listing files inside txt file inside a directoy and reading its content

<?php
foreach (glob("/var/spool/asterisk/voicemail/device/$_GET[vm]/INBOX/*.txt") as $filename) {
    echo "$filename  path  <br><br>";
$vm_prop=file($filename);
foreach($vm_prop as $key=>$value) {
echo" $key => $value<br>";
}
}
?>