address must
  25 be on a page boundary.
  26 <p>
  27 <dt> <var>count</var>
  28 <dd>
  29 [in scalar]
  30 The number of bytes in the source region.  The number of
  31 bytes must convert to an integral number of virtual pages.
  32 <p>
  33 <dt> <var>dest_address</var>
  34 <dd>
  35 [in scalar]
  36 The starting address for the destination region.  The address
  37 must be on a page boundary.
  38 </dl>
  39 <h3>DESCRIPTION</h3>
  40 <p>
  41 The <strong>vm_copy</strong> function copies a source region to a destination
  42 region within the
  43 same task's virtual memory.  It is semantically equivalent to
  44 <strong>vm_read</strong> followed
  45 by <strong>vm_write</strong>.  The destination region can overlap the source region.
  46 <p>
  47 The destination region must already be allocated.  The source region must be
  48 readable, and the destination region must be writable.
  49 <h3>NOTES</h3>
  50 <p>
  51 This interface is machine word length specific because of the virtual address
  52 parameter.
  53 <h3>RETURN VALUES</h3>
  54 <dl>
  55 <p>
  56 <dt> <strong>KERN_PROTECTION_FAILURE</strong>
  57 <dd>
  58 The source region is protected against reading, or the destination
  59 region is protected against writing.
  60 <p>
  61 <dt> <strong>KERN_INVALID_ADDRESS</strong>
  62 <dd>
  63 An address is illegal or specifies a non-allocated region, or there is not
  64 enough memory following one of the addresses.
  65 </dl>
  66 <h3>RELATED INFORMATION</h3>
  67 <p>
  68 Functions:
  69 <a href="vm_protect.html"><strong>vm_protect</strong></a>,
  70 <a href="vm_read.html"><strong>vm_read</strong></a>,
  71 <a href="vm_write.html"><strong>vm_write</strong></a>,
  72 <a href="host_page_size.html"><strong>host_page_size</strong></a>.