PySide, pySerial and threading causes segfault

MrRadiotron

I'm trying to use PySide and pySerial to make a cross-platform app that interacts with the serial port. I originally used Qtimers to poll the serial for data, but this put a large load on the cpu. So I've been attempting to use threads instead.

unfortunately using threads causes either Qt or pySerial to Segfault.

I've tried both python threads and QThreads, same problem, it happens on OSX, windows 8 and Ubuntu 12.04. using python 2.7 and Qt4

"This question seemed to have a similar problem,":http://stackoverflow.com/questions/18378536/using-a-qthread-in-pyqt-for-serial-communication-w-pyserial

"this thread also seems to be a similar problem":http://www.gossamer-threads.com/lists/python/python/1064621

below is a small app that recreates the problem

@
#! /usr/bin/python
import sys
import serial
import threading
from PySide import QtCore, QtGui, QtUiTools

class serial_port_class(object):
def init(self):
self.connected = False

def __del__(self):
    self.disconnect_port()

def connect_port(self):
    try:
        self.serial_port = serial.Serial("/dev/tty.usbmodem1451", 9600, timeout = None)
        self.connected = True
    except serial.SerialException, e:
        self.connected = False
    if self.connected:
        self.serial_thread = threading.Thread(target=self.recieve_port, args=(self))
        self.serial_thread.start()

def disconnect_port(self):
    self.connected = False
    self.serial_thread.join()
    self.serial_port.close()

def recieve_port(self):

    while self.connected:
        try:
            text = self.serial_port.read(1)
            if text != '':
                print "text"
        except serial.SerialException, e:
            connected = False

class KeyPressEater(object):
def connect_port(self):
self.serial_thread = threading.Thread(target=self.eventFilter)
self.serial_thread.start()

def eventFilter(self):
    global serial_port
    while serial_port.connected == True:
        ch = raw_input()
        if serial_port.connected == True:
            serial_port.serial_port.write(ch)
        return QtCore.QObject.eventFilter(self, obj, event)

def main():
global serial_port
serial_port = serial_port_class()
serial_port.connect_port()
heyeater = KeyPressEater()

if serial_port.connected== True:
    heyeater.connect_port()
    heyeater.serial_thread.join()

if name == 'main':
main()

@

sometimes it takes a bit of data IO to trigger the segfault, sometimes a single character will trigger it...

I'm not really sure how I would go about debugging this further....

All help is appreciated!!!!!!