Not quite - I meant just to look for the .complete file was there, so you'd upload file_2009-02-12_1234.dat and then upload file_2009-12-1234.dat.complete once the first upload was done. You may even want to put a small amount of metadata in the .complete file, an md5 of the real file, for example. So the upload is something like

my $id = '2009-02-12-1234';
my $filename = "file-$id.dat";
my $local_file = "$src_dir/$filename";

# upload 'real' file
$ftp->put ( $local_file, $filename ) || die "can't upload: $!";

# it completed ok - upload the completion marker
$ftp->put ( $dummy_file, "$filename.complete" );
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And the watcher:

foreach my $file (@files) {
 # Only look for the 'upload complete' marker files
 next unless $file =~ /^(.*)\.complete$/;

 # extract the name of the 'real' file
 my $base_name = $1;

 # insert into db
 pqinsert( $file_dir . $base_name );

 # move real file into archive dir
 move( $file_dir . $base_name, $archive_dir . $base_name )
   || die "can't move: to $archive_dir - $!";

 # remove the 'complete' marker file
 unlink($file) || die "can't unlink $file - $!"
}
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HTH!