Asynchronous RPC to a CompletionQueue that has been shutdown

[chh...@mesosphere.io]

Hi all,

I was wondering that, if I post an asynchronous RPC request to a `CompletionQueue` that has been shutdown,

how can I tell from the return value for error handling?

I'm asking this because the asynchronous request and the `Shutdown()` call might happen

in two different threads, and since the `CompletionQueue` is thread-safe,

I'm thinking if I can avoid introducing my own synchronization variables and

rely on the result of the asynchronous call to avoid concurrency issues.

Thanks,

Chun-Hung

[Yang Gao]

It is not clear to me what you meant by post an async rpc request to a cq. However, the user of a cq needs to guarantee that no new event is added to the cq after a shutdown is called. As a result, you most likely need some of your own synchronization.

Thanks.

[chh...@mesosphere.io]

Thanks for your answer.

What I meant is calling the asynchronous API with a cq that has been shut down.

It seems to me that it would be nicer if the grpc library has some way to report such an error,

say maybe returning a null unique_ptr of async reader when an event is added after cq is shut down.

But for now I'll add my own synchronization to prevent this.

Best,

Chun-Hung