On Wed, 27 Jun 2012, Rutger ter Borg wrote: > > Dear list, > > I'm currently writing a Boost.Asio-like interface to librados.hpp. Most things > are working like expected, and some things I couldn't figure out from the > available docs and code. I have itemized a couple of questions below. > > * to avoid allocations done by rados, I'm currently using > buffer::create_static() for both reads and writes. I suppose this is ok? > > * suppose you have the following code example > > boost::asio::io_service ios; > pool pool( "some pool", ios ); > > std::string some_data( "this is an example string of data" ); > pool.async_write_object_at( "hello", 0, boost::asio::buffer( some_data ), > &done ); > > ios.run(); > > with respect to this interface, I have the following questions: > > a) the IoCtx's synchronous read() and write() functions return the number of > bytes read and written; is there a way to get to this number from > AioCompletion? I would like to define the function signature for the callback > handler (see 'done' in the example above) something like > > void( const boost::system::error_code&, std::size_t ) > > where the second argument would be the number of bytes transferred. There is a get_return_value() method on the AioCompletion that gives you bytes read (for reads). For write operations, it is always 0 (success) or an error code. > b) is it possible to cancel outstanding asynchronous operations? I.e., have > the possibility to implement something like > > pool.cancel(); Not currently. This is probably something we should add. sage -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
