<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="content-type" content="text/html;charset=iso-8859-1"> <meta name="generator" content="HTML Tidy, see www.w3.org"> <title>ntptime - read and set kernel time variables</title> <link href="scripts/style.css" type="text/css" rel="stylesheet"> </head> <body> <h3><tt>ntptime</tt> - read and set kernel time variables</h3> <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> <p>The turtle has been swimming in the kernel.</p> <p>Last update: <!-- #BeginDate format:En2m -->11-Sep-2010 05:55<!-- #EndDate --> UTC</p> <br clear="left"> <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> <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> <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> <script type="text/javascript" language="javascript" src="scripts/footer.txt"></script> </body> </html>