xnu-1504.3.12.tar.gz

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<h2>lock_set_create</h2>
<hr>
<p>
<strong>Function</strong> - Create a new lock set.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   lock_set_create</strong>
                <strong>(task_t</strong>                                    <var>task</var>,
                 <strong>lock_set_t</strong>                            <var>lock_set</var>,
                 <strong>int</strong>                                      <var>locks</var>,
                 <strong>int</strong>                                     <var>policy</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>task</var>
<dd>
The task receiving the send right to the newly created lock set.
<p>
<dt> <var>lock_set</var>
<dd>
[out send right] The port naming the lock set which represents the lock.
<p>
<dt> <var>locks</var>
<dd>
[in scalar] The number of locks the lock set will represent (must be a positive value).
<p>
<dt> <var>policy</var>
<dd>
[in scalar] The blocked thread wakeup policy for the newly created lock set. Valid policies are:
     <dl>
<p>
<dt> SYNC_POLICY_FIFO
<dd>
a first-in-first-out policy for scheduling thread wakeup.
<p>
<dt> SYNC_POLICY_FIXED_PRIORITY
<dd>
a fixed priority policy for scheduling thread wakeup.
</dl>
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>lock_set_create</strong> function creates a new lock set representing a
collection of associated locks. The lock set is associated with the
specified task. A send right naming the lock set is returned to the
caller.
<h3>RETURN VALUES</h3>
<dl>
<p>
<dt> <strong>KERN_SUCCESS</strong>
<dd>
The lock set was created.
<p>
<dt> <strong>KERN_INVALID_ARGUMENT</strong>
<dd>
Either the task or policy argument is invalid, or the locks argument
has a value that is less than or equal to zero.
<p>
<dt> <strong>KERN_RESOURCE_SHORTAGE</strong>
<dd>
The kernel could not allocate the lock set.
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="lock_acquire.html"><strong>lock_acquire</strong></a>,
<a href="lock_make_stable.html"><strong>lock_make_stable</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_try.html"><strong>lock_try</strong></a>,
<a href="lock_set_destroy.html"><strong>lock_set_destroy</strong></a>.