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How to kill a thread from another thread ?

Richard Gruet rgruet at ina.fr
Sat Nov 11 12:17:41 EST 2000 
Robert Amesz wrote:

> Aahz Maruch wrote:
>
> >In article <3A0A6715.35C19F47 at ina.fr>, Richard Gruet
> ><rgruet at ina.fr> wrote:
> >>
> >>Does someone know how to kill a Python thread from another Python
> >>thread (in the same process) ?
> >
> >You don't.  You need to set up each of your threads so that they
> >look for some kind of signal to kill themselves (which means
> >returning).  It has been argued that the ability to kill threads is
> >necessary for server applications, but I haven't seen any powerful
> >arguments in favor of that.
>
> How about doing blocking I/O in a thread? If something goes wrong the
> thread might block forever. Anticipating the response: "So don't do
> blocking I/O", I'd like to add that you may not have that option,
> because the blocking call could be in another module which you need to
> use but didn't write yourself

> If Python uses non-blocking I/O internally, *and* it had the ability to
> raise exceptions in another thread you would have a very powerful
> mechanism to kill threads and still have a thread clean up after itself
> (which is, I think, the most powerful argument against having threads
> kill each other).

In my particular case, I want to kill the thread from the thread which created
it when something is going wrong (e.g. a timed out I/O) and furthermore I
performed the cautious operation in a separate thread precisely to be avoid
getting stuck in case of problem.
To me this is a good reason to want to kill a thread in this case. I agree that
*usually* killing a thread without clean-up is not a good policy!

This leads me back to my original question: how can I do that (and in a portable
way) ? Apparently there is no obvious solution.
To use a separate process to execute an operation is quite inefficient (although
in this case I know how to kill the process).

Richard Gruet
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