SOLVED BY MYSELF: 
opendir OF, $oldFolder or die "\nCannot open dir $oldFolder: $!\n";
    
    
while (    my  $name=readdir OF) {
   next if  $name =~ /^\./ ;     
   next if -f "$oldFolder/$name"; 

   print $name;
   print "\n";


}

closedir OF;

[download]
---------------------------- Why this control fails? 
while (my $name=readdir OF) {
      next if  ( ($name =~ /^\./ )||(-f $name) ); 

      #must print only directories

      print $name;
      print "\n";

}

[download]
the control on ".",".." is correct; but it is always a directory, also when $name is a file. In that context also "-d $name" returns true also when it is a file not directory

In reply to check if it is a file or directory by saintex

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