[thelist] Header Problems with file downloads

[The Lists]

Hi,

I have a button on a form whereby if the use presses it it will (or 
should) download the contents of a MYSQL table into a csv file
I seem to be having porblems with the headers...I have the following:

file_put_contents_php4("data.csv", $output);
# creates csv file and outputs it to data.csv

header("Content-type: application/csv;");
header("Content-disposition: attachment; filename=data.csv");

But when I open the csv file it is just the current web page and NOT the 
csv file in question...I presume it is the headers which are wrong..any 
suggestions please?

TIA
Alexis