sub get_dup
{
    croak "Usage: \$db->get_dup(key [,flag])\n"
        unless @_ == 2 or @_ == 3 ;
 
    my $db        = shift ;
    my $key       = shift ;
    my $flag	  = shift ;
    my $value 	  = 0 ;
    my $origkey   = $key ;
    my $wantarray = wantarray ;
    my %values	  = () ;
    my @values    = () ;
    my $counter   = 0 ;
    my $status    = 0 ;
 
    # iterate through the database until either EOF ($status == 0)
    # or a different key is encountered ($key ne $origkey).
    for ($status = $db->seq($key, $value, R_CURSOR()) ;
	 $status == 0 and $key eq $origkey ;
         $status = $db->seq($key, $value, R_NEXT()) ) {
 
        # save the value or count number of matches
        if ($wantarray) {
	    if ($flag)
                { ++ $values{$value} }
	    else
                { push (@values, $value) }
	}
        else
            { ++ $counter }
     
    }
 
    return ($wantarray ? ($flag ? %values : @values) : $counter) ;
}