PHP downloads at 0 bytes - php

Question

I have ZIP files in a directory that is one step up from the root directory (to prevent hotlinking etc...). Here is the code:
<?php
$filename = $_GET['id'];
if(!$filename){
header("Location: index.html");
} else {
function send_download($filename){
$file_path = '../../../../downloads/' . $filename . '.zip';
$file_size=#filesize($file_path);
header("Content-Type: application/x-zip-compressed");
header("Content-disposition: attachment; filename=$filename");
header("Content-Length: $file_size");
readfile($file_path);
exit;
}
send_download($filename);
}
?>
All the ZIP files are fine but using this method on an 'a' tag causes the downloads to be 0 bytes in file size! :(
Any ideas as to why?
Many thanks!

Answer 1

Can you try changing the Content-type to the following:
Content-type: application/x-zip;
And before you do, check if the file exists.
<?php
$filename = $_GET['id'];
if(!$filename){
header("Location: index.html");
} else{
function send_download($filename){
$file_path = '../../../../downloads/' . $filename . '.zip';
if (file_exists($file_path))
{
$file_size=#filesize($file_path);
header("Content-Type: application/x-zip-compressed");
header("Content-disposition: attachment; filename=$filename");
header("Content-Length: $file_size");
readfile($file_path);
exit;
}
send_download($filename);
}
else
die("Error 404!");
}
?>

Answer 2

header("Location: http://www.fqdn.tld/file.ext");
Based on _GET["id"] being > 0 and not null, you've created a function which has been used directly after, so you've just added more lines of code for no required purpose.
I see you have added an "#" sign as people have previously commented, however, the only way for you to begin fixing this is by:
Removing the # sign as you should never use it, very bad practice, you should cater for all exceptions in your code, it makes for a really good programmer. (Scripting in PHP)
error_reporting(E_ALL);
Place point b) on it's own line but after the <?php - so we can see a full list of errors.
Your code is fine, the problem you have is permissions, ensure that apache has access to your "files" repository, the fact you are able to check that the file is there suggest slight permissions and the files exists, the point that 0 bytes are being returned suggest reading privileges are denied at Apache level.

Answer 3

Right, after a bit of Googling and some blood, sweat and tears I have finally found a solution!
<?php
$filename = $_GET['id'];
header('Content-type: application/zip');
header("Content-Disposition: attachment; filename=" . $filename);
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
readfile('../../downloads/' . $filename . ".zip");
exit;
?>
Many thanks to all of whom shed some light on this!

Answer 4

And here is the code with the filesize:
<?php
$filename = $_GET['id'];
$file = "../../downloads/" . $filename . ".zip";
header('Content-type: application/zip');
header("Content-Disposition: attachment; filename=" . $file);
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Content-length: " . filesize($file));
readfile($file);
//echo filesize($file);
exit;
?>

Answer 5

Only one mistake we all are doing check below.
readfile($file); //$file should be relative not absolute. That's it.
Thanks,
Anirudh Sood.