This is my first attempt at writing an actual CGI script, and I would like any comments or suggestions as to how to make this script more secure, since I would like to put this on my website, which is on jcwren's server.
This script is supposed to keep track of the number of downloads of two different files. If you click the link, it should update a text file, then redirect to the actual file to be downloaded.
#!/usr/bin/perl -Tw
use strict;
use CGI qw(:all);

my $CGI = new CGI;
my $file;
my $countfile="downloadcounts.txt";
my $OS_Type=$CGI->param("OS");
my %OS_Count=();
my $OS_Name;
my $count;

open(COUNT,"$countfile")||die"Can't open: $!\n";
while(<COUNT>){
  ($OS_Name,$count)=split /=/;
  chomp($OS_Name);
  chomp($count);
  $OS_Count{$OS_Name}=$count;
}
close COUNT;

if($OS_Type=~/Linux/ || $OS_Type=~/Windows/){
  if(exists $OS_Count{$OS_Type}){
    $OS_Count{$OS_Type}++;
  }
  &write(\%OS_Count);
  if($OS_Type=~/Windows/){
    $file="http://tstanley.perlmonk.org/QuizTaker32-V108.zip";
    $CGI->redirect($file);
  }elsif($OS_Type=~/Linux/){
    $file="http://tstanley.perlmonk.org/QuizTaker-V1.08.tar.gz";
    $CGI->redirect($file);
  }else{
    print $CGI->header();
    print $CGI->start_html('Try Again!');
    print $CGI->h1(-align=>'center','Incorrect OS!!');
    print $CGI->end_html();
  }
}elsif($OS_Type=~/Show/){
  print $CGI->header();
  print $CGI->start_html('Number of Downloads');
  
  foreach my $key(keys %OS_Count){
    print $CGI->h3("$key = $OS_Count{$key} downloads");
  }

  print $CGI->end_html();
}

sub write{
  my $Hash=shift;

  open(COUNT,">$countfile")||die"Can't open: $!\n";
  
  foreach my $key (keys %$Hash){
    print COUNT "$key=$$Hash{$key}\n";
  }

  close COUNT;
}

[download]

TStanley
--------
There's an infinite number of monkeys outside who want to talk to us
about this script for Hamlet they've worked out
-- Douglas Adams/Hitchhiker's Guide to the Galaxy

In reply to Advice on a CGI script by TStanley

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