Is there some limit on a size of a file when causing a download with PHP?

Question

Trying to force-download file with PHP using usual:

header("Content-type: $type" );
header("Content-Disposition: attachment; filename=$name");
header('Content-Length: ' . filesize($path));

And it does successfully for files somewhere below 32 mb. For bigger ones it just returns zeroed file.

Obviously there's some kind of limit, but what sets it? Using Apache 2.2.11 and PHP 5.3.0.

Answer 1

Inside the php.ini you will see the setting.

I can't remember the option name off the top of my head, but I will look inside my php.ini now and try and find it.

Just remove it and it will work.

Added

Okay, someone please correct me if I am wrong, but is it

memory_limit

Answer 2

It seems like you're loading the entire file into RAM before sending it down to the recipient. You'll want to look into PHP Streams to be able to send the full file contents without having to read it all into RAM first: http://php.net/streams

Answer 3

I eventually stumbled on this post: http://w-shadow.com/blog/2007/08/12/how-to-force-file-download-with-php/. Adding all the headers recommended there and also using:

 ob_end_clean(); //turn off output buffering to decrease cpu usage

before any output - has helped. No more limitations observable. Files download completely even huge ones.

Answer 4

also may need to set_time_limit(0);