self._poller.unregister IOError: [Errno 2] No such file or directory

[mdavidsaver]

So I finally realized what is happening here. The issue is that I am trying to be robust by preventing recvfrom() on the broadcasting socket. I do this by calling pauseProducing() for the Transport associated with a UDP socket. Apparently this doesn't work work with the epoll backend.

Traceback (most recent call last):
  File "/usr/bin/twistd", line 11, in <module>
    load_entry_point('Twisted==18.9.0', 'console_scripts', 'twistd')()
  File "/usr/lib/python2.7/dist-packages/twisted/scripts/twistd.py", line 31, in run
    app.run(runApp, ServerOptions)
  File "/usr/lib/python2.7/dist-packages/twisted/application/app.py", line 674, in run
    runApp(config)
  File "/usr/lib/python2.7/dist-packages/twisted/scripts/twistd.py", line 25, in runApp
    runner.run()
  File "/usr/lib/python2.7/dist-packages/twisted/application/app.py", line 385, in run
    self.postApplication()
  File "/usr/lib/python2.7/dist-packages/twisted/scripts/_twistd_unix.py", line 254, in postApplication
    self.startApplication(self.application)
  File "/usr/lib/python2.7/dist-packages/twisted/scripts/_twistd_unix.py", line 442, in startApplication
    service.IService(application).privilegedStartService()
  File "/usr/lib/python2.7/dist-packages/twisted/application/service.py", line 283, in privilegedStartService
    service.privilegedStartService()
  File "/home/mdavidsaver/work/epics/recsync/server/recceiver/application.py", line 86, in privilegedStartService
    self.udp.startListening()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/udp.py", line 179, in startListening
    self._connectToProtocol()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/udp.py", line 217, in _connectToProtocol
    self.protocol.makeConnection(self)
  File "/usr/lib/python2.7/dist-packages/twisted/internet/protocol.py", line 771, in makeConnection
    self.doStart()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/protocol.py", line 727, in doStart
    self.startProtocol()
  File "/home/mdavidsaver/work/epics/recsync/server/recceiver/announce.py", line 40, in startProtocol
    self.transport.pauseProducing()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/abstract.py", line 470, in pauseProducing
    self.stopReading()
  File "/usr/lib/python2.7/dist-packages/twisted/internet/abstract.py", line 422, in stopReading
    self.reactor.removeReader(self)
  File "/usr/lib/python2.7/dist-packages/twisted/internet/epollreactor.py", line 172, in removeReader
    EPOLLIN, EPOLLOUT)
  File "/usr/lib/python2.7/dist-packages/twisted/internet/epollreactor.py", line 160, in _remove
    self._poller.unregister(fd)
IOError: [Errno 2] No such file or directory

[mdavidsaver]

The workaround, as mentioned in server/README, is to pass -r poll.

twistd -r poll -n recceiver -f demo.conf