I really don't know anything about perl on 64-bit systems, but in the absence of any other responses...

What do you get if you do

my $x = 'hello world!';
my $px = pack 'P', $x;
print length $px; # Ought to print '8' on a 64-bit system

print unpack 'p', $px; # Should print 'Hello world!'
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If that works, then Perl is packing the pointers correctly and you are 'using them wrong'. Sorry for such a vague diagnosis:)

If that doesn't work, then you maybe have discovered a bug in 64-bit perl and should raise it to p5p.

Thanks for helping!
Your code does the right thing and works. I think Perl5/OpenBSD 64bit does not like this pointer for its IOCTLs ...
BTW this is the whole code:

  my $tocentry;
  my $toc="";
  my $size=0;
  for(@tracks) {
    $toc.="        ";
    $size+=8;
  }

  if($os =~ /BSD/) {
    my $size_hi=int($size / 256);
    my $size_lo=$size & 255;

    if($BIG_ENDIAN) {
      # in 32bit: $tocentry=pack "CCCCP8l", $CDROM_MSF,0,$size_hi,$siz
+e_lo,$toc;
      $tocentry=pack "CCCCP", $CDROM_MSF,0,$size_hi,$size_lo,$toc; # c
+urrent version
    } else {
      $tocentry=pack "CCCCP8l", $CDROM_MSF,0,$size_lo,$size_hi,$toc;
    }
    ioctl(CD, $CDROMREADTOCENTRY, $tocentry) or die "cannot read track
+ info [$!] [$device]";
  }
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Should I post in p5p?

I wouldn't run off to p5p just yet...but that's me, you may get better and/or quicker answers there from someone who has a 64-bit system to play with. That said, of you go there, do so via the perl5porters@perl.com list rather than perlbug as what my snippet did prove is that this isn't a perlbug. Your just using it wrong:)

One thing I notice is that you are attempting to pack a 16-bit numeric value by splitting it into two 8-bit values and using 'CC' and switching the bytes around to account for the endianess of the current system.

A) I think that you are doing this wrongly.

B) There is no need for you to do this sort of thing yourself. pack already has that smarts built-in, although it requires you to pass along some clue bats to enable it.

pack has format specifiers 'n' and 'v' which will pack a 16-bit unsigned value from a number in a perl scalar, in either big-endian or little-endian format respectively.

Also, you don't show where or how your $BIG_ENDIAN variable is being set, but you should take a look at the Config package which is a part of the standard distribution. In particular

use Config;

print $Config{ byteorder };
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will tell you the order of the bytes on the current system. It will probably return somethng like '12345678' or '78563412' on your system.

Hope this helps.

Update: You might also want to check out perlpacktut. It's about the best tutorial i've seen on pack. You may have a local copy, but it is fairly recent addition to the doc set,so the link above may help.

---

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller
If I understand your problem, I can solve it! Of course, the same can be said for you.

that works on both openbsd/sparc64 and openbsd/alpha (both 64-bit systems, the first being big endian and the second being little endian). on the openbsd/i386 system it prints '4' and 'hello world!' as expected.