Why pass references in - why not just pass the scalars $x and $y? 
my ($x, $y);
if (fn($x, $y)) {
    die "fn() failed\n";
}

# do stuff with $x and $y...
exit 0;

sub fn
{
    my ($fn_x, $fn_y) = @_;
    ($fn_x, $fn_y) = ('x', 'y');

    my $rc = 0;
    $rc = 1 if $fn_x ne 'x'; # never happens, just an example

    return 0;
}

[download]
The only change I made was to change the call - instead of passing references in, just pass the scalars. You aren't changing the values of the variables in the subroutine - I can't see any reason why you would want to pass the references instead of the actual scalar values.

In reply to Re: Parameter passing by hmerrill
in thread Parameter passing by Anonymous Monk

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