If you're hoping for a nice progress bar, unfortunately, that is, as far as I know, not possible without some considerable Javascript wizardry. You might have some luck with just printing to STDOUT in an unbuffered way (although you'll need to make sure that your webserver isn't waiting to parse the entire document before serving). The most you'll achieve with that method though is something like a text-based progress bar. Unfortunately, there's no good way to do what you want (that I know of, anyhow). If you do find a good solution, be sure to let us all know of it.