Using kevent for signalling user app from kernel

[arrowdodger]

On Thu, Dec 22, 2011 at 10:03 AM, Sushanth Rai <sushanth_rai at yahoo.com>wrote:

> Hi,
>
> I'm planning to use kqueue/kevent mechanism to notify a user application
> from the kernel. Basically I set up a file descriptor for read event from
> the user application by calling kevent(). Now, I would like to wake-up the
> process from within the kernel. The wake-up will happen due to one of the
> internal events (not due to data being available to read). I have access to
> the process structure and vnode corresponding to file descriptor. Is there
> a mechanism available from the kernel to trigger a wakeup and clear the
> kernel break notify message ?
>
> Thanks,
> Sushanth
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Hi. I'm not very experienced in this stuff, but you can try to look at how
EVFILT_USER is handled. Specifically, take a look at what is going on when
this filter is triggered from userland.