Waiting for a specific event to be available to read

Hi all,
I have a situation where I know that an event will be written to a stream, but it might not be there yet (in this case, because I know that another subscriber is in the process of writing it but it’s a fairly common scenario in an eventually consistent system).

Is there anyway to wait for the event asynchronously for the event to appear using ReadEvent, or am I required to poll until it is available?

Thanks,

Michael

To be more precise: I know the exact event number in the stream that I expect to be created, and I want to wait for the stream to reach that length.

A simple subscription could be enough I think

open/closing subscriptions like this if at scale could also be a bad
idea, better to just poll at that point.