| cl_int clRetainCommandQueue( | cl_command_queue command_queue ) | 
clCreateCommandQueueWithProperties performs an implicit retain. This is very helpful for 3rd party libraries, which typically get a command-queue passed to them by the application. However, it is possible that the application may delete the command-queue without informing the library. Allowing functions to attach to (i.e. retain) and release a command-queue solves the problem of a command-queue being used by a library no longer being valid.
Returns CL_SUCCESS if the function executed successfully, or one of the errors below:
command_queue
              is not a valid command-queue.
             Copyright © 2007-2013 The Khronos Group Inc. 
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Copyright © 2007-2013 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.