if ( defined($$keyptr) ) 
{
   my $datapos = $RSubtree{$curuser}{$$keyptr};
   if (     defined($datapos)       #update
        and GetDataRecord( $db, $keyptr, $dataptr, $datapos ) ) 
   {
       flock( $db->{btree}, LOCK_UN );
       return "";
    }  
 }