Php mail send with attachment - php

Question

I have written code for sending mail with attachment , i am getting mail but wil noname file with icon. I am providing path to file name and rest details to send mail.
I have written code for this migth be there is header problem i am not gettin g this problem.
Code:
$file = $path.$filename;
$file_size = filesize($file);
$handle = fopen($file, "r");
$content = fread($handle, $file_size);
fclose($handle);
$content = chunk_split(base64_encode($content));
$uid = md5(uniqid(time()));
$header = "From: ".$from_name." <".$from_mail.">\r\n";
$header .= "Reply-To: ".$replyto."\r\n";
$header .= "MIME-Version: 1.0\r\n";
$header .= "Content-Type: multipart/mixed; boundary=\"".$uid."\"\r\n\r\n";
$header .= "This is a multi-part message in MIME format.\r\n";
$header .= "--".$uid."\r\n";
$header .= "Content-type:text/plain; charset=iso-8859-1\r\n";
$header .= "Content-Transfer-Encoding: 7bit\r\n\r\n";
$header .= $message."\r\n\r\n";
$header .= "--".$uid."\r\n";
$header .= "Content-Type: application/octet-stream; name=\"".$filename."\"\r\n"; // use different content types here
$header .= "Content-Transfer-Encoding: base64\r\n";
$header .= "Content-Disposition: attachment; filename=\"".$filename."\"\r\n\r\n";
$header .= $content."\r\n\r\n";
$header .= "--".$uid."--";
if (mail($mailto, $subject, "", $header)) {
echo "mail send ... OK"; // or use booleans here
} else {
echo "mail send ... ERROR!";
}