osfmk/man/mach_port_deallocate.html

   1 <h2>mach_port_deallocate</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Decrement the target port right's user reference count.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   mach_port_deallocate</strong>
   8                 <strong>(ipc_space_t</strong>                               <var>task</var>,
   9                  <strong>mach_port_name_t</strong>                          <var>name</var><strong>);</strong>
  10 </pre>
  11 <h3>PARAMETERS</h3>
  12 <dl>
  13 <p>
  14 <dt> <var>task</var>
  15 <dd>
  16 [in task send right]
  17 The task holding the right.
  18 <p>
  19 <dt> <var>name</var>
  20 <dd>
  21 [in scalar]
  22 The task's name for the right.
  23 </dl>
  24 <h3>DESCRIPTION</h3>
  25 <p>
  26 The <strong>mach_port_deallocate</strong> function releases a user reference
  27 for a right.  It is
  28 an alternate form of <strong>mach_port_mod_refs</strong> that allows
  29 a task to release a user
  30 reference for a send or send-once right without failing if the
  31 port has died and
  32 the right is now actually a dead name.
  33 <p>
  34 If <var>name</var> denotes a dead name, send right, or send-once right,
  35 then the right loses
  36 one user reference.  If it only had one user reference, then
  37 the right is destroyed.
  38 If <var>name</var> does not denote an element in the port name space, the
  39 function returns
  40 success.
  41 <h3>NOTES</h3>
  42 <p>
  43 This interface is machine word length specific because of the port name
  44 parameter.
  45 <h3>RETURN VALUES</h3>
  46 <dl>
  47 <p>
  48 <dt> <strong>KERN_INVALID_RIGHT</strong>
  49 <dd>
  50 The <var>name</var> parameter denoted an invalid right.
  51 </dl>
  52 <h3>RELATED INFORMATION</h3>
  53 <p>
  54 Functions:
  55 <a href="mach_port_allocate.html"><strong>mach_port_allocate</strong></a>,
  56 <a href="mach_port_allocate_name.html"><strong>mach_port_allocate_name</strong></a>,
  57 <a href="mach_port_mod_refs.html"><strong>mach_port_mod_refs</strong></a>.