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Python library - WMI.py RegistryValueChangeEvent

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  Python library - WMI.py RegistryValueChangeEvent Khyati <shrivastavkhyati@gmail.com> - 2015-04-06 15:02 -0700
    Re: Python library - WMI.py RegistryValueChangeEvent Chris Angelico <rosuav@gmail.com> - 2015-04-07 09:49 +1000
      Re: Python library - WMI.py RegistryValueChangeEvent Khyati <shrivastavkhyati@gmail.com> - 2015-04-07 07:15 -0700
        Re: Python library - WMI.py RegistryValueChangeEvent Chris Angelico <rosuav@gmail.com> - 2015-04-08 00:31 +1000
          Re: Python library - WMI.py RegistryValueChangeEvent Khyati <shrivastavkhyati@gmail.com> - 2015-04-07 07:35 -0700
            Re: Python library - WMI.py RegistryValueChangeEvent Tim Golden <mail@timgolden.me.uk> - 2015-04-07 15:52 +0100
            Re: Python library - WMI.py RegistryValueChangeEvent Tim Golden <mail@timgolden.me.uk> - 2015-04-07 16:18 +0100
              Re: Python library - WMI.py RegistryValueChangeEvent Khyati <shrivastavkhyati@gmail.com> - 2015-04-07 08:30 -0700
                Re: Python library - WMI.py RegistryValueChangeEvent Khyati <shrivastavkhyati@gmail.com> - 2015-04-07 09:00 -0700

#88548 — Python library - WMI.py RegistryValueChangeEvent

I have a question about RegistryValueChangeEvent that I have not been able to find an answer to on the internet so far. I would appreciate any help since I have already spent a lot of time finding any material that explains this:

What I am trying to do: 
- create an event when a value for a registry key changes

How I am doing it:
>raw_wql = "SELECT * FROM RegistryValueChangeEvent WHERE Hive='HKEY_LOCAL_MACHINE' AND KeyPath='Software\\\\Temp' AND ValueName='Name\'"
>watcher = c.watch_for(raw_wql=raw_wql,wmi_class = "__ExtrinsicEvent")
>while TRUE:
>    process_created = watcher()

Problem:
the _wmi_event object returned is not coming back as Extrinsic event - 
So, in wmi.py, in class _wmi_watcher:
   "self.is_extrinsic" returns false and I get an exception from the else part - [line 1186 - 1195]

What I need 
- Any reference/idea/explanation on => why does RegistryValueChangeEvent returns as a Non-Extrinsic  event? even though it has been derived from __ExtrinsicEvent

Other information:
Running on Windows 8 64 Bit 
>>> platform.machine()
'AMD64'
>>> platform.architecture()
('64bit', 'WindowsPE')
>>> platform.python_version()
'2.7.8'
>>> platform.python_implementation()
'CPython'

Using WMI-1.4.9.win32 - downloaded via PIP
pywin32-219.win-amd64-py2.7

Thanks

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#88550

On Tue, Apr 7, 2015 at 8:02 AM, Khyati <shrivastavkhyati@gmail.com> wrote:
> I have a question about RegistryValueChangeEvent that I have not been able to find an answer to on the internet so far. I would appreciate any help since I have already spent a lot of time finding any material that explains this:
>
> What I am trying to do:
> - create an event when a value for a registry key changes

Thanks for being clear about this part! Unfortunately, there are a few
other parts that aren't clear yet, so hopefully you can expand on your
question a bit.

> How I am doing it:
>>raw_wql = "SELECT * FROM RegistryValueChangeEvent WHERE Hive='HKEY_LOCAL_MACHINE' AND KeyPath='Software\\\\Temp' AND ValueName='Name\'"

Tip: Try adding "print(raw_wql)" just underneath this line, to see if
you're getting back what you really want. The backslash at the end of
ValueName is not currently doing anything.

>>watcher = c.watch_for(raw_wql=raw_wql,wmi_class = "__ExtrinsicEvent")
>>while TRUE:
>>    process_created = watcher()

This code isn't complete. Can you post a complete (and minimal)
example piece of code?

> Problem:
> the _wmi_event object returned is not coming back as Extrinsic event -
> So, in wmi.py, in class _wmi_watcher:
>    "self.is_extrinsic" returns false and I get an exception from the else part - [line 1186 - 1195]

It'd help hugely if you could post the entire traceback here - what
exception you're getting, and the exact lines that produce it.

> What I need
> - Any reference/idea/explanation on => why does RegistryValueChangeEvent returns as a Non-Extrinsic  event? even though it has been derived from __ExtrinsicEvent
>
> Other information:
> Running on Windows 8 64 Bit
>>>> platform.machine()
> 'AMD64'
>>>> platform.architecture()
> ('64bit', 'WindowsPE')
>>>> platform.python_version()
> '2.7.8'
>>>> platform.python_implementation()
> 'CPython'
>
> Using WMI-1.4.9.win32 - downloaded via PIP
> pywin32-219.win-amd64-py2.7

Just for reference, this is a general Python discussion list. Lots of
us won't know specific libraries, so all we can offer is fairly
general information. If you can't get the help you need here, you may
do better to look for more specific help about this module.

All the best!

ChrisA

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#88577

Thanks for taking a look, Chris.
The error trace:
traceback (most recent call last):
 File "MonitorRegistry.py", line 18, in <module>
   process_created = watcher()
 File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
   handle_com_error ()
 File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
   raise klass (com_error=err)
_wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>

when I debugged this is the module that throws the exception:
wmi.py [Line 1178-1195]
 def __call__ (self, timeout_ms=-1):
    """When called, return the instance which caused the event. Supports
     timeout in milliseconds (defaulting to infinite). If the watcher
     times out, :exc:`x_wmi_timed_out` is raised. This makes it easy to support
     watching for multiple objects.
    """
    try:
      event = self.wmi_event.NextEvent (timeout_ms)
      if self.is_extrinsic:
        return _wmi_event (event, None, self.fields)
      else:
        return _wmi_event (
          event.Properties_ ("TargetInstance").Value,
          _wmi_object (event, property_map=self._event_property_map),
          self.fields
        )
    except pywintypes.com_error:
      handle_com_error ()

self.is_extrinsic returns false and event.Properties_("TargetInstance").Value throws the exception

Here is the entire(minimal) code:
import wmi
import _winreg
c = wmi.WMI ()
raw_wql = "SELECT * FROM RegistryValueChangeEvent WHERE Hive='HKEY_LOCAL_MACHINE' AND KeyPath='Software\\\\Temp' AND ValueName='Name'"
print raw_wql
watcher = c.watch_for(raw_wql=raw_wql,wmi_class = "__ExtrinsicEvent")
while True:
  try:
	process_created = watcher()
	print 'value changed'


I have already emailed - Tim Golden <mail@timgolden.me.uk>
Any other group that I can reach to?


Thanks
Khyati

On Monday, April 6, 2015 at 7:50:37 PM UTC-4, Chris Angelico wrote:
> On Tue, Apr 7, 2015 at 8:02 AM, Khyati <shrivastavkhyati@gmail.com> wrote:
> > I have a question about RegistryValueChangeEvent that I have not been able to find an answer to on the internet so far. I would appreciate any help since I have already spent a lot of time finding any material that explains this:
> >
> > What I am trying to do:
> > - create an event when a value for a registry key changes
> 
> Thanks for being clear about this part! Unfortunately, there are a few
> other parts that aren't clear yet, so hopefully you can expand on your
> question a bit.
> 
> > How I am doing it:
> >>raw_wql = "SELECT * FROM RegistryValueChangeEvent WHERE Hive='HKEY_LOCAL_MACHINE' AND KeyPath='Software\\\\Temp' AND ValueName='Name\'"
> 
> Tip: Try adding "print(raw_wql)" just underneath this line, to see if
> you're getting back what you really want. The backslash at the end of
> ValueName is not currently doing anything.
> 
> >>watcher = c.watch_for(raw_wql=raw_wql,wmi_class = "__ExtrinsicEvent")
> >>while TRUE:
> >>    process_created = watcher()
> 
> This code isn't complete. Can you post a complete (and minimal)
> example piece of code?
> 
> > Problem:
> > the _wmi_event object returned is not coming back as Extrinsic event -
> > So, in wmi.py, in class _wmi_watcher:
> >    "self.is_extrinsic" returns false and I get an exception from the else part - [line 1186 - 1195]
> 
> It'd help hugely if you could post the entire traceback here - what
> exception you're getting, and the exact lines that produce it.
> 
> > What I need
> > - Any reference/idea/explanation on => why does RegistryValueChangeEvent returns as a Non-Extrinsic  event? even though it has been derived from __ExtrinsicEvent
> >
> > Other information:
> > Running on Windows 8 64 Bit
> >>>> platform.machine()
> > 'AMD64'
> >>>> platform.architecture()
> > ('64bit', 'WindowsPE')
> >>>> platform.python_version()
> > '2.7.8'
> >>>> platform.python_implementation()
> > 'CPython'
> >
> > Using WMI-1.4.9.win32 - downloaded via PIP
> > pywin32-219.win-amd64-py2.7
> 
> Just for reference, this is a general Python discussion list. Lots of
> us won't know specific libraries, so all we can offer is fairly
> general information. If you can't get the help you need here, you may
> do better to look for more specific help about this module.
> 
> All the best!
> 
> ChrisA

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#88580

On Wed, Apr 8, 2015 at 12:15 AM, Khyati <shrivastavkhyati@gmail.com> wrote:
> Thanks for taking a look, Chris.
> The error trace:
> traceback (most recent call last):
>  File "MonitorRegistry.py", line 18, in <module>
>    process_created = watcher()
>  File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
>    handle_com_error ()
>  File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
>    raise klass (com_error=err)
> _wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>

It looks to me like this is a thin wrapper around the underlying API
call, and you're getting back an error from the lower-level services.
The way this reads, there might well not be an
HKLM\Software\Temp\Name; maybe the ValueName is what's wrong here?

Someone somewhere knows more than I do, but if you can't find that
someone here on python-list, you might be able to find some help on
Stack Overflow or another mailing list, from people who know how to do
this kind of thing in a different language. You'd have to translate
their suggestions back into Python, but when the wrappers are thin
enough, that's usually not too hard.

ChrisA

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#88583

On Tuesday, April 7, 2015 at 10:31:47 AM UTC-4, Chris Angelico wrote:
> On Wed, Apr 8, 2015 at 12:15 AM, Khyati wrote:
> > Thanks for taking a look, Chris.
> > The error trace:
> > traceback (most recent call last):
> >  File "MonitorRegistry.py", line 18, in <module>
> >    process_created = watcher()
> >  File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
> >    handle_com_error ()
> >  File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
> >    raise klass (com_error=err)
> > _wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>
> 
> It looks to me like this is a thin wrapper around the underlying API
> call, and you're getting back an error from the lower-level services.
> The way this reads, there might well not be an
> HKLM\Software\Temp\Name; maybe the ValueName is what's wrong here?
> 
> Someone somewhere knows more than I do, but if you can't find that
> someone here on python-list, you might be able to find some help on
> Stack Overflow or another mailing list, from people who know how to do
> this kind of thing in a different language. You'd have to translate
> their suggestions back into Python, but when the wrappers are thin
> enough, that's usually not too hard.
> 
> ChrisA

HKLM\Software\Temp\Name exists since the event is caught correctly only when I change that key.
i'll keep looking :)

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#88586

On 07/04/2015 15:35, Khyati wrote:
> On Tuesday, April 7, 2015 at 10:31:47 AM UTC-4, Chris Angelico wrote:
>> On Wed, Apr 8, 2015 at 12:15 AM, Khyati wrote:
>>> Thanks for taking a look, Chris.
>>> The error trace:
>>> traceback (most recent call last):
>>>  File "MonitorRegistry.py", line 18, in <module>
>>>    process_created = watcher()
>>>  File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
>>>    handle_com_error ()
>>>  File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
>>>    raise klass (com_error=err)
>>> _wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>
>>
>> It looks to me like this is a thin wrapper around the underlying API
>> call, and you're getting back an error from the lower-level services.
>> The way this reads, there might well not be an
>> HKLM\Software\Temp\Name; maybe the ValueName is what's wrong here?
>>
>> Someone somewhere knows more than I do, but if you can't find that
>> someone here on python-list, you might be able to find some help on
>> Stack Overflow or another mailing list, from people who know how to do
>> this kind of thing in a different language. You'd have to translate
>> their suggestions back into Python, but when the wrappers are thin
>> enough, that's usually not too hard.
>>
>> ChrisA
> 
> HKLM\Software\Temp\Name exists since the event is caught correctly only when I change that key.
> i'll keep looking :)
> 

Hi, Khyati.

Unfortunately, extrinsic events don't come with much information. As you
can see from the MSDN description:

https://msdn.microsoft.com/en-us/library/aa390355%28v=vs.85%29.aspx

they're not linked to WMI objects internally (which the intrinsic events
are) so all they can do is echo back to you details of what changed --
which will usually be the thing you were asking about in the first place!

So the Python wrapper doesn't receive any TargetInstance because it's
not a *WMI* event as such, linked to a WMI object; rather, it's an
external event which has provided a hook for WMI to hang on to.

In this specific case, you could use the WMI Registry provider to pick
up the current value of that registry value, but that wouldn't tell you
what was there before or anything else. In another case, the event might
be about some entirely external system -- such as the
SecurityViolationEvent in the MSDN example -- which provides no WMI
interface beyond the event itself.

Feel free to ask more, either on this list or on the win32-specific
Python list:

https://mail.python.org/mailman/listinfo/python-win32

(I'm not often free to answer questions so best to use the public forums
where more people will be able to help).

TJG

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#88591

On 07/04/2015 15:52, Tim Golden wrote:
> On 07/04/2015 15:35, Khyati wrote:
>> On Tuesday, April 7, 2015 at 10:31:47 AM UTC-4, Chris Angelico wrote:
>>> On Wed, Apr 8, 2015 at 12:15 AM, Khyati wrote:
>>>> Thanks for taking a look, Chris.
>>>> The error trace:
>>>> traceback (most recent call last):
>>>>  File "MonitorRegistry.py", line 18, in <module>
>>>>    process_created = watcher()
>>>>  File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
>>>>    handle_com_error ()
>>>>  File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
>>>>    raise klass (com_error=err)
>>>> _wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>
>>>
>>> It looks to me like this is a thin wrapper around the underlying API
>>> call, and you're getting back an error from the lower-level services.
>>> The way this reads, there might well not be an
>>> HKLM\Software\Temp\Name; maybe the ValueName is what's wrong here?
>>>
>>> Someone somewhere knows more than I do, but if you can't find that
>>> someone here on python-list, you might be able to find some help on
>>> Stack Overflow or another mailing list, from people who know how to do
>>> this kind of thing in a different language. You'd have to translate
>>> their suggestions back into Python, but when the wrappers are thin
>>> enough, that's usually not too hard.
>>>
>>> ChrisA
>>
>> HKLM\Software\Temp\Name exists since the event is caught correctly only when I change that key.
>> i'll keep looking :)
>>
> 
> Hi, Khyati.
> 
> Unfortunately, extrinsic events don't come with much information. As you
> can see from the MSDN description:
> 
> https://msdn.microsoft.com/en-us/library/aa390355%28v=vs.85%29.aspx
> 
> they're not linked to WMI objects internally (which the intrinsic events
> are) so all they can do is echo back to you details of what changed --
> which will usually be the thing you were asking about in the first place!
> 
> So the Python wrapper doesn't receive any TargetInstance because it's
> not a *WMI* event as such, linked to a WMI object; rather, it's an
> external event which has provided a hook for WMI to hang on to.
> 
> In this specific case, you could use the WMI Registry provider to pick
> up the current value of that registry value, but that wouldn't tell you
> what was there before or anything else. In another case, the event might
> be about some entirely external system -- such as the
> SecurityViolationEvent in the MSDN example -- which provides no WMI
> interface beyond the event itself.
> 
> Feel free to ask more, either on this list or on the win32-specific
> Python list:
> 
> https://mail.python.org/mailman/listinfo/python-win32
> 
> (I'm not often free to answer questions so best to use the public forums
> where more people will be able to help).


Forgot to say: you can simplify your code a little as well:

<code>
import wmi

c = wmi.WMI(namespace="root/default")
watcher = c.RegistryValueChangeEvent(Hive="HKEY_LOCAL_MACHINE",
KeyPath=r"Software\\Temp", ValueName="Name")

event = watcher()

</code>

TJG

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#88593

Thanks TJG for your reply. 
I guess at this point the question is why is the event not returned to wmi as Extrinsic. May be I should explicitly initialize the class _wmi_watcher and set self.is_extrinsic = True?


Thanks
Khyati

On Tuesday, April 7, 2015 at 11:18:39 AM UTC-4, Tim Golden wrote:
> On 07/04/2015 15:52, Tim Golden wrote:
> > On 07/04/2015 15:35, Khyati wrote:
> >> On Tuesday, April 7, 2015 at 10:31:47 AM UTC-4, Chris Angelico wrote:
> >>> On Wed, Apr 8, 2015 at 12:15 AM, Khyati wrote:
> >>>> Thanks for taking a look, Chris.
> >>>> The error trace:
> >>>> traceback (most recent call last):
> >>>>  File "MonitorRegistry.py", line 18, in <module>
> >>>>    process_created = watcher()
> >>>>  File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
> >>>>    handle_com_error ()
> >>>>  File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
> >>>>    raise klass (com_error=err)
> >>>> _wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>
> >>>
> >>> It looks to me like this is a thin wrapper around the underlying API
> >>> call, and you're getting back an error from the lower-level services.
> >>> The way this reads, there might well not be an
> >>> HKLM\Software\Temp\Name; maybe the ValueName is what's wrong here?
> >>>
> >>> Someone somewhere knows more than I do, but if you can't find that
> >>> someone here on python-list, you might be able to find some help on
> >>> Stack Overflow or another mailing list, from people who know how to do
> >>> this kind of thing in a different language. You'd have to translate
> >>> their suggestions back into Python, but when the wrappers are thin
> >>> enough, that's usually not too hard.
> >>>
> >>> ChrisA
> >>
> >> HKLM\Software\Temp\Name exists since the event is caught correctly only when I change that key.
> >> i'll keep looking :)
> >>
> > 
> > Hi, Khyati.
> > 
> > Unfortunately, extrinsic events don't come with much information. As you
> > can see from the MSDN description:
> > 
> > https://msdn.microsoft.com/en-us/library/aa390355%28v=vs.85%29.aspx
> > 
> > they're not linked to WMI objects internally (which the intrinsic events
> > are) so all they can do is echo back to you details of what changed --
> > which will usually be the thing you were asking about in the first place!
> > 
> > So the Python wrapper doesn't receive any TargetInstance because it's
> > not a *WMI* event as such, linked to a WMI object; rather, it's an
> > external event which has provided a hook for WMI to hang on to.
> > 
> > In this specific case, you could use the WMI Registry provider to pick
> > up the current value of that registry value, but that wouldn't tell you
> > what was there before or anything else. In another case, the event might
> > be about some entirely external system -- such as the
> > SecurityViolationEvent in the MSDN example -- which provides no WMI
> > interface beyond the event itself.
> > 
> > Feel free to ask more, either on this list or on the win32-specific
> > Python list:
> > 
> > https://mail.python.org/mailman/listinfo/python-win32
> > 
> > (I'm not often free to answer questions so best to use the public forums
> > where more people will be able to help).
> 
> 
> Forgot to say: you can simplify your code a little as well:
> 
> <code>
> import wmi
> 
> c = wmi.WMI(namespace="root/default")
> watcher = c.RegistryValueChangeEvent(Hive="HKEY_LOCAL_MACHINE",
> KeyPath=r"Software\\Temp", ValueName="Name")
> 
> event = watcher()
> 
> </code>
> 
> TJG

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#88600

Resolved:
watcher = c.watch_for(raw_wql=raw_wql,wmi_class = "RegistryValueChangeEvent")
is the right way - instead of wmi_class = __ExtrinsicEvent

Thanks, everyone.


On Tuesday, April 7, 2015 at 11:30:33 AM UTC-4, Khyati wrote:
> Thanks TJG for your reply. 
> I guess at this point the question is why is the event not returned to wmi as Extrinsic. May be I should explicitly initialize the class _wmi_watcher and set self.is_extrinsic = True?
> 
> 
> Thanks
> Khyati
> 
> On Tuesday, April 7, 2015 at 11:18:39 AM UTC-4, Tim Golden wrote:
> > On 07/04/2015 15:52, Tim Golden wrote:
> > > On 07/04/2015 15:35, Khyati wrote:
> > >> On Tuesday, April 7, 2015 at 10:31:47 AM UTC-4, Chris Angelico wrote:
> > >>> On Wed, Apr 8, 2015 at 12:15 AM, Khyati wrote:
> > >>>> Thanks for taking a look, Chris.
> > >>>> The error trace:
> > >>>> traceback (most recent call last):
> > >>>>  File "MonitorRegistry.py", line 18, in <module>
> > >>>>    process_created = watcher()
> > >>>>  File "C:\Python27\lib\site-packages\wmi.py", line 1195, in __call__
> > >>>>    handle_com_error ()
> > >>>>  File "C:\Python27\lib\site-packages\wmi.py", line 241, in handle_com_error
> > >>>>    raise klass (com_error=err)
> > >>>> _wmi: <x_wmi: Unexpected COM Error (-2147352567, 'Exception occurred.', (0, u'SWbemPropertySet', u'Not found ', None, 0, -2147217406), None)>
> > >>>
> > >>> It looks to me like this is a thin wrapper around the underlying API
> > >>> call, and you're getting back an error from the lower-level services.
> > >>> The way this reads, there might well not be an
> > >>> HKLM\Software\Temp\Name; maybe the ValueName is what's wrong here?
> > >>>
> > >>> Someone somewhere knows more than I do, but if you can't find that
> > >>> someone here on python-list, you might be able to find some help on
> > >>> Stack Overflow or another mailing list, from people who know how to do
> > >>> this kind of thing in a different language. You'd have to translate
> > >>> their suggestions back into Python, but when the wrappers are thin
> > >>> enough, that's usually not too hard.
> > >>>
> > >>> ChrisA
> > >>
> > >> HKLM\Software\Temp\Name exists since the event is caught correctly only when I change that key.
> > >> i'll keep looking :)
> > >>
> > > 
> > > Hi, Khyati.
> > > 
> > > Unfortunately, extrinsic events don't come with much information. As you
> > > can see from the MSDN description:
> > > 
> > > https://msdn.microsoft.com/en-us/library/aa390355%28v=vs.85%29.aspx
> > > 
> > > they're not linked to WMI objects internally (which the intrinsic events
> > > are) so all they can do is echo back to you details of what changed --
> > > which will usually be the thing you were asking about in the first place!
> > > 
> > > So the Python wrapper doesn't receive any TargetInstance because it's
> > > not a *WMI* event as such, linked to a WMI object; rather, it's an
> > > external event which has provided a hook for WMI to hang on to.
> > > 
> > > In this specific case, you could use the WMI Registry provider to pick
> > > up the current value of that registry value, but that wouldn't tell you
> > > what was there before or anything else. In another case, the event might
> > > be about some entirely external system -- such as the
> > > SecurityViolationEvent in the MSDN example -- which provides no WMI
> > > interface beyond the event itself.
> > > 
> > > Feel free to ask more, either on this list or on the win32-specific
> > > Python list:
> > > 
> > > https://mail.python.org/mailman/listinfo/python-win32
> > > 
> > > (I'm not often free to answer questions so best to use the public forums
> > > where more people will be able to help).
> > 
> > 
> > Forgot to say: you can simplify your code a little as well:
> > 
> > <code>
> > import wmi
> > 
> > c = wmi.WMI(namespace="root/default")
> > watcher = c.RegistryValueChangeEvent(Hive="HKEY_LOCAL_MACHINE",
> > KeyPath=r"Software\\Temp", ValueName="Name")
> > 
> > event = watcher()
> > 
> > </code>
> > 
> > TJG

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