about downloading

KFC

I have developed a website with PHP. I am going to offer something to download. I got a piece of code as follow

<?php 
  header("Content-type: application/octet-stream"); 
  header("Content-disposition: attachment; filename=aaa.rm"); 
  header("Content-length: " . filesize("aaa.rm")); 

  echo file_get_contents("aaa.rm"); 
?>

The code above seems very simple but I am worrying about the efficiency. Suppose the file I offered to download is very large (>200M), will it be long for reading the content of the file in before the actual download process goes on? If so, any better solution for this case (rather than offer an real url)?

Thanks in advance!

thorpe

as for how long filesize() would take to determine a 200M file, your talking milliseconds.

i belive this is your best option.

mtmosier

file_get_contents is going to pull that entire file into memory. A 200mb file is likely going to cause problems on that front. You could try readfile, but my understanding is that it also has issues with large files. You might want to go back to fopen.

KFC

I have a test. When I try to download a file of 19M, only 183bytes are actually download!!! Here is my code again

<?php
$absfile = "aaa.rm";
$len = filesize($absfile);
$fd = fopen($absfile, "rb");
$contents = fread($fd, $len);
fclose($fd);

header("Content-type: application/octet-stream");
header("Content-disposition: attachment; filename=$absfile");
header("Content-length: " .$len);

echo $content;

KFC

I try to use readfile instead, the code is listed as follow

<?php 
  $absfile = "aaa.rm"; 
  //$len = filesize($absfile); 

  header("Content-type: application/octet-stream"); 
  header("Content-disposition: attachment; filename=$absfile"); 
  //header("Content-length: " .$len); 

  readfile($absfile); 
?>

If the filesize is remarked, everything is all right. however, this makes flashget fail to download the file. but if the size of aaa.rm is larger than 8M, filesize fails (the problem of buffersize).

phrygianmodal

I'm running pretty much the code in the above post, but for some reason the maximum file transfer size is 1.9MB. I've checked all the usual memory settings and it doesn't look like a PHP issue (that is, I've got it allocated the 8MB it wants; not that this effects anything, but it's just one more thing I'm sure is not wrong with it). Any hints on what might fix this?

(dl_file include directory information, file_name does not; for what it matters, consider them the same)

header( "Pragma: public" );
header( "Expires: 0" );
header( "Cache-Control: must-revalidate, post-check=0, pre-check=0" );
header( "Cache-Control: public" );
header( "Content-Description: File Transfer" );
header( "Content-Type: audio/mpeg" );
//header( "Content-Length: " . filesize( $dl_file ) );
header( "Content-Disposition: attachment; filename=\"$file_name\";" );
header( "Content-Transfer-Encoding: binary" );
@readfile( $dl_file );

No, it doesn't work even if Content-Length is uncommented. If I print out filesize( $dl_file ) on the page, it registers correctly, thus making this ever more the mystery.

Thanks.

mtmosier

@
I've never heard of this problem, aside from files over 2gb. I just tried it on my computer and I correctly got the size of a 340mb file. In what way does it fail? Wrong result? An error? And what OS and version of PHP are you using?

@
This sounds very much like a problem mentioned in the user notes in the manual. That might be the place to start looking.

regarding php5:
i found out that there is already a disscussion @php-dev about readfile() and fpassthru() where only exactly 2 MB will be delivered.