Re: Kernel / Userspace Data Transfer

From: Ross Dickson
Date: Sun Mar 28 2004 - 23:56:42 EST

lml@xxxxxxxxxxxxxxx wrote:
> I have a set of counters in a Kernel module that i want to export to a
> userspace application. I originally decided to use a /proc entry and parse
> the output whenever the userspace application needed this data, however,
> i need more than the 4096 that is allowed in /proc and i'm not too keen
> on parsing large chunks of text anyway.
> What i would like to do is copy these slabs of text from the kernel to my
> userspace application (whenever the application requests it). I've seen the
> 'copy_to_user' function and it looks usefull, but have no idea where to start
> or how to use it :-/
> Can someone provide and example or point me in the right direction? Or is there
> a better place to ask this question?

Here is a good starter on-line reference
Relevant page
or as pdf

There is also mbuff that maps shared memory between kernel and user space.
It is pretty easy to use.

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