2 .\" Copyright (c) 2003 Tom Rhodes
3 .\" All rights reserved.
5 .\" Redistribution and use in source and binary forms, with or without
6 .\" modification, are permitted provided that the following conditions
8 .\" 1. Redistributions of source code must retain the above copyright
9 .\" notice, this list of conditions and the following disclaimer.
10 .\" 2. Redistributions in binary form must reproduce the above copyright
11 .\" notice, this list of conditions and the following disclaimer in the
12 .\" documentation and/or other materials provided with the distribution.
14 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 .\" $FreeBSD: src/lib/libc/sys/ntp_adjtime.2,v 1.1.2.1 2003/04/22 17:31:18 trhodes Exp $
27 .\" $DragonFly: src/lib/libc/sys/ntp_adjtime.2,v 1.5 2008/02/01 21:40:53 swildner Exp $
34 .Nd NTP daemon application interface
41 .Fn ntp_adjtime "struct timex *tp"
45 system call is used as a kernel interface
46 for the Network Time Protocol daemon,
50 structure are interpreted in either
51 microseconds or nanoseconds, according to the state of the
63 system calls can be used to determine which
64 resolution is in use, and to select either one at any time.
65 The resolution selected affects the scaling of certain fields in the
73 is extremely complex and stateful.
74 Users should not attempt modification without first
80 * NTP daemon interface (ntp_adjtime()) - used to discipline CPU clock
81 * oscillator and determine status.
83 * Note: The offset, precision and jitter members are in microseconds if
84 * STA_NANO is zero and nanoseconds if not.
87 unsigned int modes; /* clock mode bits (wo) */
88 long offset; /* time offset (ns/us) (rw) */
89 long freq; /* frequency offset (scaled PPM) (rw) */
90 long maxerror; /* maximum error (us) (rw) */
91 long esterror; /* estimated error (us) (rw) */
92 int status; /* clock status bits (rw) */
93 long constant; /* poll interval (log2 s) (rw) */
94 long precision; /* clock precision (ns/us) (ro) */
95 long tolerance; /* clock frequency tolerance (scaled
98 * The following read-only structure members are implemented
99 * only if the PPS signal discipline is configured in the
100 * kernel. They are included in all configurations to insure
103 long ppsfreq; /* PPS frequency (scaled PPM) (ro) */
104 long jitter; /* PPS jitter (ns/us) (ro) */
105 int shift; /* interval duration (s) (shift) (ro) */
106 long stabil; /* PPS stability (scaled PPM) (ro) */
107 long jitcnt; /* jitter limit exceeded (ro) */
108 long calcnt; /* calibration intervals (ro) */
109 long errcnt; /* calibration errors (ro) */
110 long stbcnt; /* stability limit exceeded (ro) */
114 Upon successful completion,
118 argument with the current clock state.
122 Possible states of the clock are:
124 .Bl -tag -compact -width ".Dv TIME_ERROR"
126 Everything okay, no leap second warning.
128 insert leap second warning.
130 delete leap second warning.
132 Leap second in progress.
134 Leap second has occurred.
136 Clock not synchronized.
141 system call may return
144 does not have sufficient permissions.
147 .Xr ntpd 8 Pq Pa pkgsrc/net/openntpd
149 This manual page was written by
150 .An Tom Rhodes Aq trhodes@FreeBSD.org .