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Old 08-31-2004, 01:37 AM   #1
snigglyfox
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Registered: Apr 2004
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User/Kernel Space Comms under Redhat 9.0


Howdy all,

I'm looking for some suggestions on how I can implement a virutal driver for Redhat 9.0. I'd like to replace the existing module character driver with one which will emulate the original whilst not requiring the device and allow the user to simulate different device contingencies. Ideally I'd like the driver to pipe all read and write function calls to a user space daemon.

I don't seem to be able to find any way to get data into user space from my driver outside the sanctioned read/write functions. Any ideas guys?

Rich
 
Old 08-31-2004, 11:44 AM   #2
cracauer
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People rarely do that. The problem is that there is one userlevel process using this driver. When the other userlevel process (the one behind the driver) screws up, then the original process is blocked in the systemcall forever.

But if somebody knows an example (not a filesystem, a char driver) I would be interested, too.
 
Old 09-06-2004, 06:07 PM   #3
snigglyfox
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By jove I've got it! Use the proc file system...

http://www.kernelnewbies.org/documen...ocfsguide.html
 
Old 09-07-2004, 05:24 AM   #4
nukkel
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You mean registering a file there and then intercepting all read(2) syscalls to that file, generating the "contents" on the fly? Yeah, that's a nice idea...
 
  


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