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<h1 class="settitle">calc_tickadj User's Manual</h1>
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<h2 class="unnumbered">calc_tickadj User's Manual</h2>

<p>This document describes the use of the NTP Project's <code>calc_tickadj</code> program. 
This document applies to version 4.2.8p12 of <code>calc_tickadj</code>.

  <div class="shortcontents">
<h2>Short Contents</h2>
<ul>
<a href="#Top">calc_tickadj User's Manual</a>
</ul>
</div>

<ul class="menu">
<li><a accesskey="1" href="#calc_005ftickadj-Description">calc_tickadj Description</a>:        Description
<li><a accesskey="2" href="#calc_005ftickadj-Invocation">calc_tickadj Invocation</a>:         Invoking calc_tickadj
</ul>

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<p><hr>
<a name="calc_005ftickadj-Invocation"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#calc_005ftickadj-Description">calc_tickadj Description</a>,
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<h3 class="section">Invoking calc_tickadj</h3>

<p><a name="index-calc_005ftickadj-1"></a><a name="index-Calculates-_0022optimal_0022-value-for-tick-given-ntp-drift-file_002e-2"></a>
The <code>calc_tickadj</code> script uses provided ntp drift file to generate optimal
tick value. Generally, ntpd can do better job if the drift value is the
smallest possible number.

  <p>The example output of
<pre class="example">     $ ./calc_tickadj
     81.699 (drift)
     9999 usec; 9999779 nsec
     $ cat /etc/ntp/drift
     -23.159
</pre>
  <p>means the following. If tick on that box is 10,000, by making the value 9999
we'll shift the box from its current drift of -23.159 to a drift of 81.699, and
in doing so we'll speed the clock up a little every second instead of slowing
the clock down a little.

  <p>If 'tick' on that box is 10,000,000 then by setting it to 9999779 the drift
value will be somewhere around 0.0.

  <p><code>calc_tickadj</code> tries to determine the the tick value by using
<code>tickadj</code> program from ntp package. If this doesn't work you can specify
current tick manually on command line.

  <p>This section was generated by <strong>AutoGen</strong>,
using the <code>agtexi-cmd</code> template and the option descriptions for the <code>calc_tickadj</code> program.

<ul class="menu">
<li><a accesskey="1" href="#calc_005ftickadj-usage">calc_tickadj usage</a>:                   calc_tickadj help/usage (<span class="option">--help</span>)
<li><a accesskey="2" href="#calc_005ftickadj-drift_002dfile">calc_tickadj drift-file</a>:              drift-file option (-d)
<li><a accesskey="3" href="#calc_005ftickadj-tick">calc_tickadj tick</a>:                    tick option (-t)
<li><a accesskey="4" href="#calc_005ftickadj-exit-status">calc_tickadj exit status</a>:             exit status
</ul>

<div class="node">
<p><hr>
<a name="calc_005ftickadj-usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#calc_005ftickadj-drift_002dfile">calc_tickadj drift-file</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="#calc_005ftickadj-Invocation">calc_tickadj Invocation</a>
<br>
</div>

<h4 class="subsection">calc_tickadj help/usage (<span class="option">--help</span>)</h4>

<p><a name="index-calc_005ftickadj-help-3"></a>
This is the automatically generated usage text for calc_tickadj.

  <p>The text printed is the same whether selected with the <code>help</code> option
(<span class="option">--help</span>) or the <code>more-help</code> option (<span class="option">--more-help</span>).  <code>more-help</code> will print
the usage text by passing it through a pager program. 
<code>more-help</code> is disabled on platforms without a working
<code>fork(2)</code> function.  The <code>PAGER</code> environment variable is
used to select the program, defaulting to <span class="file">more</span>.  Both will exit
with a status code of 0.

<pre class="example">calc_tickadj - Calculates "optimal" value for tick given ntp drift file. - Ver. 4.2.7p467
USAGE: calc_tickadj [ -&lt;flag&gt; [&lt;val&gt;] | --&lt;name&gt;[{=| }&lt;val&gt;] ]...

    -d, --drift-file=str         Ntp drift file to use
    -t, --tick=num               Tick value of this host
    -?, --help                   Display usage information and exit
        --more-help              Pass the extended usage text through a pager

Options are specified by doubled hyphens and their name or by a single
hyphen and the flag character.
</pre>
  <div class="node">
<p><hr>
<a name="calc_005ftickadj-drift_002dfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#calc_005ftickadj-tick">calc_tickadj tick</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="#calc_005ftickadj-usage">calc_tickadj usage</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="#calc_005ftickadj-Invocation">calc_tickadj Invocation</a>
<br>
</div>

<h4 class="subsection">drift-file option (-d)</h4>

<p><a name="index-calc_005ftickadj_002ddrift_002dfile-4"></a>
This is the &ldquo;ntp drift file to use&rdquo; option. 
This option takes a string argument. 
Use the specified drift file for calculations
<div class="node">
<p><hr>
<a name="calc_005ftickadj-tick"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#calc_005ftickadj-exit-status">calc_tickadj exit status</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="#calc_005ftickadj-drift_002dfile">calc_tickadj drift-file</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="#calc_005ftickadj-Invocation">calc_tickadj Invocation</a>
<br>
</div>

<h4 class="subsection">tick option (-t)</h4>

<p><a name="index-calc_005ftickadj_002dtick-5"></a>
This is the &ldquo;tick value of this host&rdquo; option. 
This option takes a number argument. 
The current tick which to adjustment will be calculated
<div class="node">
<p><hr>
<a name="calc_005ftickadj-exit-status"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#calc_005ftickadj-tick">calc_tickadj tick</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="#calc_005ftickadj-Invocation">calc_tickadj Invocation</a>
<br>
</div>

<h4 class="subsection">calc_tickadj exit status</h4>

<p>One of the following exit values will be returned:
     <dl>
<dt><span class="samp">0 (EXIT_SUCCESS)</span><dd>Successful program execution. 
<br><dt><span class="samp">1 (EXIT_FAILURE)</span><dd>The operation failed or the command syntax was not valid. 
</dl>

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