I have an interface created with Glade. It contains a DrawingArea and buttons. I tried to create a Thread to refresh every X time my Canva. After a few seconds, I get error messages like: "X Window Server 0.0", "Fatal Error IO 11" Here is my code : import pygtk pygtk.require("2.0") import gtk import Canvas import threading as T import time import Map gtk.gdk.threads_init() class Interface(object): class ThreadCanvas(T.Thread): """Thread to display the map""" def __init__(self, interface): T.Thread.__init__(self) self.interface = interface self.started = True self.start() def run(self): while self.started: time.sleep(2) self.interface.on_canvas_expose_event() def stop(self): self.started = False def __init__(self): self.interface = gtk.Builder() self.interface.add_from_file("interface.glade") #Map self.map = Map.Map(2,2) #Canva self.canvas = Canvas.MyCanvas(self.interface.get_object("canvas"),self.game) self.interface.connect_signals(self) #Thread Canvas self.render = self.ThreadCanvas(self) def on_btnChange_clicked(self, widget): #Change map self.map.change() def on_interface_destroy(self, widget): self.render.stop() self.render.join() self.render._Thread__stop() gtk.main_quit() def on_canvas_expose_event(self): st = time.time() self.canvas.update(self.map) et = time.time() print "Canvas refresh in : %f times" %(et-st) def main(self): gtk.main() How can i fix these errors ?