Why does download script never save the last chunk?

[empiresolutions]

I'm using the following script to download large file (>100Mb). It works well except that it seems to not ever save the final chunk. If the file is 149,499 on the server, it finishes its download at 145,996. Why? How do I get the last 2% or so to flush and complete the download? Thank much for your help.

FYI, this also happens the same on smaller files so its not stopping for time or file size issues.

 
$path = "the/file/path.mp4";

$headsize = get_headers($path,1);

$ext = str_from_last_occurrence($_vars['filepath'],".");

if ($ext=="mp3") { $type = "audio"; }
elseif ($ext=="mp4") { $type = "video"; }

function readfile_chunked($filename,$retbytes=true) {

	// Stream file
	$handle = fopen($filename, 'rb');
	$chunksize = 1*(1024*1024); // how many bytes per chunk
	$buffer = '';
	$cnt =0;

   if ($handle === false) {
       return false;
   }

   while (!feof($handle)) {
       $buffer = fread($handle, $chunksize);
       echo $buffer;
       ob_flush();
       flush();
       if ($retbytes) {
           $cnt += strlen($buffer);
       }
   }

   $status = fclose($handle);

   if ($retbytes && $status) {
       return $cnt; // return num. bytes delivered like readfile() does.
   }

   return $status;

}

header('Cache-Control: no-cache, no-store, max-age=0, must-revalidate');
header("Content-type: ".$type."/".$ext);
header('Content-Length: ' . (string)($headsize['Content-Length']));
header('Content-Disposition: attachment; filename="'.str_from_last_occurrence($_vars['filepath'],"/").'"');
header("Content-Transfer-Encoding: binary");

readfile_chunked($path);

exit;

[HaLo2FrEeEk]

I'm using this exact same function and it works fine for me. I can download huge files just fine. Are the file you're downloading located on your own server? If so then don't bother getting the headers, that's just wasteful, use filesize() instead. Here's the download headers I'm setting, unmodified from my site's code, so they won't be plug n' play for you:

header("Cache-Control: ");
header("Pragma: ");
header("Content-type: application/octet-stream");
header("Content-Disposition: attachment; filename=\"".$download."\"");
header("Content-length:".(string)(filesize($path.$download)));
readfile_chunked($path.$download);

[empiresolutions]

the files are hosted on a CDN.

[code green]

You are not checking fread for error, so if the last chunk fails,
you will not see it.

[empiresolutions]

can you give me an example of how to read the error?

[code green]

fread returns a string or FALSE on error.
This doesn't tell you the problem of course.
But with error_reporting enabled you may be given a clue

[empiresolutions]

$buffer = fread($handle, $chunksize);
echo $buffer;

Does this not count as checking for an error? It returns nothing important that I see.

[code green]

This does not handle anything when FALSE is returned.
Is error_reporting enabled in php.ini?

[empiresolutions]

error_reporting = E_ERROR;

[code green]

This settings shows only the basic errors.
When debugging use

error_reporting(E_ALL | E_STRICT);

At the beginning of scripts.
File errors will then be output