my $file = "$file_name";
if (-e $file) {
local *FH;
open FH, $file or die "Unable to open file";
if (-B $file){
binmode FH;
}
$r->content_type('application/octet-stream');
$r->set_content_length(-s FH);
$r->headers_out->add("Content-Disposition" => qq(attachment; filename="$display_filename"));
my $buffer;
$m->autoflush(1);
while (sysread(FH, $buffer, 262144)) {
$m->out($buffer);
}
$m->autoflush(0);
close FH;
return;