Empty message when sending zip file with PHP - php

Question

**Update: Updated the code and added the email contents as seen in Gmail. **
I have a problem which I've been trying to solve a couple of days. But since I have been unable to make any progress, I'd like the help of someone else. I'm trying to send a zip file from my server to my email. However, the email is being sent empty. This is the code:
`$headers = "From: $from";
/* Generate boundary string */
$random = md5(time());
$headers .= "\r\nContent-Type: multipart/mixed; boundary=\"PHP-mixed-".$random."\"";
/* Read the file */
$attachment = chunk_split(base64_encode(file_get_contents("backup-$date-$time-9.zip")));
/* Define body */
$message = "--PHP-mixed-$random
Content-Type: text/plain; charset=\"iso-8859-1\"
Attached, please find your backup file.
--PHP-mixed-$random
Content-Type: application/zip; name=backup-$date-$time-9.zip
Content-Transfer-Encoding: base64
Content-Disposition: attachment
$attachment
--PHP-mixed-$random--"; // no intendation
$mail = mail($email, $subject, $message, $headers);
echo $mail ? "Email sent<br>" : "Email sending failed<br>";`
Thanks to all reading and wanting to help.
The resulting email as seen in Gmail is
Attached, please find your backup file.
--PHP-mixed-e44b531b0e0538185289abc521eda78d
Content-Type: application/zip; name=backup-29-11-2014-1417275285-9.zip
Content-Transfer-Encoding: base64
Content-Disposition: attachment
UEsDBBQAAAAIAFZ8fUUs...sUEsFBgAAAAACAAIAeAAAAD4B
AAAAAA==
--PHP-mixed-e44b531b0e0538185289abc521eda78d--

Answer 1

I got it working by doing the following changes:
Removed space character in From: headers, it's an invalid header otherwise
Changed boundary: to boundary=
Removed intendation in $message because that seems to break the email. The boundary string --PHP-mixed-random separates the different parts of the email, like plain text, html text, attachments from each other. When there are spaces in front of the boundary separator, it is not interpreted as the separator anymore, but as normal text.
Here's the code:
<?php
$from = "xxx#myserver";
$email = "xxx#gmail.com";
$subject = "backup file";
$date = "29-11-2014";
$time = "1417275285"; // test file "backup-29-11-2014-1417275285-9.zip" in the same folder
$headers = "From: $from"; // remove space
/* Generate boundary string */
$random = md5(time());
$headers .= "\r\nContent-Type: multipart/mixed; boundary=\"PHP-mixed-".$random."\""; // : to =
/* Read the file */
$attachment = chunk_split(base64_encode(file_get_contents("backup-$date-$time-9.zip")));
/* Define body */
$message = "--PHP-mixed-$random
Content-Type: text/plain; charset=\"iso-8859-1\"
Attached, please find your backup file.
--PHP-mixed-$random
Content-Type: application/zip; name=backup-$date-$time-9.zip
Content-Transfer-Encoding: base64
Content-Disposition: attachment
$attachment
--PHP-mixed-$random--"; // no intendation
$mail = mail($email, $subject, $message, $headers);
echo $mail ? "Email sent<br>" : "Email sending failed<br>";