--- In BMUGSouth@y..., "dticzon" <dave@l...> wrote:
> "Well I got it to burn to CD but it was easier on the PC. Maybe I'm
> doing it wrong on the Mac but I had to prepare the CD before the
> Mac would modify it and then had to move it to the burn symbol
> to get the file on the CD. In the mean time my CD burner kept
> ejecting the CD before I had time to move files on to the CD.
> Now the PC can't add files to the CD.
> What is going on????
> Do I need to make this some special format? Why didn't the mac
> or PC give me that option?"
> Can anyone explain this?
It's a difference in file systems.
With the Mac's HFS file system, you can set up and burn what you
want, but it has to be all all-at-once operation. The Mac OS gives
you a disc "image" and lets you change that as you will, then burns
that to the CD when you drag the image onto the burn symbol. The
built-in Mac OS support will only do this once to a CD, but you can
use programs like Toast to do this multiple times to the same CD,
giving you a disc that mounts with more than one icon on the desktop.
Each burning session is completely separate, like partitioning a hard
drive, and the files burned to a CD are considered permanent and
But the Windows file system for CDs, ISO-9660, works in a different
way. Instead of keeping the sessions separate, the last burned
session holds an updated file directory for everything on the CD. So
if an ISO-9660 CD gets burned multiple times, it still mounts with
only one icon. Windows XP is set up to exploit this. You can go in
to a CD and "remove" a file from it, or add a file to it, and Windows
will burn the directory info about those changes to the disc when
You're still limited by the available space on the disc, though.
Deleting individual files from a CD-RW disc does not recover the disc
space they used, and you must still erase the entire CD-RW when it's
Adaptec (now Roxio) had a program for Mac OS 8 called DirectCD that
offered similar functionality using a different method (packet
writing), but they apparently don't sell it anymore. There may be
similar programs still out there.