FTP_PUT, without overwriting existing files?

[listenmirndt]

I just want to be able to use ftp_put, but if the file already exists, not overwrite

here is the function that i am using, found on another website, works good, just need to modify it somehow so that existing files are not overwritten...

function ftp_putAll($conn_id, $src_dir, $dst_dir) {
        $d = dir($src_dir);
        while($file = $d->read()) { // do this for each file in the directory
                if ($file != "." && $file != "..") { // to prevent an infinite loop
                        if (is_dir($src_dir."/".$file)) { // do the following if it is a directory
                                if (!ftp_nlist($conn_id, $dst_dir."/".$file)) {
                                        ftp_mkdir($conn_id, $dst_dir."/".$file); // create directories that do not yet exist
                                }

                            ftp_putAll($conn_id, $src_dir."/".$file, $dst_dir."/".$file); // recursive part
                    } else {

                            $upload = ftp_put($conn_id, $dst_dir."/".$file, $src_dir."/".$file, FTP_BINARY); // put the files
                            if (!$upload) echo 'FTP upload failed!';
                                    echo ". ";
                    }
            }
    }
$d->close();
}