ROS Qt Interrupted System Call On Plugin Startup

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I've recently been working on a python widget for rqt that creates a separate thread to read joystick data in from a pipe. I've tested it as a standalone python program and confirmed that it's getting valid data. However, when I put it into a python plugin for rqt that I've already created and tested, it crashes. After some tweaking of the code, it looks like it crashes at the end of the __init__ function in the plugin with IOError: [Errno 4] Interrupted system call when the pipe read is interrupted.

The initialization is basically:

1. Create a joystick object that creates a thread to endlessly read in data from /dev/input/js0; start running it
2. Create thread to endlessly check the Joystick object containing this other thread to look for new data; start running it
3. Wait 5 seconds, during which joystick data prints out fine as I would expect
4. The 5 Second wait ends, IOError: [Errno 4] Interrupted system call is thrown, and rqt loads as normal

A snippet of the plugin code is below. The Joystick class being referenced creates a thread in the same manner, opens a pipe using self._pipe = open('/dev/local/js0', 'r'), then reads in raw data for parsing using for character in self._pipe.read(1):

    class Joystick(Plugin):
      # Variables...
      def __init__(self, context):
          # Some initialization code here...
          #...
          # Create the joystick object and run its thread
          self._joystick_reader = LinuxJoystickReader()
          self._joystick_reader.initialize('/dev/input/js0')
          self._joystick_reader.start()
          # Create a local thread and run it to print the joystick data
          self._joystick_thread_run = True
          self._joystick_read_thread = Thread(target=self.pub_joystick, args=())
          self._joystick_read_thread.start()
          # Sleep, during which the data prints out fine
          time.sleep(5)
          # -- ERROR --
          # File "joystick_class.py" line 35, in read_pipe
          # for character in self._pipe.read(1):
          # IOError: [Errno 4] Interrupted system call

       def pub_joystick(self):
         while self._joystick_thread_run:
           if self._joystick_reader.has_new_data():
             pub_str = str(self._joystick_reader.get_data_array()[0]) + ", " + str(self._joystick_reader.get_data_array()[1])
             print pub_str
         self._joystick_reader.stop()