PHP offered download interrupted after X number of KB everytime

I have written a code that offers visitors to download a csv file which is of 1.1M in size. If one visits this script, download is interrupted around 30-40K (as shown below in wget output) while if he downloads it via a direct link like http://domain.com/events.csv it works just fine. I believe this has something to do with php configuration values on the server but i have played almost with all values[relevant and non-relevant] such as

• post_max_size [upto 90M]
• max_file_upload [upto 90M]
• max_execution_time [0 and upto 600]
• max_input_time [0 and upto 600]
• memory_limit [upto 1024M]

Following contains my code:

 <?php

$realpath="/home/user/public_html/events.csv";
$size = intval(sprintf("%u", filesize($realpath)));

@ini_set('zlib.output_compression', 0);
header("Content-Type: application/force-download");
header("Content-Type: application/octet-stream");
header("Content-Type: application/download");;
header("Content-Disposition: attachment;filename=events.xls"); 
header("Content-Transfer-Encoding: binary ");
header("Pragma: public");
header('Cache-Control: no-store, no-cache, must-revalidate'); 
header('Cache-Control: pre-check=0, post-check=0, max-age=0');
header ("Pragma: no-cache");
header("Expires: 0");
head开发者_如何学Cer("Content-Description: File Transfer");
header("Content-Type: text/csv");
header("Content-Length: ". $size);

// also tried with having a flush(); here
// also tried with file_get_contents();
//also tried with wrapping the file_get_contents() or readfile() call inside ob_start() and ob_flush()+ob_clean()
readfile($realpath);
exit;

?>

Here is the wget output

wget "http://domain.com/test.php"
--2011-06-26 19:47:55--  http://domain.com/test.php
Resolving domain.com... 69.117.110.115
Connecting to domain.com|69.117.110.115|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1139844 (1.1M) [text/csv]
Saving to: `test.php'

 3% [===>                                                                                                                            ] 36,373      --.-K/s   in 11s     

2011-06-26 19:48:11 (3.29 KB/s) - Connection closed at byte 36373. Retrying.

--2011-06-26 19:48:12--  (try: 2)  http://domain.com/test.php
Connecting to domain.com|69.117.110.115|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1139844 (1.1M) [text/csv]
Saving to: `test.php'

 3% [===>                                                                                                                            ] 40,469      --.-K/s   in 11s     

2011-06-26 19:48:24 (3.66 KB/s) - Connection closed at byte 40469. Retrying.

If i remove the header() required to offer a download and just echo the contents, then Chrome shows that the test.php was around 1.09M plus some more request, adds upto 1.1M[even in this case wget of test.php shows same behaviour as above], while firefox firebug shows that request was between 140K-300K[still not displaying all contents.

Check http://www.php.net/manual/en/function.readfile.php and search for: large. Copy-paste the code :)