asked on

Why is this zip file empty?

I've got a link that looks like this: http://loosecannonfitness.com/downloads.php?email=bruce@brucegust.com

It hits that page and, provided it gets appropriately validated, it hits this code:

$michelle_row=mysqli_fetch_assoc($michelle_query);
	$vivian="update hammons set download_success='Y' where email='$michelle_row[email]'";
	$vivian_query=mysqli_query($cxn, $vivian);
	if($michelle_row['workout']=="1775")
	{
		$filename="1775.zip";
	}
	else
	{
		$filename="Devildog.zip";
	}
	header("Content-Type: application/zip");
	header('Content-Disposition: attachment; filename='.$filename);

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The "update" part works great and I get the box that asks if I want to save or open the zip file. The problem is, although I can look at my server and see the "1775.zip" file that's over 22MB, when I go to download it, it's 0 bytes.

In other words, everything seems to be in place except for the content of the file.

What am I doing wrong?

SOLUTION

skullnobrains

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Bruce Gust

ASKER

First of all, I think your "skullnobrains" is both hilarious in that it's an obvious misnomer.

Secondly, there are two questions I have:

If the whole of my script looks like this:

<?php
include("carter.inc"); 
$cxn = mysqli_connect($host,$user,$password,$database)
or die ("couldn't connect to server");
$michelle="select * from hammons where email='$_GET[email]' and download_success<>'Y'";
$michelle_query=mysqli_query($cxn, $michelle);
if(!$michelle_query)
{
	$rats=mysqli_errnor($cxn).': '.mysqli_error($cxn);
	die($rats);
}
$michelle_count=mysqli_num_rows($michelle_query);
if(!$michelle_count>0)
{
	header("location:downloads_fail.php");
	exit();
}
else
{
	$michelle_row=mysqli_fetch_assoc($michelle_query);
	$vivian="update hammons set download_success='Y' where email='$michelle_row[email]'";
	$vivian_query=mysqli_query($cxn, $vivian);
	if($michelle_row['workout']=="1775")
	{
		$filename="1775.zip";
	}
	else
	{
		$filename="Devildog.zip";
	}
	header("Content-Type: application/zip");
	header('Content-Disposition: attachment; filename='.$filename);
}
?>

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Where does your suggestion belong?

Second question: I'm not familiar fpassthru. I went out to the manual (http://php.net/manual/en/function.fpassthru.php) and found this:

Reads to EOF on the given file pointer from the current position and writes the results to the output buffer.

Could you put that in layman's terms and explain to me what that means?

I appreciate you, friend! Glad you're up and running on a Saturday!

SOLUTION

Ray Paseur

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ASKER CERTIFIED SOLUTION

Insoftservice inso

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Bruce Gust

ASKER

Thank you!

skullnobrains

It sends the file line-by-line as if it were browser output, written with echo.

ray:

not quite. it acts the same as readfile (which is simpler btw, thanks @insoft for making it one line shorter) or stream copy to stream would act.

they copy the file block by block. the file is moved as fast as the disk and network can handle. the read side is mmapped and the write side is sent to the php output buffer which itself if flushed asynchronously to the webserver's / the system's buffers. in real life, on what i assume to be a lamp server, the file is mmapped by increments of 2 4k blocks at a time and flushed to apache's buffer ( which is large enough to handle the whole file in this case ). this is world's appart more efficient that reading line by line when it comes to zip files.