s/first/primary/;

Try this for all screens

{
    use Wx;
    my $count = Wx::Display::GetCount();
    my $dc = 0;
    while( $dc < $count ){
        my $disp = Wx::Display->new( $dc );

        my $rect = $disp->GetGeometry;
        print "$dc $disp ", join 'x', map { $rect->$_ } qw[ GetWidth G
+etHeight ];
        print "\n";
        print "$dc $disp ", $disp->GetName, "\n";
        print "$dc $disp ", ' IsPrimary ', $disp->IsPrimary, "\n";
        print "\n";
        $dc++;
    }
}


__END__
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