My minifilter keeps track of changes to specified folders. I’m planning to have these folders specified in a configuration file. For now, I’m trying to avoid a user mode program to send these paths to the filter - the filter itself will read the configuration file.
This works as long as I stick to paths with the full device names. But if I want to use drive letters I don’t see a easy way in minifilter to convert these drive letters to device names. Looks like MOUNTMGR ioctls can help in this conversion. My question is, is it save to use MOUNTMGR ioctls in a minifilter?
Sajeev
Please, don’t send the same letter for me.
Thank you very much. 
On 5/27/07, xxxxx@yahoo.com wrote:
>
> My minifilter keeps track of changes to specified folders. I’m planning to
> have these folders specified in a configuration file. For now, I’m trying to
> avoid a user mode program to send these paths to the filter - the filter
> itself will read the configuration file.
>
> This works as long as I stick to paths with the full device names. But if
> I want to use drive letters I don’t see a easy way in minifilter to convert
> these drive letters to device names. Looks like MOUNTMGR ioctls can help in
> this conversion. My question is, is it save to use MOUNTMGR ioctls in a
> minifilter?
>
> Sajeev
>
> —
> Questions? First check the IFS FAQ at
> https://www.osronline.com/article.cfm?id=17
>
> You are currently subscribed to ntfsd as: xxxxx@gmail.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com
>
Sajeev,
If you use drive letters in your filter driver you are going to run into
issues. The common case is fast user switching where a given volume
under one user is mapped to c: whereas under the second user it is
mapped to d:. Essentially it is a many to one relation. If you can, stay
away from drive letters, instead use the volume GUID names which is
always the same for a volume.
Maybe with the application which builds the configuration file, it would
convert a drive letter to volume GUID name.
Pete
Kernel Drivers
Windows File System and Device Driver Consulting
www.KernelDrivers.com
(303)546-0300
xxxxx@yahoo.com wrote:
My minifilter keeps track of changes to specified folders. I’m planning to have these folders specified in a configuration file. For now, I’m trying to avoid a user mode program to send these paths to the filter - the filter itself will read the configuration file.
This works as long as I stick to paths with the full device names. But if I want to use drive letters I don’t see a easy way in minifilter to convert these drive letters to device names. Looks like MOUNTMGR ioctls can help in this conversion. My question is, is it save to use MOUNTMGR ioctls in a minifilter?
Sajeev
Questions? First check the IFS FAQ at https://www.osronline.com/article.cfm?id=17
You are currently subscribed to ntfsd as: xxxxx@kerneldrivers.com
To unsubscribe send a blank email to xxxxx@lists.osr.com
A technique that I like to use is to establish some sort of IOCTL/FSCTL
for the application to extract a name that has meaning to my filter.
Thus, the application can open using the name *it* recognizes and I can
give it a name that *I* recognize.
In this way, I can eliminate a common source of ambiguity.
Tony
Tony Mason
Consulting Partner
OSR Open Systems Resources, Inc.
http://www.osr.com
Hi,
If I understand correctly, you are saying here that on a particular
system with users UserA and UserB, we can have a mapping like:
for UserA: \DosDevices\K: ==> \Device\HarddiskVolume8
for UserB: \DosDevices\K: ==> \Device\HarddiskVolume8
in the same time? (for example during fast user switching)
Could you please tell me, how to achieve this? AFAIK the drive letter
mappings are stored in HKLM\SYSTEM\MountedDevices, and if I am not
wrong, this is not a per-user key. What am I missing? Does the standard
MS tool (Admin Tools -> Disk Management) allow us to set up such drive
letter mappings?
thank you very much,
Sandor LUKACS
Virus Analyst, SOFTWIN
If you use drive letters in your filter driver you are going to run
into issues. The common case is fast user switching where a given
volume under one user is mapped to c: whereas under the second user it
is mapped to d:. Essentially it is a many to one relation. If you can,
stay away from drive letters, instead use the volume GUID names which
is always the same for a volume.
Maybe with the application which builds the configuration file, it
would convert a drive letter to volume GUID name.
Pete