Re: [PATCH] [RFCv2] notify userspace about time changes

Peter Zijlstra
2010-08-19T09:51:42Z

On Wed, 2010-08-18 at 16:53 -0700, Andrew Morton wrote:
>
>
> Such applications might be better served via a wake-me-at-this-time
> syscall instead of a sleep-me-for-this-long syscall. Although such a
> thing is less general.
>
We have timer_create(.clockid = CLOCK_REALTIME) for such things, no?

> > + fd = open("/sys/kernel/time_notify", O_WRONLY);
> > + fdprintf(fd, "%d 1 0 1 1", efd);
>
> why not
>
> sys_time_notify(efd, 1, 0, 1, 1);

And then there is the /dev/time proposal from Plan9:

http://lkml.org/lkml/2009/3/11/363

Their proposal was to add a poll() method to the device which would wake
on every change in time.