#!/usr/bin/perl -w
BEGIN # run before anything
{
  my $POST_MAX = -1;
  my $CL = defined($ENV{'CONTENT_LENGTH'}) ? $ENV{'CONTENT_LENGTH'} : 0;

    if(($POST_MAX > 0) and ($CL > $POST_MAX))
    {
        print "Content-Type: text/plain\n",
              "Status: 413\n\n",
              "413 Request entity too large";
        exit;
    }
}