public override string ToString()
            {
                try
                {
                    string spacer;
                    switch (((uint)Thread.VolatileRead(ref loop)) % 4)
                    {
                        case 0: spacer = @" - "; break;
                        case 1: spacer = @" \ "; break;
                        case 2: spacer = @" | "; break;
                        case 3: spacer = @" / "; break;
                        default: spacer = " ! "; break;
                    }
                    return (server.IsSlave ? "S " : "M ") + EndPointCollection.ToString(EndPoint) + spacer + OpCount + ": " + state;
                }
                catch (Exception ex)
                {
                    return ex.Message;
                }

            }
            public long OpCount { get;set; }
            int loop;
            internal void SetState(string msg)
            {
                state = msg;
                Interlocked.Increment(ref loop);
                Interlocked.Exchange(ref concern, 0);
            }