Direct control of the callback queue?
Is it possible to directly access and modify the ros callback queue such as in the boost::asio library that we can use:
boost::asio::io_service::post
to post a callback function to the deseried event queue.
Would a custom message filter solve your problem? Maybe modeled after https://github.com/ros/ros_comm/blob/...
#q219292 asks about it but no answers unfortunately.
More description of what you want to accomplish helps.