Cannot write attachment to disk

I've used the following code to parse a raw email:

use ZBateson\MailMimeParser\Message;

$message = Message::from($_POST['rawEmail']);

foreach ($message->getAllAttachmentParts() as $ind => $part) {
    $filename = $part->getHeaderParameter(
        'Content-Type',
        'name',
        $part->getHeaderParameter(
             'Content-Disposition',
             'filename',
             '__unknown_file_name_' . $ind
        )
    );
    file_put_contents($filename, $part->getContent());
}

But it only writes some of the attachment data to the file, not all of it. This works on my localhost but it does not work on my server (bluehost shared hosting).

I've looked at the examples on the library's website and tried a number of other ways to write the file besides file_put_contents($filename, $part->getContent());. Such as:

$out = fopen($filename, 'w+');
$str = $part->getBinaryContentResourceHandle();
$contents = stream_get_contents($str);
fwrite($out, $contents);
fclose($str);
fclose($out);

and

$out = fopen($filename, 'w+');
$str = $part->getBinaryContentResourceHandle();
stream_copy_to_stream($str, $out);
fclose($str);
fclose($out);

and

$stream = $part->getContentStream();
$part->saveContent($filename);

But none write all of the data to a file on the server. Any help appreciated! Thanks in advance!

zbateson / mail-mime-parser

Cannot write attachment to disk #150