// Clear so we can be called multiple times without crashing.
		doneCh = nil
	}, &closeNotifier{rc: r.Body, done: bodyDoneCh}
}

// keepHTTPResponseAlive can be used to avoid timeouts with long storage
// operations, such as bitrot verification or data usage scanning.
// keepHTTPResponseAlive may NOT be used until the request body has been read,
// use keepHTTPReqResponseAlive instead.
// Every 10 seconds a space character is sent.