osfmk/man/mach_port_get_refs.html

   1 <h2>mach_port_get_refs</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Return the current count of user references on the target port right.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   mach_port_get_refs</strong>
   8                 <strong>(ipc_space_t</strong>                               <var>task</var>,
   9                  <strong>mach_port_name_t</strong>                          <var>name</var>,
  10                  <strong>mach_port_right_t</strong>                        <var>right</var>,
  11                  <strong>mach_port_urefs_t</strong>                        <var>*refs</var><strong>);</strong>
  12 </pre>
  13 <h3>PARAMETERS</h3>
  14 <dl>
  15 <p>
  16 <dt> <var>task</var>
  17 <dd>
  18 [in task send right]
  19 The task holding the right.
  20 <p>
  21 <dt> <var>name</var>
  22 <dd>
  23 [in scalar]
  24 The task's name for the right.
  25 <p>
  26 <dt> <var>right</var>
  27 <dd>
  28 [in scalar]
  29 The type of right/entity being examined:
  30 <dl>
  31 <p>
  32 <dt> <dd>
  33 <strong>MACH_PORT_RIGHT_SEND</strong>
  34 <p>
  35 <dt> <dd>
  36 <strong>MACH_PORT_RIGHT_RECEIVE</strong>
  37 <p>
  38 <dt> <dd>
  39 <strong>MACH_PORT_RIGHT_SEND_ONCE</strong>
  40 <p>
  41 <dt> <dd>
  42 <strong>MACH_PORT_RIGHT_PORT_SET</strong>
  43 <p>
  44 <dt> <dd>
  45 <strong>MACH_PORT_RIGHT_DEAD_NAME</strong>
  46 </dl>
  47 <p>
  48 <dt> <var>refs</var>
  49 <dd>
  50 [out scalar]
  51 Number of user references.
  52 </dl>
  53 <h3>DESCRIPTION</h3>
  54 <p>
  55 The <strong>mach_port_get_refs</strong> function returns the number
  56 of user references a task
  57 has for a right.
  58 <p>
  59 If <var>name</var> denotes a right, but not the type of right specified,
  60 then zero is returned.
  61 Otherwise a positive number of user references is returned.  Note a name may
  62 simultaneously denote send and receive rights.  The number of references for
  63 send-once rights is always one.
  64 <h3>NOTES</h3>
  65 <p>
  66 This interface is machine word length specific because of the port name
  67 parameter.
  68 <h3>RETURN VALUES</h3>
  69 <dl>
  70 <p>
  71 <dt> <strong>KERN_INVALID_NAME</strong>
  72 <dd>
  73 <var>name</var> did not denote a right.
  74 </dl>
  75 <h3>RELATED INFORMATION</h3>
  76 <p>
  77 Functions:
  78 <a href="mach_port_mod_refs.html"><strong>mach_port_mod_refs</strong></a>.