Hello, My goal is to wait-for and recognize when files have changed their file extension. I will be placing 5 files in a directory. Another program will modify those files and change their file extension from .prc to .prd. When all files have their extensions changed to .prd I know that I then need to do something. I'm looking for suggestions as to the best way to go about this.

Here's what I've got so far (untested): 
sub wait_for_files {
   my $files = shift;

   my %not_changed_yet = %$files;
   while () {
      last if (! %not_changed_yet);
      for my $file (keys(%$files)) {
         if (-s $files->{$file}) { # file has .prd
            delete $not_changed_yet{$file};
         }
      }
   }
}

[download]
I'm sure that could be improved by an order of magnitude :-) How would you do it?

In reply to Waiting For File Extension Changes by Murpher

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