On Thu, 20 Jun 2019 at 06:15, Matúš Valo <[email protected]> wrote:
> Hi All,
>
> Currently it is not possible to "kill" thread which is blocked. The
> rationale for this is handling situations when thread is blocked - e.g.
> when thread is quering DB when lock occurred on Database. In this case, the
> main thread has no way how to stop the blocked thread. Killing a thread is
> also popular question - see [1][2].
>
> pthread library and Windows API contains mechanisms for forced termination
> of threads - see [3] and [4]. It is also simple to use them using ctypes
> library but after this action one need to "clean" internal data structures
> which is bad practice:
>
> import time
> import threading
> import ctypes
>
> def handler():
> # blocked thread handler
> time.sleep(1000)
>
> t = threading.Thread(name='bar', target=handler)
> libpt = ctypes.cdll.LoadLibrary("libpthread.so.0")
>
> t.start()
> libpt.pthread_cancel(ctypes.c_ulong(t.ident))
> # This is nasty cleaning of internal python structures
> del threading._active[t.ident]
>
>
> Is if feasible to add canceling threads to python threading library? I am
> willing to help creating a patch (at least for linux).
Back in the day we used the .NET API for king threads from IronPython. It
made threads so much saner to work with. It's been an egregious lack in the
Python thread API for years and every time it's brought up people rush to
say you shouldn't do it as what you really want to do is something else.
Michael
>
> [1]
> https://stackoverflow.com/questions/323972/is-there-any-way-to-kill-a-thread
> [2] https://www.geeksforgeeks.org/python-different-ways-to-kill-a-thread/
> [3] http://man7.org/linux/man-pages/man3/pthread_cancel.3.html
> [4]
> https://docs.microsoft.com/en-us/windows/desktop/api/processthreadsapi/nf-processthreadsapi-terminatethread
> _______________________________________________
> Python-ideas mailing list -- [email protected]
> To unsubscribe send an email to [email protected]
> https://mail.python.org/mailman3/lists/python-ideas.python.org/
> Message archived at
> https://mail.python.org/archives/list/[email protected]/message/ZDERRWIBX7JP5F2VRTTGD4OMCUSMH3QB/
> Code of Conduct: http://python.org/psf/codeofconduct/
>
--
Michael Foord
Python Consultant, Contractor and Trainer
https://agileabstractions.com/
_______________________________________________
Python-ideas mailing list -- [email protected]
To unsubscribe send an email to [email protected]
https://mail.python.org/mailman3/lists/python-ideas.python.org/
Message archived at
https://mail.python.org/archives/list/[email protected]/message/RFEQKOULKVUSDPGNLSEYIS24RBBMD6AS/
Code of Conduct: http://python.org/psf/codeofconduct/
