[Tutor] DOS box only works a few times

[Georg Simon]

Since I am learning not only Python but Tkinter too, I am not able to
run my programs more than a few times.
>From IDLE I write the following example to the hard disk.
-------------------------------------
from Tkinter import *

root = Tk()

w = Label(root, text="Hello, world!")
w.pack()

root.mainloop()
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Then I open the DOS box, type p and Enter for my batch file p.bat and
wait for the Tkinter window. The Tkinter window I close with Alt+F4. The
DOS prompt appears and I start again entering p . After 2 to 7
repetitions ( count not reproducable ) the DOS prompt no longer appears
but only the DOS cursor. The DOS box is unable to receive any
keystrokes.
Similar results I get with three different computers, Windows 95 and
Windows 98, up to 128 MB RAM, and different Tkinter examples. An empty
example like
-------------------------------------
from Tkinter import *

root = Tk()

root.mainloop()
-------------------------------------
seems to be more dangerous.

Georg Simon