html/ntptime.htm


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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
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<meta name="generator" content="HTML Tidy, see www.w3.org">
<title>ntptime - read kernel time variables</title>
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<h3><tt>ntptime</tt> - read kernel time variables</h3>

<img align="left" src="pic/pogo5.gif" alt="gif"><a href=
"http://www.eecis.udel.edu/~mills/pictures.htm">from <i>Pogo</i>,
Walt Kelly</a> 

<p>The turtle is been swimming in the kernel.<br clear="left">
</p>

<hr>
<h4>Synopsis</h4>

<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> 

<h4>Description</h4>

This program is useful only with special kernels described in the
<a href="kern.htm">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. 

<h4>Options</h4>

<dl>
<dt><tt>-c</tt></dt>

<dd>Display the execution time of <tt>ntptime</tt> itself.</dd>

<dt><tt>-e <i>est_error</i></tt></dt>

<dd>Specify estimated error, in microseconds.</dd>

<dt><tt>-f <i>frequency</i></tt></dt>

<dd>Specify frequency offset, in parts per million.</dd>

<dt><tt>-h</tt></dt>

<dd>Display help information.</dd>

<dt><tt>-m <i>max_error</i></tt></dt>

<dd>Specify max possible errors, in microseconds.</dd>

<dt><tt>-o <i>offset</i></tt></dt>

<dd>Specify clock offset, in microseconds.</dd>

<dt><tt>-r</tt></dt>

<dd>Display Unix and NTP times in raw format.</dd>

<dt><tt>-s <i>status</i></tt></dt>

<dd>Specify clock status. Better know what you are doing.</dd>

<dt><tt>-t <i>time_constant</i></tt></dt>

<dd>Specify time constant, an integer in the range 0-10.</dd>
</dl>

<hr>
<a href="index.htm"><img align="left" src="pic/home.gif" alt=
"gif"></a>
<address><a href="mailto:mills@udel.edu">David L. Mills
&lt;mills@udel.edu&gt;</a></address>
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