Your only serious error is that you do not copy the hash into your subroutine when you get the other arguments. Note that you do have to dereference the reference. 
    my($key);
    my($val);
    my(%subHash);
    $key = shift @_;
    $val = shift @_;
    %subHash = %{shift @_};

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With this addition, your subroutine will make a copy of the existing hash, add a key/value pair to the copy, and return the copy. Your main program overwrites the old hash with the new one. I believe that this is what you intend.
Bill

In reply to Re: How to populate a HASH using a FOR loop to a FUNCTION by BillKSmith
in thread How to populate a HASH using a FOR loop to a FUNCTION by Gigiux

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