NAME

       clReleaseEvent - Decrements the event reference count.

       cl_int clReleaseEvent(cl_event event);

PARAMETERS

       event
           Event object being released.

NOTES

       Decrements the event 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 clCreateUserEvent(3clc) that have not yet been set to status of CL_COMPLETE or an
       error. If the user event was used in the event_wait_list argument passed to a clEnqueue***
       API or another application host thread is waiting for it in clWaitForEvents(3clc), those
       commands and host threads will continue to wait for the event status to reach CL_COMPLETE
       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       principle no longer valid for him to change the status of the event to unblock all the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,
       cl_mem 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

       Returns CL_SUCCESS if the function executed successfully. Otherwise, it returns one of the
       following errors:

       •   CL_INVALID_EVENT if event is not a valid event object.

       •   CL_OUT_OF_RESOURCES if there is a failure to allocate resources required by the OpenCL
           implementation on the device.

       •   CL_OUT_OF_HOST_MEMORY if there is a failure to allocate resources required by the
           OpenCL implementation on the host.

SPECIFICATION

       OpenCL Specification[1]

SEE ALSO

       clGetEventInfo(3clc), clRetainEvent(3clc), clWaitForEvents(3clc)

AUTHORS

       The Khronos Group

COPYRIGHT

       Copyright © 2007-2011 The Khronos Group Inc.
       Permission is hereby granted, free of charge, to any person obtaining a copy of this
       software and/or associated documentation files (the "Materials"), to deal in the Materials
       without restriction, including without limitation the rights to use, copy, modify, merge,
       publish, distribute, sublicense, and/or sell copies of the Materials, and to permit
       persons to whom the Materials are furnished to do so, subject to the condition that this
       copyright notice and permission notice shall be included in all copies or substantial
       portions of the Materials.

NOTES

        1. OpenCL Specification
           page 185, section 5.9 - Event Objects