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- From: scotty@gagetalker.com (Scott Turner)
- Newsgroups: comp.sys.next.hardware
- Subject: Re: Foreign CD-ROM disks on NeXT
- Message-ID: <1992Sep11.065612.11854@gagetalker.com>
- Date: 11 Sep 92 06:56:12 GMT
- References: <92251.121431MKK2@psuvm.psu.edu>
- Sender: scotty@gagetalker.com
- Organization: L5 Computing
- Lines: 62
-
- In article <92251.121431MKK2@psuvm.psu.edu> <MKK2@psuvm.psu.edu> writes:
- |> I hope someone will fill in some gaps about CD-ROM for me and the rest of
- |> this group.
- |>
- |> As I understand it, the ISO CD-ROM format is some kind of hierarchical
- |> file system modeled after the one Unix offers (based on OS-9?). I presume
- |> that msdos, Mac, Unix, or NeXT must develop some kind of driver that
- translates
- |> to and from that format.
- |>
- |> Does this mean the data files on a CD-ROM will be available to NeXT's file
- |> viewer. For example, will the Great Works of Literature on a GWOL disk
- |> be readable? I know that the *software* for reading them will be useless.
- I
- |> am curious about the data.
- The structure of an ISO-9660 CD-ROM has more in common with the extent based
- filesystems in use on Cray super computers than it does with Unix or OS-9
- filesystems (and no, the unix filesystem is _not_ based on os-9, it's the other
- way around.)
-
- Strictly speaking the NeXT computers speak a sub-set of ISO-9660, all the
- filesystems supplied by NeXT have been found to be non-conforming on
- many points.
-
- This means that not all ISO-9660 discs work with the NeXT. Some in fact even
- lockup the NeXT when it attempts to mount them (you then must manually eject
- the disc and reboot.)
-
- Some discs appear to work in that you can scan them, but when you actually
- try to read files you'll get junk at the front of the files.
-
- Even dates aren't sacred, don't go betting the farm on a date you get from a
- NeXT about a file on an ISO-9660 CD-ROM, and come to think of it, the time
- can be off as well.
-
- But before this turns into a NeXT cashing article, I've used several Mac
- ISO-9660 filesystems that have locked up as well.
-
- The best ISO-9660 implementation I know of is MSCDEX.EXE for MS-DOS. This
- appears to be a near letter perfect ISO-9660 filesystem implementation.
-
- So to answer your question, it depends on the disc. You may be able to access
- the data, or you may not be able to. You'll have to try it and see. I
- personally have had success with many IBM PC titles (and if Soft PC will
- ever do Win3.1 I'd have even more success.) Don't forget about SoftPC and
- Executor, these products will sometimes allow you to use the machine specific
- retrieval engines to get at the data on the discs.
-
- And for those with Executor who have been eagerly awaiting 3.0 so that they
- can access Mac CD-ROMs... There's a gotcha, the NeXT checks for ISO-9660
- compliance before it checks for a Mac HFS. If you wanted to play with a disc
- such as one the "Selectware" discs you'll find that the NeXT mounts the
- ISO-9660 part of the disc, which contains only IBM PC software (which works
- great with Soft PC BTW) you can't get at the Mac software on the disc.
-
- So far I haven't been able to talk my NeXTs (one is not enough ;) into mounting
- the Mac HFS part of the disc (it'll play "Please insert disc" "Wrong disc"
- "Please insert disc" for as long as I care to play.)
-
- Pure Mac HFS CD-ROMs do mount under 3.0.
-
- Scotty
-