func HostPort(addr string, port interface{}) string
HostPort format addr and port suitable for dial
func Listen(addr string, fn func(string) (net.Listener, error)) (net.Listener, error)
Listen takes addr:portmin-portmax and binds to the first available port Example: Listen("localhost:5000-6000", fn)
func Proxy(service string, address []string) (string, []string, bool)
Proxy returns the proxy and the address if it exits