Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 957, in simulate
    status_path)
  File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1038, in _simulate_helper
    deb = self.install_file(trans, simulate=True, **trans.kwargs)
  File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 508, in install_file
    deb = self._check_deb_file(path, force, trans.uid)
  File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1158, in _check_deb_file
    pid, status = os.waitpid(pid, 0)
OSError: [Errno 4] Interrupted system call