use autodie;

my $datei = 'my_huge_video.mp4';
my $type = 'whatever';
my $groesse = (stat $datei)[7];
my $name = 'Twelve Dances With God: In the Pay of Spain';

my $header = <<"EOH";
Content-Type: $type\nContent-length: $groesse
Content-Disposition: attachment; filename: "$name";

EOH

{
    local $| = 1;
    print $header;
    open my $input,'<',$datei;
    my $buffer;
    while (sysread $input,$buffer,1024*1024) {
	syswrite STDOUT,$buffer;
    }
}