# Net::Time.pm
#
-# Copyright (c) 1995 Graham Barr <Graham.Barr@tiuk.ti.com>. All rights
-# reserved. This program is free software; you can redistribute it and/or
+# Copyright (c) 1995-1998 Graham Barr <gbarr@pobox.com>. All rights reserved.
+# This program is free software; you can redistribute it and/or
# modify it under the same terms as Perl itself.
package Net::Time;
-=head1 NAME
-
-Net::Time - time and daytime network client interface
-
-=head1 SYNOPSIS
-
- use Net::Time qw(inet_time inet_daytime);
-
- print inet_time('localhost');
- print inet_time('localhost', 'tcp');
-
- print inet_daytime('localhost');
- print inet_daytime('localhost', 'tcp');
-
-=head1 DESCRIPTION
-
-C<Net::Time> provides subroutines that obtain the time on a remote machine.
-
-=over 4
-
-=item inet_time ( HOST [, PROTOCOL])
-
-Obtain the time on C<HOST> using the protocol as defined in RFC868. The
-optional argument C<PROTOCOL> should define the protocol to use, either
-C<tcp> or C<udp>. The result will be a unix-like time value or I<undef>
-upon failure.
-
-=item inet_daytime ( HOST [, PROTOCOL])
-
-Obtain the time on C<HOST> using the protocol as defined in RFC867. The
-optional argument C<PROTOCOL> should define the protocol to use, either
-C<tcp> or C<udp>. The result will be an ASCII string or I<undef>
-upon failure.
-
-=back
-
-=head1 AUTHOR
-
-Graham Barr <Graham.Barr@tiuk.ti.com>
-
-=head1 REVISION
-
-$Revision: 2.0 $
-
-=head1 COPYRIGHT
-
-Copyright (c) 1995 Graham Barr. All rights reserved. This program is free
-software; you can redistribute it and/or modify it under the same terms
-as Perl itself.
-
-=cut
-
use strict;
-use vars qw($VERSION @ISA @EXPORT_OK);
+use vars qw($VERSION @ISA @EXPORT_OK $TIMEOUT);
use Carp;
use IO::Socket;
require Exporter;
+use Net::Config;
+use IO::Select;
@ISA = qw(Exporter);
@EXPORT_OK = qw(inet_time inet_daytime);
-$VERSION = sprintf("%d.%02d", q$Revision: 2.0 $ =~ /(\d+)\.(\d+)/);
+$VERSION = "2.09"; # $Id: //depot/libnet/Net/Time.pm#9 $
+
+$TIMEOUT = 120;
sub _socket
{
- my($pname,$pnum,$host,$proto) = @_;
+ my($pname,$pnum,$host,$proto,$timeout) = @_;
$proto ||= 'udp';
my $port = (getservbyname($pname, $proto))[2] || $pnum;
- my $me = IO::Socket::INET->new(PeerAddr => $host,
- PeerPort => $port,
- Proto => $proto
- );
+ my $hosts = defined $host ? [ $host ] : $NetConfig{$pname . '_hosts'};
+
+ my $me;
+
+ foreach $host (@$hosts)
+ {
+ $me = IO::Socket::INET->new(PeerAddr => $host,
+ PeerPort => $port,
+ Proto => $proto
+ ) and last;
+ }
+
+ return unless $me;
$me->send("\n")
- if(defined $me && $proto eq 'udp');
+ if $proto eq 'udp';
- $me;
+ $timeout = $TIMEOUT
+ unless defined $timeout;
+
+ IO::Select->new($me)->can_read($timeout)
+ ? $me
+ : undef;
}
sub inet_time
{
my $s = _socket('time',37,@_) || return undef;
my $buf = '';
+ my $offset = 0 | 0;
- # the time protocol return time in seconds since 1900, convert
- # it to a unix time (seconds since 1970)
+ return undef
+ unless $s->recv($buf, length(pack("N",0)));
- $s->recv($buf, length(pack("N",0))) ? (unpack("N",$buf))[0] - 2208988800
- : undef;
+ # unpack, we | 0 to ensure we have an unsigned
+ my $time = (unpack("N",$buf))[0] | 0;
+
+ # the time protocol return time in seconds since 1900, convert
+ # it to a the required format
+
+ if($^O eq "MacOS") {
+ # MacOS return seconds since 1904, 1900 was not a leap year.
+ $offset = (4 * 31536000) | 0;
+ }
+ else {
+ # otherwise return seconds since 1972, there were 17 leap years between
+ # 1900 and 1972
+ $offset = (70 * 31536000 + 17 * 86400) | 0;
+ }
+
+ $time - $offset;
}
sub inet_daytime
}
1;
+
+__END__
+
+=head1 NAME
+
+Net::Time - time and daytime network client interface
+
+=head1 SYNOPSIS
+
+ use Net::Time qw(inet_time inet_daytime);
+
+ print inet_time(); # use default host from Net::Config
+ print inet_time('localhost');
+ print inet_time('localhost', 'tcp');
+
+ print inet_daytime(); # use default host from Net::Config
+ print inet_daytime('localhost');
+ print inet_daytime('localhost', 'tcp');
+
+=head1 DESCRIPTION
+
+C<Net::Time> provides subroutines that obtain the time on a remote machine.
+
+=over 4
+
+=item inet_time ( [HOST [, PROTOCOL [, TIMEOUT]]])
+
+Obtain the time on C<HOST>, or some default host if C<HOST> is not given
+or not defined, using the protocol as defined in RFC868. The optional
+argument C<PROTOCOL> should define the protocol to use, either C<tcp> or
+C<udp>. The result will be a time value in the same units as returned
+by time() or I<undef> upon failure.
+
+=item inet_daytime ( [HOST [, PROTOCOL [, TIMEOUT]]])
+
+Obtain the time on C<HOST>, or some default host if C<HOST> is not given
+or not defined, using the protocol as defined in RFC867. The optional
+argument C<PROTOCOL> should define the protocol to use, either C<tcp> or
+C<udp>. The result will be an ASCII string or I<undef> upon failure.
+
+=back
+
+=head1 AUTHOR
+
+Graham Barr <gbarr@pobox.com>
+
+=head1 COPYRIGHT
+
+Copyright (c) 1995-1998 Graham Barr. All rights reserved.
+This program is free software; you can redistribute it and/or modify
+it under the same terms as Perl itself.
+
+=for html <hr>
+
+I<$Id: //depot/libnet/Net/Time.pm#9 $>
+
+=cut