Why does a broken pdf-file arrive when sent using php?

Question

PHP

Hello, I've been working on a problem for half a day. There is a source pdf-file on my site, it must be sent attached to the letter. The file finds, opens, reads, but when trying to open the resulting file, adobe reader swears that the file is damaged or has not been decoded, etc.
I checked the file from the site - clean, working. Tell me what am I doing wrong?
PS chunk_split () set, just in this version I already try without it. No difference. Source file 56 kb, received - 80 (78 without chunk) kb

<?php 
$to  = "[email protected]" ;  

$subject = "Подтверждение заказа"; 

//$message = file_get_contents('../files/accept_'.$_POST['id'].'.php');


$file=fopen('../files/orderpdf_'.$_POST['id'].'.pdf','rb');
$name='../files/orderpdf_'.$_POST['id'].'.pdf';
$attachment=fread($file, filesize($name));
fclose($file);
$attachment=base64_encode($attachment);


unlink('../files/orderpdf_'.$_POST['id'].'.pdf');



$headers  = "MIME-Version: 1.0 \r\n";
$headers .= "Content-Type: multipart/mixed; boundary=pdfnik \r\n";
$headers .= "charset=utf-8 \r\n";
$file= basename('../files/orderpdf_'.$_POST['id'].'.pdf');


$body  = "--pdfnik\n";   
$body .= "Content-Type: application/octet-stream; ";
$body .= "name=".basename('../files/orderpdf_'.$_POST['id'].'.pdf')."\n";
$body .= "Content-Transfer-Encoding:base64n\n";
$body .= "Content-Disposition:attachment; filename=\"$file\"\n\n";
$body .= $attachment;
$body .= "pdfnik--\n";

mail($to, $subject, $body, $headers); 
?>

Answer 1

There's a typo at the end, it should be like this
body .= "Content-Transfer-Encoding:base64\n\n";