PHP Can't download over 40MB weight files - php

Question

I created a simple file to download files.
I have the following code:
function DownloadFile($file) { // $file = include path
if(file_exists($file)) {
header('HTTP/1.0 200 OK', true, 200);
header('Content-Description: File Transfer');
header('Content-Type: application/zip');
header('Content-Disposition: attachment; filename='.basename($file));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
ob_clean();
flush();
readfile($file);
exit;
}
}
The problem is if I try to download files over 40-50MB the file is downloaded blank(0KB) but if I try below 40MB it is working perfectly.
What is the problem?

Answer 1

Like explained in this article https://www.sitepoint.com/community/t/php-file-size-download-limit/6541 you need to set
memory_limit = 128M
post_max_size = 300M
in php.ini file

Answer 2

The solution:
function DownloadFile($file) { // $file = include path
if(file_exists($file)) {
header('HTTP/1.0 200 OK', true, 200);
header('Content-Description: File Transfer');
header('Content-Type: application/zip');
header('Content-Disposition: attachment; filename='.basename($file));
header('Content-Transfer-Encoding: chunked');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: ' . filesize($file));
ob_clean();
flush();
ob_end_flush();
if ($fd = fopen ($file, "r")) {
set_time_limit(0);
ini_set('memory_limit', '1024M');
while(!feof($fd)) {
echo fread($fd, 4096);
flush();
}
}
}
}