[python-win32] USB Insertion Extrinsic Event exists?

[Tim Golden]

On 12/02/2010 16:58, Chris Jesse wrote:
> So it turns out that my description of the task was lacking in one
> simple, but critical, observation. We use removable media, usually a compact
> flash card, plugged into a USB adapter drive. The events get triggered for
> my pen drive, but when the compact flash card is inserted I get nothing -
> probably because the device is already plugged in.

OK; just tried it and I see what you mean. In my case, I'm using
one of those card readers with four different-sized slots. It
"pre-registers" as four drives so you don't get any further device
change events. (I assume this is comparable to what you're doing...)

All I can suggest is that you watch the Win32_DiskDrive instances
with an InterfaceType of "USB" for a modification event and check
whether the MediaLoaded has changed. Something like this:

<code>
import wmi

c = wmi.WMI ()
watcher = c.Win32_DiskDrive.watch_for (InterfaceType="USB")

while True:
   try:
     disk = watcher (timeout_ms=10000)
     print disk
   except wmi.x_wmi_timed_out:
     pass

</code>

If you know which device id will always be firing (eg the only
slot I can use is PHYSICALDEVICE3 then you can build that into
the query.

> There's an interesting document attached which shows some potential
>C++ code; but I'm in a little out of my depth here - "help"!

About half of that is basically the code I posted here:

http://local.timgolden.me.uk/python/win32_how_do_i/detect-device-insertion.html

The other half deals with the case where you want to use this
sort of technique but where you're in a service or otherwise
don't have a top-level window. If the WMI stuff doesn't work
for you and you need this kind of thing (and don't have/want
a top-level window) then we can try to run something up on
the basis of the article.

TJG