How to download a temporary file

Question

I\'m trying to create a short PHP script that takes a JSON string, converts it to CSV format (using fputcsv), and makes that CSV available as a downloaded .csv file

Answer 1

One problem is that tmpfile() returns a file handle, while filesize takes a filename as parameter.
The following line:

header('Content-Length: ' . filesize($tmp));

probably gets evaluated as:

header('Content-Length: 0');

Check that all the calls to header() are executed before any output happens.