I'd like to have a sub that returns success or failure on completion. I'd like the sub to take parameters, make changes to those parameters and pass the changed parameters back to the caller for use in the main body. What it the correct way to do it in Perl? Thanks. 
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;
}

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In reply to Parameter passing by Anonymous Monk

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