[Twisted-Python] spawnProcess and when to kill

hi, all I start a process using spawnProcess and want to kill when my certain Factory stops. something I wrote like these ---------- p = SomeProtocol(ProcessProtocol) reactor.spawnProcess(p, 'twistd', ['twistd', '-y', 'anotherMain.py'], {}) ---------- class Factory(ServerFactory): ... def StopFactory(self): # which is the p above p.transport.signalProcess("KILL") I thought the subprocess will be killed which is not. What's wrong with my code? Thanks! Regards, Huang 黄 轶明 mail: hoooooosety@gmail.com phone: 18620129285