[Linuxptp-users] clock_nanosleep on /dev/ptpX (2022)

[todd f. <tod...@gm...>]

Hello,

I found a message from 2014 from someone trying to do exactly what I
am trying to do (sleep against the ptp clock).

fd = open(/dev/ptp0)
ptp = FD_TO_CLOCKID(fd)
clock_nanosleep(ptp, TIMER_ABSTIME, ...) // returns ENOTSUPP

I gather from this message that such support hadn't been implemented in 2014.

https://www.mail-archive.com/lin...@li.../msg00074.html

I gather from the ENOTSUPP return that it's also not implemented
today. I'm running linux 5.19.7. Just wanted confirmation on that
point?

Briefly about my usecase; synchronized music playback across multiple
devices which are using the same ptp GM clock source.

I could run phc2sys on these hosts and then sleep against
CLOCK_MONOTONIC. But I had wanted to avoid that, simply because some
of the devices (desktop pcs) are being used for things other than this
specific application, and I'd not like to takeover the systemwide
clock.

-Todd