[ntp:questions] ntpd connect gpsd shared memory driver

Rob nomail at example.com
Tue Jun 18 20:46:36 UTC 2013

Richard Cagley <rcagley at gmail.com> wrote:
> Does "removing a definition" refer to removing one of the timeservers from
> the ntp.conf file? Presently, I don't have pps support built into my kernel.

I'm sorry, but I am not familiar with it.
I use gpsd+ntpd on a system without pps support.

I think it can be done in two ways (but I am not sure):
1. by using a driver inside ntpd to support a GPS receiver

2. by using some program to tell the kernel where to look for pps pulses.

That program is then probably called somewhere in system startup.
But I don't have any details on that.

What should be clear is that you *cannot* use the ntpd driver for a
GPS receiver and gpsd at the same time.  They would have to share the
data from the serial port.

In fact this is one of the reasons why gpsd exists at all, and why it
has time sync functions.   When you want to use the receiver both for
time sync and position info, the data somehow has to be multiplexed.

(it seems there is some limited function in one of the ntpd GPS drivers
to save the position info somewhere where it can be accessed by other

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