[LinuxPPS] PPS next steps...

[Rodolfo Giometti]

On Fri, Feb 06, 2009 at 09:22:31AM -0500, George Spelvin wrote:
> I need to test things like the poll function and fasync.
> The patches I posted run ntpd just fine (x86_64, at least), but
> that doesn't test the more obscure stuff.

The fasync part should be discussed well...

> Given a working poll function, it would be nice to change the kernel
> API to handle the timeout in user space using poll() or select() and
> simplfy the kernel fetch IOCTL.

I agree but keep in mind RFC's PPS API, I think is totally useless
doing something Linux specific only.

> I'm also thinking about a text form to be delivered when
> reading from the file.  the main problem is that the format in
> /sys/class/pps/pps%d/{assert,clear} provides no way to distinguish assert
> from clear edges.  Maybe a leading sign on the sequence number?

Yes.

> Or just a Plan 9 style whitespace-separated line.
> assert <seq> <time>.<frac>
> clear <seq> <time>.<frac>

No. you cannot put spaces into sysfs files.

Ciao,

Rodolfo

-- 

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