I believe the reason that the recursive call causes the error is that when you're inside the function, the function is not defined yet. Thus, the recursive call does not see the prototype and thus does not automatically pass the parameter by reference. (See also ichimunki's reply.)

You could probably fix that and keep the prototype (if you wanted, though it's probably best to ditch the prototype anyway) by changing your recursive call from:

GetSSNameFromFile ( $s_ParentFileName, 
                    $$rs_OutputFile, 
                    $$rs_RecurseLabel );
[download]

GetSSNameFromFile ( $s_ParentFileName, 
                    $$rs_OutputFile, 
                    $rs_RecurseLabel );
[download]

Don't quote me on that, though. I'm not 100% sure that would work (I didn't test it).

bbfu
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