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<!-- ================================ SYNOPSIS -->
<refnamediv id="clReleaseEvent">
Decrements the <varname>event</varname> reference count.
<refsynopsisdiv xmlns:xlink=""><title></title>
<link xlink:href="scalarDataTypes.html">cl_int</link>
<paramdef><link xlink:href="abstractDataTypes.html">cl_event</link><parameter>event</parameter></paramdef>
<!-- ================================ PARAMETERS -->
<refsect1 id="parameters">
<para>Event object being released.</para>
<!-- ================================ NOTES -->
<refsect1 id="notes"><title>Notes</title>
Decrements the <varname>event</varname> reference count.
The event object is deleted once the reference count becomes zero, the specific command
identified by this event has completed (or terminated) and there are no commands in
the command-queues of a context that require a wait for this event to complete.
Developers should be careful when releasing their last reference count on events
created by <citerefentry><refentrytitle>clCreateUserEvent</refentrytitle></citerefentry>
that have not yet been set to status of <constant>CL_COMPLETE</constant> or an error.
If the user event was used in the <varname>event_wait_list</varname> argument passed to
a <function>clEnqueue***</function> API or another application host thread is waiting
for it in <citerefentry><refentrytitle>clWaitForEvents</refentrytitle></citerefentry>,
those commands and host threads will continue to wait for the event status to reach
<constant>CL_COMPLETE</constant> or error, even after the user has released the object.
Since in this scenario the developer has released his last reference count to the
user event, it would be in principle no longer valid for him to change the status
of the event to unblock all the other machinery. As a result the waiting tasks will
wait forever, and associated events, <type>cl_mem</type> objects, command queues and
contexts are likely to leak. In-order command queues caught up in this deadlock may
cease to do any work.
<!-- ================================ ERRORS -->
<refsect1 id="errors"><title>Errors</title>
Returns <errorname>CL_SUCCESS</errorname> if the function executed
successfully. Otherwise, it returns one of the following errors:
<itemizedlist mark="disc">
<errorname>CL_INVALID_EVENT</errorname> if <varname>event</varname> is not a
valid event object.
<errorname>CL_OUT_OF_RESOURCES</errorname> if there is a failure to allocate
resources required by the OpenCL implementation on the device.
<errorname>CL_OUT_OF_HOST_MEMORY</errorname> if there is a failure to allocate
resources required by the OpenCL implementation on the host.
<!-- ================================ EXAMPLE -->
<refsect2 id="example1">
<informaltable frame="none">
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Example goes here - it will be set in "code" type with white space preserved.
<!-- ================================ SPECIFICATION -->
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<refsect1 id="specification"><title>Specification</title>
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<olink uri="clReleaseEvent">OpenCL Specification</olink>
<!-- ================================ ALSO SEE -->
<refsect1 id="seealso"><title>Also see</title>
<!-- ================================ COPYRIGHT -->
<!-- Content included from -->
<refsect3 id="Copyright"><title></title>
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<para />
<!-- 18-Oct-2011 -->