I was wondering if it were possible to launch an external command (system call) when a transaction sent by a node is confirmed?
For example if node A runs pyethapp (in the context of a private blockchain) as:
$ pyethapp -c eth.network_id=1337 -c node.privkey_hex=091bd6067cb4612df85d9c1ff85cc47f259ced4d4cd99816b14f35650f59c322 -b 'enode://288b97262895b1c7ec61cf314c2e2004407d0a5dc77566877aad1f2a36659c8b698f4b56fd06c4a0c0bf007b4cfb3e7122d907da3b005fa90e724441902eb19e@0.0.0.0:30303' -c eth.genesis_hash=283bd9430c5f3114872f93beefe99d6626980b3a4a18a44ddd27749cd89688f2 -m 50 run
and then node B connects to it through pyethapp:
$ pyethapp -c eth.network_id=1337 -b 'enode://288b97262895b1c7ec61cf314c2e2004407d0a5dc77566877aad1f2a36659c8b698f4b56fd06c4a0c0bf007b4cfb3e7122d907da3b005fa90e724441902eb19e@192.168.2.12:30303' -c eth.genesis_hash=283bd9430c5f3114872f93beefe99d6626980b3a4a18a44ddd27749cd89688f2 run
and sends a transaction from an account on its end to one on A's end can it take action (initiate a system call) once the transaction is confirmed?