I am loading a simple minifilter on Win7 free build which loads fine (i.e. no errors) but I do not see any of my DbgPrint messages. I am using DebugView on the test system and I do not see any messages at all, either from my driver or not. How can I tell if my driver got loaded into the file system at the correct altitude? Why am I not seeing any debug messages?
DbgPrint : http://www.osronline.com/article.cfm?id=295
To see the altitude you can use “!fltkd.filters” in the debugger or
“fltmc.exe” on an elevated command prompt on the machine where your
minifilter is installed.
Thanks,
Alex.
awesome thanks. i can see the altitude but num instances = 0. i did not get any error messages when installing so i’m not sure what would prevent an instance. any ideas?
Just loading a minifilter doesn’t necessarily create any instances.
Do you have automatic attachment enabled (Flags in the INF files is 0) ? See
article on “Creating an INF File for a Minifilter Driver” on MSDN (currently
at http://msdn.microsoft.com/en-us/library/ff540045(v=vs.85).aspx). If not
(and Flags is 1) then you need to manually attach the filter.
Fltmc should work (try fltmc help and then fltmc attach) if you want to
attach to a specific volume manually.
Thanks,
Alex.
thank you! clearly i am a newbie. i have done some linux device driver work but this is my first foray into windows.
Not to discourage you, but you’ve picked a challenging way to learn Windows drivers - file system mini-filters are difficult to write properly on Windows.
With that said, best of luck - once you’ve figured these out, the rest of it won’t seem so hard.
Tony
OSR
Yeah, I’ve got some basics working now so I feel pretty good for today at least.
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