You could use references to achieve this. 

. . .
my_sub(\$handle);
. . .
sub my_sub{
    my $handle = shift;

    if (handle_not_valid($$handle)){
        $handle = \(new_handle());
    }

    ...
}

[download]

Regards,

PN5

In reply to Re: Changing value passed to sub by Prior Nacre V
in thread Changing value passed to sub by Anonymous Monk

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