my @dat_files = <$bboard/*.dat>;
my %found = ();
foreach my $file ( @dat_files ) {
    open(DAT, $file) or die "$file: $!";
    while ( <DAT> ) {
        my @thread_data = split "|";
        if ( $thread_data[4] =~ m/\Q$in{$for}\E/i ) {
            $found{$thread_data[0]}++;
        }
    }
    close(DAT);
}