+ // Manages a cache of RPC connections. Usage:
+ // if (auto cl = rpcc::bind_cached(dst))
+ // ret = cl->call(...);
+ // where the string dst has the form "host:port". Because bind_cached()
+ // may block, callers should probably not hold mutexes.
+ static shared_ptr<rpcc> bind_cached(const string & destination);
+ static void unbind_cached(const string & destination);
+