Christopher Pisz wrote:

I have a Server class inherited from a Listener class, with the latter being bases on the boost::asio example code.

My problem is that the Listener class requires am boost::asio::io_service & in order to initialize its member variables.

I wanted the Server class to be responsible for starting a thread, owning the io_service, and running it.

It seems I cannot do that!

class Server : public Listener { public: Server() : Listener(ioService_) { }

// Snip

protected:

boost::asio::io_service ioService_; };

class Listener { public:

Listener(boost::asio::io_service & ioService) : socket_(ioService) { }

// Snip

protected: boot::asio::ip::tcp::socket socket_; };

The above throws an unhandled exception in the initialization of the derived class.

I suppose this is because ioService_ is not constructed yet? Since the C++ rules, if I remember correctly, say the base class gets constructed before the members of the derived?

So, I tried:

Server() : ioService_(), Listener(ioService_) { }

to try and force it, but it still throws an exception.

The only way to get it to not throw an exception is to create the instance to io-service in main() and then pass it as a reference into the class constructor. If I do that, then there is no way for any class in my inheritance hierarchy to own the io_service. As such, I cannot start and stop it either.

Is there any way to get ownership of the io_service in my class hierarchy?

class Server: protected boost::asio::io_service, public Listener Server (): Listener (*this) HTH, Chris