11573Srgrimes\input texinfo    @c -*-texinfo-*-
21573Srgrimes@c %**start of header
31573Srgrimes@setfilename ntpdc.info
41573Srgrimes@settitle ntpdc: NTPD Control User's Manual
51573Srgrimes@include ../sntp/include/version.texi
61573Srgrimes@paragraphindent 2
71573Srgrimes@c %**end of header
81573Srgrimes
91573Srgrimes@ifinfo
101573SrgrimesThis file documents the use of the NTP Project's ntpdc, a program for
111573Srgrimescontrolling ntpd.
121573Srgrimes@end ifinfo
131573Srgrimes
141573Srgrimes@direntry
151573Srgrimes* ntpdc: (ntpdc).                               ntpd Control program
16148834Sstefanf@end direntry
171573Srgrimes
181573Srgrimes@titlepage
191573Srgrimes@title ntpdc: NTPD Control User's Manual
201573Srgrimes@subtitle ntpdc, version @value{VERSION}, @value{UPDATED}
211573Srgrimes@c @author Max @email{foo@ntp.org}
221573Srgrimes@end titlepage
231573Srgrimes
241573Srgrimes@c @page
251573Srgrimes@c @vskip 0pt plus 1filll
261573Srgrimes
271573Srgrimes@node Top, ntpdc Description, (dir), (dir)
281573Srgrimes@top ntpdc: NTPD Control User Manual
291573Srgrimes
301573SrgrimesThis document describes the use of the NTP Project's @code{ntpdc} program,
311573Srgrimesthat can be used to query a Network Time Protocol (NTP) server and
321573Srgrimesdisplay the time offset of the system clock relative to the server
33148834Sstefanfclock.  Run as root, it can correct the system clock to this offset as
3484260Sobrienwell.  It can be run as an interactive command or from a cron job.
351573Srgrimes
361573SrgrimesThis document applies to version @value{VERSION} of @code{ntpdc}.
371573Srgrimes
381573SrgrimesThe program implements the SNTP protocol as defined by RFC 5905, the NTPv4
391573SrgrimesIETF specification.
401573Srgrimes
4184260Sobrien@shortcontents
421573Srgrimes
431573Srgrimes@menu
4484260Sobrien* ntpdc Description::            Description
4584260Sobrien* ntpdc Invocation::		Invoking ntpdc
4684260Sobrien* Usage::                       Usage
471573Srgrimes@end menu
481573Srgrimes
491573Srgrimes@node ntpdc Description
501573Srgrimes@comment  node-name,  next,  previous,  up
5184260Sobrien@section Description
5284260Sobrien
5384260SobrienBy default, @code{ntpdc} writes the local data and time (i.e., not UTC) to the
5484260Sobrienstandard output in the format:
5584260Sobrien
5684260Sobrien@example
5784260Sobrien1996-10-15 20:17:25.123 (+0800) +4.567 +/- 0.089 secs
5884260Sobrien@end example
5984260Sobrien
6084260Sobrienwhere
611573SrgrimesYYYY-MM-DD HH:MM:SS.SUBSEC is the local date and time,
621573Srgrimes(+0800) is the local timezone adjustment (so we would add 8 hours and 0 minutes to convert the reported local time to UTC),
6384260Sobrienand
6484260Sobrienthe +4.567 +/- 0.089 secs indicates the time offset and
651573Srgrimeserror bound of the system clock relative to the server clock.
66148834Sstefanf
6784260Sobrien@include invoke-ntpdc.texi
6884260Sobrien
6984260Sobrien@node Usage
7084260Sobrien@comment  node-name,  next,  previous,  up
7184260Sobrien@section Usage
7284260Sobrien
7384260SobrienThe simplest use of this program is as an unprivileged command to
741573Srgrimescheck the current time, offset, and error in the local clock.
751573SrgrimesFor example:
76
77@example
78ntpdc ntpserver.somewhere
79@end example
80
81With suitable privilege, it can be run as a command or in a
82@code{cron} job to reset the local clock from a reliable server, like
83the @code{ntpdate} and @code{rdate} commands.
84For example:
85
86@example
87ntpdc -a ntpserver.somewhere
88@end example
89