When to create CDO in an upper filter

NTDEV
1

Hello there,

My upper filter monitors the start of various device classes (disk drives, modems…) and I want to be able to communicate with it from some user mode application.

I have a doubt about the best way of creating the control device object. I have seen samples that create the CDO the first time the driver attaches to the device, but my problem is that my driver will not always attach to every device, so I don’t want to depend on any device attachment.

So, is it possible to create the CDO during the “first” DriverEntry, and delete it during the “last” Unload?

Thanks folks.

2

You can’t create the ceo in DriverEntry and then be able to unload because of pnp removing out from the last device. We went over this in your previous thread. The answer is the same.

d

dent from a phpne with no keynoard

-----Original Message-----
From: xxxxx@yahoo.es
Sent: August 25, 2010 1:58 AM
To: Windows System Software Devs Interest List
Subject: [ntdev] When to create CDO in an upper filter

Hello there,

My upper filter monitors the start of various device classes (disk drives, modems…) and I want to be able to communicate with it from some user mode application.

I have a doubt about the best way of creating the control device object. I have seen samples that create the CDO the first time the driver attaches to the device, but my problem is that my driver will not always attach to every device, so I don’t want to depend on any device attachment.

So, is it possible to create the CDO during the “first” DriverEntry, and delete it during the “last” Unload?

Thanks folks.

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