Re: [comtypes-users] passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)
[EMAIL PROTECTED] schrieb: > Seems to stomp memory. A work around is to declare the parameter as a > POINTER(GUID) instead of GUID and pass a copy of the GUID instance byref > [this should be what happens under the covers]. I'm not sure if this is a > comtypes or ctypes issue; it likely applies to other "large" datatypes as > well. I'm using python-2.5.2.amd64.msi, > ctypes-1.0.2.win32-py2.5-AMD64.msi and comtypes-0.4.2.zip. It looks like a ctypes bug on Windows/AMD64, structures are not passed correctly by value. I'm looking into it but it may take a few days. Thanks for the heads up and the nice diagnosis, Thomas - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php ___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users
Re: [comtypes-users] passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)
Sorry, I wasn't very clear. With the original code, the call itself reports success (return code 0), but I can't verify it as attempting access the parameters causes an exception [eg print str(snapshot_id) raises "WindowsError: exception: stackoverflow" in _StringFromCLSID]. If I catch the exception and try to continue, I get other WindowsError exceptions, typically from attempting to access bad memory addresses. Peter [EMAIL PROTECTED] schrieb: > The following workaround works with 64-bit (and I assume 32-bit) pythons: > ... > > The following (original code) only works with 32-bit python (and seems to > cause a memory stomp with 64-bit python) [here guid_null is passed by > value]: > ... I understand what you mean, except I do NOT understand what 'cause a memory stomp' mean. Does the code change the passed in guid_null, which you didn't expect, or what? Thanks, Thomas - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php ___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users
Re: [comtypes-users] passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)
[EMAIL PROTECTED] schrieb: > The following workaround works with 64-bit (and I assume 32-bit) pythons: > ... > > The following (original code) only works with 32-bit python (and seems to > cause a memory stomp with 64-bit python) [here guid_null is passed by > value]: > ... I understand what you mean, except I do NOT understand what 'cause a memory stomp' mean. Does the code change the passed in guid_null, which you didn't expect, or what? Thanks, Thomas - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php ___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users
Re: [comtypes-users] passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)
The following workaround works with 64-bit (and I assume 32-bit) pythons: ... VSS_ID = GUID ... COMMETHOD([], HRESULT, 'AddToSnapshotSet',(['in'],VSS_PWSZ,'pwszVolumeName'),(['in'],POINTER(VSS_ID),'ProviderId'),(['in'],POINTER(VSS_ID),'pidSnapshot')), ... snapshot_id = GUID() guid_null = GUID() vss.AddToSnapshotSet(u"c:\\", byref(guid_null), byref(snapshot_id)) ... The following (original code) only works with 32-bit python (and seems to cause a memory stomp with 64-bit python) [here guid_null is passed by value]: ... VSS_ID = GUID ... COMMETHOD([], HRESULT, 'AddToSnapshotSet',(['in'],VSS_PWSZ,'pwszVolumeName'),(['in'],VSS_ID,'ProviderId'),(['in'],POINTER(VSS_ID),'pidSnapshot')), ... snapshot_id = GUID() guid_null = GUID() vss.AddToSnapshotSet(u"c:\\", guid_null, byref(snapshot_id)) ... The original code was auto-generated from a header file. Note that the actual calling sequence for AddToSnapshotSet is the same in both cases (at the machine level a pointer to the guid_null value is passed). Technically, for the work around to have the same effect I should first copy guid_null to a temporary and pass a pointer to that instead. Peter [EMAIL PROTECTED] schrieb: [passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)] > Seems to stomp memory. I'm not a native english speaker and do not understand what you mean. Also, can you give a description or a code sample to illustrate the problem? Best would be if you can submit a test case. > A work around is to declare the parameter as a POINTER(GUID) instead > of GUID and pass a copy of the GUID instance byref [this should be > what happens under the covers]. I'm not sure if this is a comtypes > or ctypes issue; it likely applies to other "large" datatypes as > well. I'm using python-2.5.2.amd64.msi, > ctypes-1.0.2.win32-py2.5-AMD64.msi and comtypes-0.4.2.zip. > > Peter -- Thanks, Thomas - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php ___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users
Re: [comtypes-users] passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)
[EMAIL PROTECTED] schrieb: [passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)] > Seems to stomp memory. I'm not a native english speaker and do not understand what you mean. Also, can you give a description or a code sample to illustrate the problem? Best would be if you can submit a test case. > A work around is to declare the parameter as a POINTER(GUID) instead > of GUID and pass a copy of the GUID instance byref [this should be > what happens under the covers]. I'm not sure if this is a comtypes > or ctypes issue; it likely applies to other "large" datatypes as > well. I'm using python-2.5.2.amd64.msi, > ctypes-1.0.2.win32-py2.5-AMD64.msi and comtypes-0.4.2.zip. > > Peter -- Thanks, Thomas - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php ___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users
[comtypes-users] passing GUIDs by value works on 32-bit python but not 64-bit python (on Vista 64)
Seems to stomp memory. A work around is to declare the parameter as a POINTER(GUID) instead of GUID and pass a copy of the GUID instance byref [this should be what happens under the covers]. I'm not sure if this is a comtypes or ctypes issue; it likely applies to other "large" datatypes as well. I'm using python-2.5.2.amd64.msi, ctypes-1.0.2.win32-py2.5-AMD64.msi and comtypes-0.4.2.zip. Peter- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php___ comtypes-users mailing list comtypes-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/comtypes-users
