topic Pure Python COM objects cause Beta 2 crash in Geoprocessing Questions

Pure Python COM objects cause Beta 2 crash

MarkCederholm — Fri, 12 Feb 2010 13:55:29 GMT

Pure Python COM objects work just fine in ArcGIS 9.3.1, but in Beta 2 they cause ArcMap and ArcCatalog to crash on closing. Here's a simple test:

1) Create a simple COM object using the instructions at:
http://starship.python.net/crew/theller/comtypes/server.html

2) Open ArcMap or ArcCatalog and type the following in the Python window:
from comtypes.client import CreateObject
o = CreateObject("MyTypeLib.MyObject")

3) Close ArcMap or ArcCatalog

4) Boom! 😉

Pure Python COM objects cause Beta 2 crash

JasonScheirer — Fri, 12 Feb 2010 22:36:09 GMT

Looks like a double free on the COM object when ArcMap/Catalog closes down the Python interpreter for that process. Are there any known issues in COMTypes itself? Is there an explicit addref call you need to execute on the object when you start using it?

We don't link against a debug build of Python in the ArcObjects stack, so I can't dig too much further into the Python to see what's going on here. Sorry.

Pure Python COM objects cause Beta 2 crash

MarkCederholm — Mon, 15 Feb 2010 12:32:10 GMT

CreateObject automatically adds a ref, just as del automatically removes it. Even after the object is supposedly freed, the bomb still occurs. I tried adding an extra ref and that did no good. I know of no current issues with comypes but I'll do some looking; no bombs occur when the object is used in a normal Python session.

Pure Python COM objects cause Beta 2 crash

MarkCederholm — Thu, 08 Apr 2010 16:05:35 GMT

Looks like it's fixed in the RC!

Pure Python COM objects cause Beta 2 crash

JasonScheirer — Thu, 08 Apr 2010 20:13:08 GMT

Awesome, good to hear.