Closed
Description
As per the last point in #150. There should be a means to spy on a local Publication only.
Subscribe to a Channel + Stream ID for any publisher on the same media driver ("Spying" on a normal publisher for purposes such as local processing, archival, etc.). Ignoring external publishers.
This includes addition of methods to create "Spy" Subscriptions for specific Publications, Aeron.addSpy(Channel, StreamID). This is a Subscription object and can be polled as normal and uses same semantics for data delivery as other Subscriptions.