freebsd/contrib/ntp/util/README

README file for directory ./util of the NTP Version 4 distribution

This directory contains the sources for the various utility programs.
See the README and RELNOTES files in the parent directory for directions
on how to make and install these programs.

The ntptime.c program checks the kernel configuration for the NTP user
interface syscalls ntp_gettime() and ntp_adjtime().  If present, the
current timekeeping data are displayed.  If not, a dissapointment is
displayed.  See the kernel page file in the HTML documentation in
distribution for further details. ntptime will be built be if configure
believes your system can use it.

The jitter.c program can be used to determine the timing jitter due to
the operating system in a gettimeofday() call.  For most systems the
dominant contribution to the jitter budget is the period of the hardware
interrupt, usually in the range 10 us-1 ms.  For those systems with
microsecond counters, such as recent Sun and certain HP and DEC systems,
the jitter is dominated only by the operating system.

The timetrim.c program can be used with SGI machines to implement a
scheme to discipline the hardware clock frequency.  See the source code
for further information.

The byteorder.c and longsize.c programs are used during the configuration
process to determine the byte order (little or big endian) and longword
size (32 or 64 bits).  See the configure scripts for further details.

The testrs6000.c program is used for testing purposes with the IBM
RS/6000 AIX machines. Bill Jones <jones@chpc.utexas.edu> reports:
"I could not get a tickadj of less then 40 us to work on a RS6000.
If you set it less then 40 us do so at your own risk!"

The tickadj.c program can be used to read and set various kernel
parameters affecting NTP operations. See the tickadj page in the HTML
documentation for further details.  tickadj will be built if configure
believes your system can use it.