private async Task ProcessChild(ThreadProgress state)
        {
            Debug.Assert(state.Newpid != 0, "Child process id not found.");
            if (state.Newpid != 0)
            {
                uint inf = _process.InferiorByPid(state.Newpid);
                if (inf != 0)
                {
                    await _process.ConsoleCmdAsync("inferior " + inf.ToString(), allowWhileRunning : false);

                    if (!string.IsNullOrEmpty(_mainBreak))
                    {
                        await _process.MICommandFactory.BreakDelete(_mainBreak);

                        _mainBreak = null;
                    }
                    state.State = State.AtSignal;
                    await _process.MICommandFactory.Signal("SIGSTOP");  // stop the child
                }
            }
        }