Ubuntu Manpage: ntp_time - Tcl Time Service Client

NAME

       ntp_time - Tcl Time Service Client

SYNOPSIS

       package require Tcl  8.0

       package require time  ?1.2.1?

       ::time::gettime ?options? timeserver ?port?

       ::time::getsntp ?options? timeserver ?port?

       ::time::configure ?options?

       ::time::cget name

       ::time::unixtime token

       ::time::status token

       ::time::error token

       ::time::reset token ?reason?

       ::time::wait token

       ::time::cleanup token

_________________________________________________________________________________________________

DESCRIPTION

       This  package  implements  a  client  for  the  RFC  868  TIME  protocol  (http://www.rfc-
       editor.org/rfc/rfc868.txt) and also a minimal client for the RFC 2030 Simple Network  Time
       Protocol (http://www.rfc-editor.org/rfc/rfc2030.txt).  RFC 868 returns the time in seconds
       since 1 January 1900 to either tcp or udp clients. RFC 2030 also gives this time but  also
       provides a fractional part which is not used in this client.

COMMANDS

::time::gettime ?options? timeserver ?port?
Get the time from timeserver. You may specify any of the options listed for the
configure command here. This command returns a token which must then be used with
the remaining commands in this package. Once you have finished, you should use
cleanup to release all resources. The default port is 37.

::time::getsntp ?options? timeserver ?port?
Get the time from an SNTP server. This accepts exactly the same arguments as
::time::gettime except that the default port is 123. The result is a token as per
::time::gettime and should be handled in the same way.

Note that it is unlikely that any SNTP server will reply using tcp so you will
require the tcludp or the ceptcl package. If a suitable package can be loaded then
the udp protocol will be used by default.

::time::configure ?options?
Called with no arguments this command returns all the current configuration options
and values. Otherwise it should be called with pairs of option name and value.

-protocol number
Set the default network protocol. This defaults to udp if the tcludp package
is available. Otherwise it will use tcp.

-port number
Set the default port to use. RFC 868 uses port 37, RFC 2030 uses port 123.

-timeout number
Set the default timeout value in milliseconds. The default is 10 seconds.

-command number
Set a command procedure to be run when a reply is received. The procedure is
called with the time token appended to the argument list.

-loglevel number
Set the logging level. The default is 'warning'.

::time::cget name
Get the current value for the named configuration option.

::time::unixtime token
Format the returned time for the unix epoch. RFC 868 time defines time 0 as 1 Jan
1900, while unix time defines time 0 as 1 Jan 1970. This command converts the reply
to unix time.

::time::status token
Returns the status flag. For a successfully completed query this will be ok. May be
error or timeout or eof. See also ::time::error

::time::error token
Returns the error message provided for requests whose status is error. If there is
no error message then an empty string is returned.

::time::reset token ?reason?
Reset or cancel the query optionally specfying the reason to record for the error
command.

::time::wait token
Wait for a query to complete and return the status upon completion.

::time::cleanup token
Remove all state variables associated with the request.

% set tok [::time::gettime ntp2a.mcc.ac.uk]
% set t [::time::unixtime $tok]
% ::time::cleanup $tok

% set tok [::time::getsntp pool.ntp.org]
% set t [::time::unixtime $tok]
% ::time::cleanup $tok

proc on_time {token} {
if {[time::status $token] eq "ok"} {
puts [clock format [time::unixtime $token]]
} else {
puts [time::error $token]
}
time::cleanup $token
}
time::getsntp -command on_time pool.ntp.org

AUTHORS

       Pat Thoyts

BUGS, IDEAS, FEEDBACK

       This document, and the package it describes,  will  undoubtedly  contain  bugs  and  other
       problems.    Please   report   such   in   the   category   ntp  of  the  Tcllib  Trackers
       [http://core.tcl.tk/tcllib/reportlist].  Please also report any ideas for enhancements you
       may have for either package and/or documentation.

       When proposing code changes, please provide unified diffs, i.e the output of diff -u.

       Note further that attachments are strongly preferred over inlined patches. Attachments can
       be made by going to the Edit form of the ticket immediately after its creation,  and  then
       using the left-most button in the secondary navigation bar.

KEYWORDS

       NTP, SNTP, rfc 2030, rfc 868, time

COPYRIGHT

       Copyright (c) 2002, Pat Thoyts <patthoyts@users.sourceforge.net>