Microsoft.R.Host.Client.RHost.Run C# (CSharp) Method

        public async Task Run(CancellationToken cancellationToken = default(CancellationToken)) {
            TaskUtilities.AssertIsOnBackgroundThread();

            if (_runTask != null) {
                throw new InvalidOperationException("This host is already running.");
            }

            var cts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken, _cts.Token);

            try {
                _runTask = RunWorker(cts.Token);
                await _runTask;
            } catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested || _cts.Token.IsCancellationRequested) {
                // Expected cancellation, do not propagate, just exit process
            } catch (MessageTransportException ex) when (cancellationToken.IsCancellationRequested || _cts.Token.IsCancellationRequested) {
                // Network errors during cancellation are expected, but should not be exposed to clients.
                throw new OperationCanceledException(new OperationCanceledException().Message, ex);
            } catch (Exception ex) {
                var message = "Exception in RHost run loop:\n" + ex;
                _log.WriteLineAsync(LogVerbosity.Minimal, MessageCategory.Error, message).DoNotWait();
                Debug.Fail(message);
                throw;
            } finally {
                cts.Dispose();

                // Signal cancellation to any callbacks that haven't returned yet.
                _cts.Cancel();

                _requests.Clear();
            }
        }