Re: Kernelspace to Userspace message passing

[Jan Hudec <bulb@ucw.cz>]

> I have an userspace application running, which communicates to a kernel modules
> using IOCTLs. Now, from time to time, the kernel needs to send a message back to the 
> application. Now one alternative would be that the app polls the kernel using IOCTLs
> to see if any message is waiting. How can I avoid that and send a message directly
> as in a callback or signal?

When you use ioctl, you have to have a file descriptor. It should be possible to
implement poll syscall to work with that descriptor (character device or proc
file).

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                  				- Jan Hudec `Bulb' <bulb@ucw.cz>
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