Hi I'm trying to understand variable scope. I'm used to C where a variable created inside a subroutine is on the stack and it disappears when the subroutine returns. However in this perl example, I create a variable inside a subroutine (a hash called %hsh). I then assign the address of this hash to a global variable and then set some values inside this hash. When the subroutine ends, I would expect that the global variable would point to something that has disappeared. However the printout succeeds in printing the correct values from that hash. Why is this. I'm basically concerned that everything I'm creating inside these subroutines is not getting cleaned-up. 
my $gptr;

a1();
print "v1=" . $gptr->{'v1'} . "\n";
exit(0);

sub a1
{
   my %hsh;

   $gptr = \%hsh;

   $gptr->{'v1'} = 10;
   $gptr->{'v2'} = 20;
}

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In reply to Do subroutine variables get destroyed? by bt101

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