"sir_alex" <[EMAIL PROTECTED]> writes: > Hello everybody! I have a couple of questions about threads: the first > is, is there the possibility to cancel a thread while it is executing > (like the C function thread_cancel), for implementing something like an > "abort" button?
As far as I know, python thread does not support thread cancellation, and that is probably a good thing. Thread cancellation can be _very_ difficult to get right. If not done right, you end up with resource leaks and/or deadlock. It is much better to use some explicit synchronization mechanism to tell a thread that it shall terminate itself. You could, for example, use a state variable, a mutex and a condition variable. > And the second is, i have a GUI in which there's a > button that launches a thread implemented using the threading module > (creating a class which inherits from threading.Thread and overriding > __init__ and run), i chose to use threads to avoid the problem of > freezing my windows, but after i call classobject.start() this happens: > if i then call classobject.join(), then the button is freezed, because > now the button waits the end of the thread, And that is only to be expected. Join is not a mechanism for terminating threads, it us a mechanism for _blocking__ until the designated thread terminates. > if i don't make this call > the button releases itself (that is a good behavior) but the thread > freezes until i give a ctrl-c in the console from which i launched my > app. So, how can i make my button release while the thread is > executing? (my GUI is implemented in GTK and i use libglade) (sorry for > the length of this post...) When the button is being pressed, use some explicit synchronization to inform the thread that it shall terminate. -- http://mail.python.org/mailman/listinfo/python-list
