#!/usr/bin/perl -w
# Perl Raw 'time' TCP client
# http://www.perl.com/doc/manual/html/pod/perlipc.html

use strict;
use Socket;

my $SECS_of_70_YEARS = 2208988800;
sub ctime { scalar localtime(shift) }

my $iaddr = gethostbyname('localhost');
my $proto = getprotobyname('tcp');
my $port = getservbyname('time', 'tcp');
my $paddr = sockaddr_in(0, $iaddr);
my($host);

$| = 1;
printf "%-24s %8s %s\n",  "localhost", 0, ctime(time());

foreach $host (@ARGV) {
    printf "%-24s ", $host;
    my $hisiaddr = inet_aton($host)     || die "unknown host";
    my $hispaddr = sockaddr_in($port, $hisiaddr);
    socket(SOCKET, PF_INET, SOCK_STREAM, $proto)   || die "socket: $!";
    connect(SOCKET, $hispaddr)          || die "bind: $!";
    my $rtime = '    ';
    read(SOCKET, $rtime, 4);
    close(SOCKET);
    my $histime = unpack("N", $rtime) - $SECS_of_70_YEARS ;
    printf "%8d %s\n", $histime - time, ctime($histime);
}