If you are compiling under FreeBSD and see messages in the syslogs thatindicate that the ntpd process is trying to use unavailable sched_calls, it means you are running a kernel that does not have the POSIXscheduling calls enabled.You have two choices:- Ignore the messages- Generate a new kernel, where the kernel configuration file contains  the lines:  options		"P1003_1B"  options		"_KPOSIX_PRIORITY_SCHEDULING"  options		"_KPOSIX_VERSION=199309L"