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That's excellent (sorry I have not seen this in the docs before). However I think it's not a good idea to create your own futures. This does not scale well nor does it compose with std::future or boost::future. Is there a way to use whatever futures (or more specifically, threading implementation) the user decides to use?

The boost::compute::future class wraps a cl_event object which is used to monitor the progress of a compute kernel. I'm not sure how to achieve this with std::future or boost.thread's future (or even which to chose for the API). Any pointers (or example code) would be greatly appreciated.

Yes, that's exactly the problem. It is nothing specific to your particular library but a general issue to solve. In the library we develop (HPX, https://github.com/STEllAR-GROUP/hpx/) we face the same issue of having to rely on our own synchronization primitives which makes it impossible to reuse std::future (or boost::future). Any suggestion on how to create specialization/customization points allowing to make boost::future universally applicable would be most appreciated. Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu