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Old 04-01-2013, 11:31 AM   #1
ratbat
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Sending data from kernel to user space


What is the simplest way to send data from kernel to user-space?
Is it possible to use the read system call in the user space program?
If yes, please explain how to do so.

Thanks!!
 
Old 04-01-2013, 12:57 PM   #2
PrinceCruise
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Hi,
What are you exactly trying to achieve? May be these system calls are what you looking for:-

Quote:
copy_to_user() and copy_from_user()
You'll get a ton load of information on this in web.

Regards.
 
Old 04-02-2013, 02:51 AM   #3
ratbat
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Question

Hi,
Thanks for your help!

I want the user to read data only when something is written by the kernel module. Is it possible to achieve this kind of synchronisation between the user-space program and the kernel module?
 
Old 04-02-2013, 03:33 AM   #4
PrinceCruise
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Well, that's possible and that's exactly where I'd use the above mentioned system calls. In the kernel module, in the reader part, use the call copy_to_user() and in the writer, use copy_from_user().

Regards.
 
  


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