writing a binary file to a browser

I am trying to open a binary file from a URL, and then send that file back to the user's browser (after setting the appropriate content-type). I think i have a handle on how to open the file : using either fread() or file() however, i am not sure how to iterate through the bytes, get the file size, and write the bytes back to the browser? can anyone point me in the correct direction? Even if it is just the function name, that is helpful as I can look up the info in the php manual. thanks in advance.... mike chambers mesh@speakeasy.org