BEGIN {
    my( $dot, $up )= ( File::Spec->curdir(), File::Spec->updir() );

    sub SearchDirs {
        my( $path, $subdir )= @_;
        $path= File::Spec->catdir( $path, $subdir );
        chdir $subdir    or  die "Can't chdir, $path: $!\n";
        opendir D, $dot  or  die "Can't opendir, $path: $!\n";
        my @files= grep $_ ne $dot && $_ ne $up, readdir D;
        closedir D;
        for(  @files  ) {
            my $recurse=  ! -l $_  &&  -d _;
            # ...
            SearchDirs( $path, $_ )   if  $recurse;
        }
        chdir $up   or  die "Can't chdir .. from $path: $!\n";
    }
}