title: Does md5_file download the file it is getting the checksum from?
body: <p>If I use md5_file to get the checksum of a remote file in PHP, does it download the file and them get the checksum or does it request the checksum from the remote server? Basically what I'm trying to figure out is if it is less bandwidth to do a MD5 check on a file to see if it has changed before I re-download the file, but if md5_file downloads the file to a temp location then does the check, I might as well just download the file straight-up anyway, right?</p>