[Boost-users] Passing io_service to socket in implementation file after initialization in header file

If I initialize an io_service object and a socket object in my header file, how do I pass io_service to the socket as a parameter in my implementation file? Take this header file as an example: // foo.h

#include

class foo { public:

foo(); // Constructor.

private:

boost::asio::io_service ios;

boost::asio::ip::udp::socket sock; };

And the corresponding implementation file: // foo.cc

#include "foo.h"

foo::foo() { sock(ios); // <-- This throws a compiler error. }

Why doing *sock(ios);* doesn't work? What is the proper way to do it? Thank you. Álvaro