osfmk/man/lock_acquire.html

   1 <h2>lock_acquire</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Acquire access rights to a lock.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   lock_acquire</strong>
   8                 <strong>(lock_set_t</strong>                            <var>lock_set</var>,
   9                  <strong>int</strong>                                    <var>lock_id</var><strong>);</strong>
  10 </pre>
  11 <h3>PARAMETERS</h3>
  12 <dl>
  13 <p>
  14 <dt> <var>lock_set</var>
  15 <dd>
  16 [in send right] The port naming the lock set which represents the
  17 lock.
  18 <p>
  19 <dt> <var>lock_id</var>
  20 <dd>
  21 [in scalar] The lock, represented by the lock set, to be acquired.
  22 </dl>
  23 <h3>DESCRIPTION</h3>
  24 <p>
  25 The <strong>lock_acquire</strong> function acquires access rights to a specific lock
  26 being represented by a given lock set. If the lock is already
  27 controlled by another thread then the calling thread will block.
  28 <h3>RETURN VALUES</h3>
  29 <dl>
  30 <p>
  31 <dt> <strong>KERN_SUCCESS</strong>
  32 <dd>
  33 The lock was acquired.
  34 <p>
  35 <dt> <strong>KERN_INVALID_ARGUMENT</strong>
  36 <dd>
  37 The specified lock set is invalid, or the lock id is out of range.
  38 <p>
  39 <dt> <strong>KERN_LOCK_UNSTABLE</strong>
  40 <dd>
  41 The acquired lock has an unstable state.
  42      <p>
  43 <dt> <strong>KERN_LOCK_SET_DESTROYED</strong>
  44 <dd>
  45 The specified lock has been destroyed.
  46 <p>
  47 <dt> <strong>KERN_ABORTED</strong>
  48 <dd>
  49 While blocked to wait for the specified lock to become available, the calling
  50      thread was awoken by an unrelated event, such as thread termination.
  51 </dl>
  52 <h3>RELATED INFORMATION</h3>
  53 <p>
  54 Functions:
  55 <a href="lock_release.html"><strong>lock_release</strong></a>,
  56 <a href="lock_try.html"><strong>lock_try</strong></a>,
  57 <a href="lock_handoff.html"><strong>lock_handoff</strong></a>,
  58 <a href="lock_handoff_accept.html"><strong>lock_handoff_accept</strong></a>,
  59 <a href="lock_make_stable.html"><strong>lock_make_stable</strong></a>,
  60 <a href="lock_set_create.html"><strong>lock_set_create</strong></a>,
  61 <a href="lock_set_destroy.html"><strong>lock_set_destroy</strong></a>.