thanks for the reply. yeah, that is true re: "die". I was looking it over again, and ran into a possible problem:

if (scalar(@tmp_file_list) == 0) {
die("the directory is empty!");
}
else {
foreach (@tmp_file_list) {
if ($_ eq $lock_file) {
die("Transfer_helper is busy.");
}
}
}
[download]

-- if there is are no files in the dir, the script should exit (and not write the lock file.

I like the idea of creating a sub for managing the lock file. thanks