Virtualvfunc_Given connection to communicate with a proxy (eg, a
Gio.SocketConnection that is connected to the proxy server), this
does the necessary handshake to connect to proxy_address, and if
required, wraps the Gio.IOStream to handle proxy payload.
Optionalcancellable: Gio.CancellableVirtualvfunc_Asynchronous version of g_proxy_connect().
Optionalcancellable: Gio.CancellableOptionalcallback: AsyncReadyCallback<Gio.Proxy.Interface>Virtualvfunc_Virtualvfunc_Some proxy protocols expect to be passed a hostname, which they
will resolve to an IP address themselves. Others, like SOCKS4, do
not allow this. This function will return false if proxy is
implementing such a protocol. When false is returned, the caller
should resolve the destination hostname first, and then pass a
Gio.ProxyAddress containing the stringified IP address to
g_proxy_connect() or g_proxy_connect_async().
Interface for implementing Proxy. Contains only the virtual methods that need to be implemented.