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//#define BOOST_RESULT_OF_USE_DECLTYPE 1
#include "afio_pch.hpp"
int main(void)
{
//[completion_example1
// Create a dispatcher instance
std::shared_ptr<boost::afio::dispatcher> dispatcher=
boost::afio::make_dispatcher().get();
// Completion handlers are the lowest level completion routine available, and therefore the least
// overhead but at the cost of considerable extra programmer effort. You almost certainly want
// to use the call() member function instead.
// First create some callable entity ...
auto completer=[](
/* These are always the standard parameters */
size_t id, boost::afio::future<> precondition,
/* From now on user defined parameters */
std::string text)
/* This is always the return type */
-> std::pair<bool, std::shared_ptr<boost::afio::handle>>
{
/* id is the unique, non-zero integer id of this op.
precondition is the op you supplied as precondition. As it will by definition
have completed by now, you can fetch from its h member variable a shared pointer
to the shared stl_future containing either the output handle or the error state.
*/
std::cout << text << std::endl;
// Return whether this completion has completed now or is it deferred,
// along with the handle we pass onto any completions completing on this op
// Note that op.get() by default rethrows any exception contained by the op.
// Normally this is highly desirable.
return std::make_pair(true, precondition.get_handle());
};
// Bind any user defined parameters to create a proper boost::afio::dispatcher::completion_t
std::function<boost::afio::dispatcher::completion_t> boundf=
std::bind(completer,
/* The standard parameters */
std::placeholders::_1, std::placeholders::_2,
/* Any values for the user defined parameters. Remember ALWAYS to pass by value! */
std::string("Hello world"));
// Schedule an asynchronous call of the completion with some bound set of arguments
boost::afio::future<> helloworld=
dispatcher->completion(boost::afio::future<>() /* no precondition */,
std::make_pair(boost::afio::async_op_flags::none, boundf));
// Create a boost::stl_future<> representing the ops passed to when_all_p()
boost::afio::stl_future<std::vector<std::shared_ptr<boost::afio::handle>>> stl_future
=boost::afio::when_all_p(helloworld);
// ... and wait for it to complete
stl_future.wait();
//]
return 0;
}
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