[Tutor] Threads

[Gonçalo Rodrigues]

Terry Carroll wrote:

> On Sun, 14 Nov 2004, Kent Johnson wrote:
> 
> 
>>I'm starting to think there is a cultural bias against threads in the 
>>python community.
> 
> 
> I think there's a bias against threads in the tutorial mailing list, which 
> is kind of understandable.  It's a big leap in writing and debugging.  I 
> suspect that most programmers who are looking for help, and who are 
> proficient enough to use threads, would probably be hitting the 
> comp.lang.python newsgroup, rather than python-tutor.
> 

Agreed. Threads can seem simple but they have associated all the 
shenanigans of synchronization and deadlocking, starvation, race 
conditions, etc. And all these problems can be *very* hard to debug.

[snip]

> What's the ordinary way of telling a thread that it's no longer needed?
> 

Use the queue to pass an object that the thread can recognize as an 
order to shut down. Upon reception the thread can gracefully shut down, 
releasing all resources, etc. There is no way of this moment to kill 
threads from the outside (which is always a last option anyway -- a sort 
of "look, if you don't behave I'll kill you ok?") so you must build your 
framework with this kind of cooperation in mind.

With my best regards,
G. Rodrigues