private async Task SendAsync(Message message, CancellationToken ct)
{
TaskUtilities.AssertIsOnBackgroundThread();
_log.Request(message.ToString(), _rLoopDepth);
try {
await _transport.SendAsync(message, ct);
} catch (MessageTransportException ex) when(ct.IsCancellationRequested)
{
// Network errors during cancellation are expected, but should not be exposed to clients.
throw new OperationCanceledException(new OperationCanceledException().Message, ex);
} catch (MessageTransportException ex) {
throw new RHostDisconnectedException(ex.Message, ex);
}
}