xref: /freebsd/contrib/ntp/html/ntptime.html (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html>
3<head>
4<meta http-equiv="content-type" content="text/html;charset=iso-8859-1">
5<meta name="generator" content="HTML Tidy, see www.w3.org">
6<title>ntptime - read and set kernel time variables</title>
7<link href="scripts/style.css" type="text/css" rel="stylesheet">
8</head>
9<body>
10<h3><tt>ntptime</tt> - read and set kernel time variables</h3>
11<img src="pic/pogo5.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/~mills/pictures.html">from <i>Pogo</i>, Walt Kelly</a>
12<p>The turtle has been swimming in the kernel.</p>
13<p>Last update:
14  <!-- #BeginDate format:En2m -->11-Sep-2010  05:55<!-- #EndDate -->
15  UTC</p>
16<br clear="left">
17<hr>
18<h4>Synopsis</h4>
19<tt>ntptime [ -chr ] [ -e <i>est_error</i> ] [ -f <i>frequency</i> ] [ -m <i>max_error</i> ] [ -o <i>offset</i> ] [ -s <i>status</i> ] [ -t <i>time_constant</i>]</tt>
20<h4>Description</h4>
21<p>This program is useful only with special kernels described in the <a href="kern.html">A Kernel Model for Precision Timekeeping</a> page. It reads and displays time-related kernel variables using the <tt>ntp_gettime()</tt> system call. A similar display can be obtained using the <tt>ntpdc</tt> program and <tt>kerninfo</tt> command.</p>
22<h4>Options</h4>
23<dl>
24  <dt><tt>-c</tt></dt>
25  <dd>Display the execution time of <tt>ntptime</tt> itself.</dd>
26  <dt><tt>-e <i>est_error</i></tt></dt>
27  <dd>Specify estimated error, in microseconds.</dd>
28  <dt><tt>-f <i>frequency</i></tt></dt>
29  <dd>Specify frequency offset, in parts per million.</dd>
30  <dt><tt>-h</tt></dt>
31  <dd>Display help information.</dd>
32  <dt><tt>-m <i>max_error</i></tt></dt>
33  <dd>Specify max possible errors, in microseconds.</dd>
34  <dt><tt>-o <i>offset</i></tt></dt>
35  <dd>Specify clock offset, in microseconds.</dd>
36  <dt><tt>-r</tt></dt>
37  <dd>Display Unix and NTP times in raw format.</dd>
38  <dt><tt>-s <i>status</i></tt></dt>
39  <dd>Specify clock status. Better know what you are doing.</dd>
40  <dt><tt>-t <i>time_constant</i></tt></dt>
41  <dd>Specify time constant, an integer in the range 0-10.</dd>
42</dl>
43<hr>
44<script type="text/javascript" language="javascript" src="scripts/footer.txt"></script>
45</body>
46</html>
47