Fix PcapngWriter 'Already registered' on ephemeral port reuse - #620
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Rotate stale writer in DirectCaptureContext.Subscribe and decouple subscription id from 5-tuple so a linger-delayed Unsubscribe of the previous connection no longer yanks the new writer.
This was referenced Apr 20, 2026
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Summary
When the OS reuses an ephemeral local port during the linger tear-down of a previous outbound capture,
DirectCaptureContext.Subscribecollided on the connection 5-tuple key and calledPcapngWriter.Registera second time on an already-registered writer, throwingInvalidOperationException: Already registered!.Fix rotates the stale writer in
Subscribeand decouples the subscription id (lifecycle) from the 5-tuple key (packet routing).SyncWriterQueuenow holds two dicts andTryRemoveBySubIdonly removes by key when instances still match, so the old connection's linger-delayedUnsubscribeis a safe no-op after rotation.No change to
ICaptureContextshape or the out-of-proc wire protocol.