Tkinter and thread. out of stack space (infinite loop?)

Question

I\'m experimenting with Tkinter and the threads mechanism. Can anyone explain why this raises the exception:

 out of stack         


        

Answer 1

You have a couple of fatal flaws in your code. For one, you simply can't write code that touches tkinter widgets from more than one thread. You are creating the root window in the main thread, so you can only ever directly access widgets from the main thread. Tkinter is not thread safe.

The second problem is that you have an infinite loop that is constantly appending to the text widget. It has no choice but to eventually run out of memory.

To solve your problem you should:

1. not have an infinite loop that forever appends to the text widget
2. not access any widgets from more than a single thread

If you want to run a function once a second, there are better ways to do that than with threads. In short:

def do_every_second():
    cont.insert("end", str(n) + "\n")
    root.after(1000, do_every_second)

This will cause do_every_second to do whatever it does, then arranges for itself to be called again one second in the future.