I want to do the following with Boost Asio. I have a socket and I want to register a callback to be called when data is available for reading/writing on the socket, but I do
You are looking for reactor-style operations. These can be obtained by providing boost::asio::null_buffers to the asynchronous operations. Reactor-style operations can be useful for integrating with third party libraries, using shared memory pools, etc. The Boost.Asio documentation provides some information and the following example code:
ip::tcp::socket socket(my_io_service);
...
socket.non_blocking(true);
...
socket.async_read_some(null_buffers(), read_handler);
...
void read_handler(boost::system::error_code ec)
{
if (!ec)
{
std::vector<char> buf(socket.available());
socket.read_some(buffer(buf));
}
}
Boost.Asio also provides an official nonblocking example, illustrating how to integrate with libraries that want to perform the read and write operations directly on a socket.