If you return concatenated first and second argument, why pass a third argument to the function? If you want to pass the third argument "by reference," pass a reference to the scalar (remember that Perl only passes parameters by value). Then you will be able to say something like 
$$returnstring = $a . $b;

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Also, you might want to re-phrase your question.

In reply to Re: sub functions, and strings by dmitri
in thread sub functions, and strings by bdawg613

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