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

use LWP::Simple;

# Provide the URL for file to monitor
my $url = "ftp://ftp.ncbi.nlm.nih.gov/blast/db/FASTA/pdbnt.gz";
my $file = "pdbnt.gz";

# Invoke the LWP mirror utility which will compare
# the files by date stamp
my $rc = mirror($url, $file);

# If downloaded OK then 200 code
# If file is same date as local copy it returns
# 304 code For details on various codes, see
# ftp://ftp.rfc-editor.org/in-notes/rfc2616.txt
if ($rc == 200) {
   # Could send email to inform user !
    print "$file downloaded correctly\n";
    }
elsif ($rc == 304) {
    print "$file is up to date\n"
    }
elsif (!is_success($rc)) {
    print "Problem code:$rc ", status_message($rc), "($url)\n";
}