Listing 1: Time synchronizing script

#!/usr/bin/perl
use Socket;
use English;
     
$remote  = 'time.nist.gov';
$port    = 37; 
if ($port =~ /\D/) { $port = getservbyname($port, 'tcp') } 
die "No port" unless $port;
$iaddr   = inet_aton($remote)               || die "no host: $remote"; 
$paddr   = sockaddr_in($port, $iaddr);
$proto   = getprotobyname('tcp');
socket(SOCK, PF_INET, SOCK_STREAM, $proto)  || die "socket: $!"; 
connect(SOCK, $paddr)    || die "connect: $!";
     
$line = <SOCK>;
     
# Port 37 Returns Number of seconds since 1900 
# 25567 number of days since 1900 to 1970 
$time =  unpack("N",$line)-25567*60*60*24;
     
     
($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst)=localtime($time);
     
if($year > 99) 
{ 
        $year-=100;
}
$mon+=1;
     
$correction=time-$time;
     
$touch_format=sprintf("%02.2s%02.2s%02.2s%02.2s%02.2s.%02.2s",$year,$mon,$mday,$
hour,$min,$sec);
     
if($OSNAME eq "MSWin32") {
        system("date $mon-$mday-$year");
        system("time $hour:$min:$sec");
} else {
        system("date $touch_format");
}
     
print "Changed by $correction seconds\n"; 
close (SOCK)            || die "close: $!"; 
exit;