Maybe I missing something here and if so, please just follup with what I am missing. You say ListCategories works. What is wrong with
  1. replacing the print with $output_string .=
  2. changing the function to this 
    {
   my $output_string;
   sub DoListCategories {
     $output_string = "";
     ListCategories(@_);
   }
   sub ListCategories {
     #Just as you had it with the change in 1 above
   }
}

    [download]
    Note the outer braces so $output_string is "private" to these two functions.
  3. Changing the calls in the main program from ListCategories to DoListCategories
This saves you from having to re-write working code.

HTH, --traveler

In reply to Re: Collecting data in a recursive routine. by traveler
in thread Collecting data in a recursive routine. by Anonymous Monk

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