Python Mapscript Crashes

[Frank Warmerdam]

Umberto Nicoletti wrote:
> Unfortunately the ability of mapscript to deal with garbage collection
> is still limited.
> 
> For example: the host language (in your case, python) will free an
> object because it is no longer reachable without knowing that
> mapscript still has references to it.
> As soon as mapscript dereferences the pointer a segfault will occur.
> 
> As of now there are some methods that are safe to use in some ways,
> but I can't provide a list right now.

...

> On 10/17/06, Stéphane COLZY <stephane.colzy at magellium.fr> wrote:

>> Have you already encountered this exception with Python/MapScript :
>>
>>
>>
>> Exception exceptions.AttributeError: "'NoneType' object has no attribute
>> 'currentThread'" in <bound method mapObj.__del__ of <mapscript.mapObj; 
>> proxy
>> of C mapObj instance at _10108002_p_map_obj>> ignored
>>
>> I'm using python/mapscript from MS4W 1.19 and Python 2.4.3

Stephane,

I think it would be helpful if you could boil this down to a minimal set
of python mapscript calls to demonstrate the problem and submit this as a
bug report in the mapserver bugzilla.  I am not aware of systematic problems
in garbage collection in MapScript but if there are, a concrete demonstration
would be helpful.

Best regards,
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