Sending file with email attachment it's like send file via HTTP protocol. You need to serialize file contents by base64_encode(), and put headers what indicate attached file type:
<?php
$attachment = base64_encode ( file_get_contents("name_of_file.bin" ) );
$headers.= "
Content-Type: application/bin; name='name_of_file.bin'
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
";
mail($email, $subject, "Some text to send as message", $headers);
?>