xref: /freebsd-10.3-release/contrib/ntp/scripts/calc_tickadj/calc_tickadj-opts.def

/* -*- Mode: Text -*- */
AutoGen Definitions perlopt;

#include autogen-version.def

prog-name	= calc_tickadj;
prog-title	= 'Calculates "optimal" value for tick given ntp drift file.';
package		= ntp;
#include	version.def

long-opts;
gnu-usage;

flag = {
    name        = drift-file;
    value       = d;
    arg-type    = string;
    arg-default = '/etc/ntp/drift';
    descrip     = 'Ntp drift file to use';
    doc         = 'Use the specified drift file for calculations';
};

flag = {
    name        = tick;
    value       = t;
    arg-type    = number;
    descrip     = 'Tick value of this host';
    doc         = 'The current tick which to adjustment will be calculated';
};

doc-section = {
    ds-type     = 'DESCRIPTION';
    ds-format   = 'texi';
    ds-text     = <<- _EndOfDoc
The @code{calc_tickadj} 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. 

The example output of 
@example
$ ./calc_tickadj
81.699 (drift)
9999 usec; 9999779 nsec
$ cat /etc/ntp/drift
-23.159
@end example

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.

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

@code{calc_tickadj} tries to determine the the tick value by using
@code{tickadj} program from ntp package. If this doesn't work you can specify
current tick manually on command line.
	_EndOfDoc;
};