Content-length and other HTTP headers?

Question

Does it give me any advantage if I set this header when generating normal HTML pages?

I see that some frameworks out there will set this header property and I was wo

Answer 1

The best way (that is working for me) of getting size of a remote file:

$head = array_change_key_case(get_headers($file, TRUE));
$filesize = $head['content-length'];