my @referers = ('$ips');
...
if ($#ARGV < 0)
  {
    $ENV{'REQUEST_METHOD'} =~ tr/[a-z]/[A-Z]/;
    if ($ENV{'REQUEST_METHOD'} eq 'POST') 
      {
        if(&check_url)
          {
            #get data from the web via Cgi.pm
          }
      }
    else { #if it didnt come with data then it needs a form to get it
      &form;
    }
  }
....
sub check_url
  {
      if ($ENV{'HTTP_REFERER'})
        {
          my $referer;
          foreach $referer (@referers)
            {
              if ($ENV{'HTTP_REFERER'} =~ m|https?://([^/]*)$referer|i)
                {
                  return 0; 
                }
              else                       #the else
                {                        #spoken of
                  return 1;              # above
                }                        #consists of these 4 lines
            }
        } 
      html_start("ERROR!");            #the two lines i want to run
      report_error("ERROR","Source check failed");          #if invalid referer
    }