Could you explain why reading should increase the refcount? 
use Devel::Peek;
my $x = 3;
Dump $x;
fork;
Dump $x;
__END__
SV = IV(0x90e54bc) at 0x90ca648
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,IOK,pIOK)
  IV = 3
SV = IV(0x90e54bc) at 0x90ca648
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,IOK,pIOK)
  IV = 3
SV = IV(0x90e54bc) at 0x90ca648
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,IOK,pIOK)
  IV = 3

[download]
The refcount isn't changed, even though a variable is read from a forked process. And why should it? I see no need for that.

The matter is different when variables go out of scope: then their refcount is reduced, thus possibly modifying it before deallocating.

Update It's probably this you meant: 

use Devel::Peek;
my $x = 3;
Dump $x;
my $y = \$x;
Dump $x;
__END__
SV = IV(0x97634bc) at 0x9748648
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,IOK,pIOK)
  IV = 3
SV = IV(0x97634bc) at 0x9748648
  REFCNT = 2
  FLAGS = (PADBUSY,PADMY,IOK,pIOK)
  IV = 3

[download]

In reply to Re^2: WHY copying does happen (fork) by moritz
in thread WHY copying does happen (fork) by Anonymous Monk

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