lock_acquire.html   [plain text]

<h2>lock_acquire</h2>
<hr>
<p>
<strong>Function</strong> - Acquire access rights to a lock.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   lock_acquire</strong>
                <strong>(lock_set_t</strong>                            <var>lock_set</var>,
                 <strong>int</strong>                                    <var>lock_id</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>lock_set</var>
<dd>
[in send right] The port naming the lock set which represents the
lock.
<p>
<dt> <var>lock_id</var>
<dd>
[in scalar] The lock, represented by the lock set, to be acquired.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>lock_acquire</strong> function acquires access rights to a specific lock
being represented by a given lock set. If the lock is already
controlled by another thread then the calling thread will block.
<h3>RETURN VALUES</h3>
<dl>
<p>
<dt> <strong>KERN_SUCCESS</strong>
<dd>
The lock was acquired.
<p>
<dt> <strong>KERN_INVALID_ARGUMENT</strong>
<dd>
The specified lock set is invalid, or the lock id is out of range.
<p>
<dt> <strong>KERN_LOCK_UNSTABLE</strong>
<dd>
The acquired lock has an unstable state.
     <p>
<dt> <strong>KERN_LOCK_SET_DESTROYED</strong>
<dd>
The specified lock has been destroyed.
<p>
<dt> <strong>KERN_ABORTED</strong>
<dd>
While blocked to wait for the specified lock to become available, the calling
     thread was awoken by an unrelated event, such as thread termination.
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="lock_release.html"><strong>lock_release</strong></a>,
<a href="lock_try.html"><strong>lock_try</strong></a>,
<a href="lock_handoff.html"><strong>lock_handoff</strong></a>,
<a href="lock_handoff_accept.html"><strong>lock_handoff_accept</strong></a>,
<a href="lock_make_stable.html"><strong>lock_make_stable</strong></a>,
<a href="lock_set_create.html"><strong>lock_set_create</strong></a>,
<a href="lock_set_destroy.html"><strong>lock_set_destroy</strong></a>.