I don't quite understand what you mean. You can force a download suggestion to a user by using a code like this:
<?
$file = 'some_file.zip';
if(!$file)
{
die('File not found!');
}
else
{
header("Content-Description: File Transfer");
header("Content-Disposition: attachment; filename=$file");
header("Content-Type: application/zip");
header("Content-Transfer-Encoding: binary");
readfile($file);
}
?>
If you are talking about a resume like:
Joe started downloaded some_file.zip, and stopped half way. Now he wants to go back and download the rest for where he left off.
No, that is not possible, sorry.
Good Luck!
If you need further assistance/advice, feel free to contact me.