In the current implementation of byLineAsync, the created thread can not be terminated at any time manually. It are permanently executed until the end of communication.
The code is already provisioned to handle that, just need to enhance WorkerThreadProtocol to add an abort method that sends a bool to workerTid. This will be received in _receiveAsyncChunks and tell curl to abort the request (by returning 0 from onReceive).
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