# First, build the hash of names+size of all the local files
my %local_file;
for my $filename (@return2) {
    $filename =~ /^(.*)_(20\d{6})$/
        or die "Couldn't find date part in filename '$filename'";
    my $remote_name = $1;
    my $local_size = -s $filename;
    my $key = join "|", $remote_name, $local_size;
    $local_file{ $key } = $filename;
};

for my $remote_file (@remoteFilelist) {
    my $remote_size = -s $remote_file;
    my $key = join "|", $remote_name, $remote_size;
    if (! exists $local_file{ $key }) {
        print "$remote_file does not exist locally, or exists locally but with the wrong size.\n";
    } else {
        print "$remote_file exists locally as $local_file{ $key }\n";
    }
};