Re: [Pyobjc-dev] Achieving 1.0....

[pluto <pl...@ob...>]

hi folks,

i'm new to this list, i'm also new to macs and obj-c. i've been 
programming python for a several years as a living... and thats enough 
of an intro ;-)

On Monday, October 28, 2002, at 01:00 AM, Ronald Oussoren wrote:

> All,
>
> I just remembered one implementation issue that should be worked on 
> before reaching a 1.0 release: Thread safety.
>
> The current code is probably save for multi-threading, but I haven't 
> really checked this. Basicly I removed all static/global buffers while 
> working on the code.
>
> There are some more issues:
> 1. Python has a global interpreter lock. When one thread owns this 
> lock, no
>    other thread can execute python code. The bridge currently never 
> gives up
>    the GIL when moving into native code and we probably should. I have 
> not yet
>    researched what we should do with callbacks from Objective-C to 
> Python.
>
>    E.g. the NSApplicationMain wrapper should release the GIL before 
> calling
>    the actuall function, but how do you regain the GIL during calls to 
> methods
>    implemented in Python?
>

write a (objective) c wrapper that gets registered for the callback and 
takes a pointer to the python object to call. on callback reacquire the 
gil and call the object.

>    This is necessary to avoid unecessary blockage of Python threads 
> during
>    calls to Objective-C code.
>
> 2. Threads started using the Cocoa thread class(es) won't have a python
>    interpreter state. Special wrapping code should be written to 
> arrange for the
>    creation of that state. This can wait until item 1 is finished.
>

maybe it would be helpful to look at what pyqt or wxpython do in such 
cases.

cheers,

-p