I am trying to use a GPS clock with ntp 4 in -current on a i386
platform. 

1. Configuring ntp.conf with 
pps /dev/gps0 assert hardpps
server 127.127.20.0 prefer

gets me 

ntpd 4.0.99i Tue May  9 00:20:10 EDT 2000 (1)
using kernel phase-lock loop 0001
refclock_ioctl: time_pps_kcbind failed: Bad address
refclock_open: fd 10 ioctl failed: Bad address
configuration of 127.127.20.0 failed

2. I cannot find the kernel code that handles the PPS_IOC_KCBIND
ioctl. It is called from the inline function time_pps_kcbind in
<sys/timepps.h>. According to com.c, PPS_IOC_KCBIND should fail with
ENOTTY rather than EFAULT.

3. Looking through dev/ic/com.c, I find sections of code for the pps
handling ifdef'd with PPS_SYNC, but opt_ntp.h, which defines PPS_SYNC,
is not #included. Doing so generates a number of undeclared PPS_..
symbols. AFAICT, the only calls to the pps interrupt machinery are
made from inside #ifdef PPS_SYNC sections, ie hardpps() is never
called.

Is anyone using ntp refclocks that make use of kernel pps?

-- 
    - aew