PHP - Attaching Text File - Mail Not Working - php

Question

I am writing an application that is to send an email that contains a CSV as an attachment. However, it is not working. The mail function does not return false (implying that it succeeded); however, the email is not being sent.
I have sent/received email from the server before, so I do not believe that is the issue. However, I do not really have any experience with sending attachments through PHP, so I would suspect the issue lies in there. I have followed this tutorial to an extent: http://www.texelate.co.uk/blog/post/56-send-an-email-attachment-with-php/
Here are some code snippets:
$file = tmpfile();
// code omitted
$fileArray = array(); // this gets filled with more arrays/lines of data
// code omitted
try {
foreach($fileArray as $line) {
var_dump($line);
fputcsv($file, $line);
}
// begin mailing
$toEmail = 'myemail';
$subject = "Insurance Registration";
fseek($file, 0);
$attachData = fread($file, 1024);
$fileName = $lastName . "_" . date('Y');
$random = md5(time());
$boundary = "==Multipart_Boundary_x{$random}x";
$headers = "From: Test \nMIME-Version: 1.0\n" . "Content-Type: multipart/mixed\n" . "boundary=\"{$boundary}\"";
$message = "Testing!.\n\n " . "-{$boundary}\n " . "Content-Type= text/plain; charset=\"iso-8859-1\n" . "Content-Transfer-Encoding 7bit\n\n " . "Testing Again " . "\n\n ";
$attachData = chunk_split(base64_encode($attachData));
$message .= "--{$boundary}\n" . "Content-Type: text/plain;\n" . "name=\"{$fileName}\"\n" . "Content-Disposition: attachment;\n" . " filename=\"{$fileName}\"\n" . " . Content-Transfer-Encoding: base64\n\n" . $attachData . "\n\n" . "-{$boundary}-\n";
} catch (Exception $e) {
echo $e->getMessage();
}
if(mail($toEmail, $subject, $message, $headers)) {
} else {
$hasError = true;
}
if($hasError) {
echo "<h2>Error Submitting form. Please check your input and try again</h2>";
} else {
header('Location: success.php');
}
I get redirected to the success page, but never receive an email. Thanks!