sub get_filehandles {
    my $dir = shift;
    opendir my ($dh), $dir;

    my @fhs = map {
        my $fh;
        open( $fh, '<', "$dir/$_" ) ? $fh 
                                    : do { warn "$dir/$_: $!"; () }
    } grep { -f "$dir/$_" } readdir($dh);

    closedir $dh;
    return \@fhs;
}