def poll(self, pid):
        try:
            proc = self._procs[pid]
        except KeyError:
            return -errno.ENOENT
        if proc.poll() is None:
            return -errno.EAGAIN
        else:
            del self._procs[pid]
            return proc.exitstatus
Poll for async process. Returns exitstatus if done.
dataset/ETHPy150Open kdart/pycopia/QA/pycopia/remote/WindowsServer.py/Win32Agent.poll