#! /usr/local/bin/perl -w

use strict;
use Net::FTP;

my $host = 'ftp.example.com';
my $user = 'anonymous';
my $pass = 'grinder@localhost';
my $remote = '/pub';

my $ftp = Net::FTP->new($host);   # error
$ftp->login($user,$pass);         # checking
my @listing = $ftp->dir($remote); # omitted

my $latest_timestamp = 0;
my $latest = undef;
my $cur_year = (localtime)[5] + 1900;

for my $line( @listing ) {
  my( $prot, $links, $user, $group, $size, $month, $day, $yeartime, $entry ) =
  ($line =~ /^(\S+)\s+(\d+)\s+(\w+)\s+(\w+)\s+(\d+)\s+(\w+)\s+(\S+)\s+(.*)$/);

  if( $entry =~ /^(\d\d)(\d\d)i86\.exe$/ ) {
    my( $year, $hour, $min ) = do {
      $yeartime =~ /^(\d\d):(\d\d)$/
        ? ( $cur_year, $1, $2 )
        : ( $yeartime,  0,  0 )
    };
    my $timestamp = sprintf '%04d%02d%02d%02d%02d',
      $year, $month, $day, $hour, $min;
    if( $latest_timestamp lt $timestamp ) {
      $latest_timestamp = $timestamp;
      $latest = $entry;
    }
  }
}

exit unless $latest_timestamp;

my $prev = undef;
if( open IN, 'latest' ) {
  $prev = <IN>;
  close IN;
  chomp $prev;
}

if( !defined($prev) or $prev lt $latest_timestamp ) {
  $ftp->get("$remote/$entry");
  open OUT '>latest' or die "latest for output: $!\n";
  print "$latest_timestamp\n";
  close OUT;
}