CD-ROM w/ISC

Hans Oey hans at mo.hobby.nl
Fri Apr 5 05:27:24 AEST 1991


lumpi at dobag.in-berlin.de (Joern Lubkoll) writes:

>joe at eng3.UUCP (Joe LaRocque) writes:

>>Do you know of a driver for a CD-ROM (Microsoft format) for ISC 2.+ ?
>>Is it possible to access the CD-ROM from Vpix?

>>Any assist would be appreciated.
>I'm also very interested in hearing about it !

The MSDOS device drivers for my CD-ROM were unusable from
VPIX because they use DMA. I wrote a Unix device driver
for my Philips CM110 CD-ROM and was able to open it,
seek to any sector and read it. As the CD-ROM had the
usual High Sierra (ISO-9660?) file system I was able
to write some code to copy any CD file into a Unix directory.
Then the CD access software from within VPIX was fooled
to use that directory: 14 ms access time instead of > 500ms :-)
Alas, I can't afford buying 660MB hard disks for each CD.

Unix System V, release 3.2, got a file system switch so that
you can mount a foreign file system (mount -f dos). Because
SVR4 has vnodes, this mechanism won't be used much longer
and I don't expect much support. But it must be very easy
to add the High Sierra format since it doesn't need any writing.

DOES ANYBODY OUT THERE HAS ANY DOCUMENTATION
ABOUT THE SVR3 FILE SYSTEM TABLES?
-- 
Hans Oey
hans at mo.hobby.nl



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