RETURN VALUE
       Usually, on success zero is returned.  A few ioctl() requests  use  the
       return  value as an output parameter and return a non-negative value on
       success.  On error, -1 is returned, and errno is set appropriately.

##</code><code>##

 require 'sys/ioctl.ph';
    die "no TIOCGWINSZ " unless defined &TIOCGWINSZ;
    open(TTY, "+</dev/tty")                     or die "No tty: $!";
    my $ret=ioctl(TTY, &TIOCGWINSZ, $winsize='');
    printf "ret num=%d, retstring=%s\n",$ret,$ret;

    unless ($ret) {
            die sprintf "$0: ioctl TIOCGWINSZ (%08x: $!)\n", &TIOCGWIN
+SZ;
    }
    ($row, $col, $xpixel, $ypixel) = unpack('S4', $winsize);
    print "(row,col) = ($row,$col)";
    print "  (xpixel,ypixel) = ($xpixel,$ypixel)" if $xpixel || $ypixel;

    print "\n";

##</code><code>##

ret num=0, retstring=0 but true
(row,col) = (79,80)

##</code><code>##

my @ar=(1,2,3,4,5,6);
my ($x,$y,$z)=@ar;