# not portable -- linux only
sub getwinsize {
    my $winsize = "\0" x 8;
    my $TIOCGWINSZ = 0x40087468;
    if (ioctl(STDOUT, $TIOCGWINSZ, $winsize)) {
        ($rows, $cols, $xpixel, $ypixel) = unpack('S4', $winsize);
    } else {
        $cols = 80;
    }
}