I wrote a simple recursive routine which file globs a directory, saves all the entires in an array, and recursivly does the same for any sub dirs.. i noticed that a "TON" of memory was consumed, during the process.. and apon return , using Devel::Leak, many many blocks were still allocated..
Calling the same function again, did NOT accumulate any more blocks.. Ok, maybe Perl is reusing the memory.. fine.
So i thought, a recursive function, is just a nested call onto "ITSELF". Would the same memory consumption apply if Function A called Function B, and Function B called Function C? These are just nested calls, but not onto itself. I got back ZERO blocks allocated after Function A. As i wanted. As _should_ be.
So i assumed that nested calls were OK.. but just not on itself. (due to a memory not being immediately released)..
So Obi Wan, i now ask why. Why is memory allocation different when a nested calling function , calls itself, vs calling another function. Does perl have special code to deal with recursion?

Any and all replies are appreciated...

Below is my test code...

System : Win2k, ActiveState 5.6.1.

use strict;



sub cat($)
{
   my $var = shift;
   print "cat ($var)\n";

}

sub bat($)
{
   my $var=shift;
   print "bat ($var)\n";
   cat($var);

}

sub apple($)
{
   my $hello=shift;
   print "Apple ($hello)\n";
   bat($hello);
}


sub recurse($)
{
   my $count=shift;

   print "0Count = ($count)\n";
   if ($count >= 1)
   {
      undef($count);
      print "Leaving...\n";
      return;
   }
   $count++;
   recurse($count);
}

sub recurse1($)
{
   my $count=shift;

   print "Count1 = ($count)\n";
   if ($count >= 1)
   {
      undef($count);
      print "Leaving...\n";
      return;
   }
   $count++;
   recurse2($count);
}

sub recurse2($)
{
   my $count=shift;

   print "Count2 = ($count)\n";
   if ($count >= 1)
   {
      undef($count);
      print "Leaving...\n";
      return;
   }
   $count++;
}

print "GetAll Test\n";
   
   use Devel::Leak;
   my $handle;
   my $count = Devel::Leak::NoteSV($handle);
   print "Memory Count Start = ($count)\n";

   # this loop is here to test accumulation of memory..
   # by increasing the loop max, it does not accumulate
   #  more memory usage.. it _seems_ to reuse....the
   #  results do not change..
  for (my $xx=0; $xx< 1; $xx++)
  {
     recurse(0);       # leaky toilet
    # recurse1(0);    # no leak
    # apple(1);       # no leaks           
  }



  my $count1= Devel::Leak::CheckSV($handle); 
  my $diff = $count1- $count; 
      
  print "\nCount = ($count1)\n";
  print "Difference in Memory = ($diff)\n";

#=== END----
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