Re: [Libcdio-help] reading the whole 2352 bytes from every type of sector

[R. Bernstein]

Matheus Izvekov writes:
 > On Tue, Mar 4, 2008 at 1:16 AM, R. Bernstein <address@hidden> wrote:
 > > Sorry, but I'm not sure I understand the lingo you are using and
 > >  what you want to do. Probably libcdio doesn't do what you want, but
 > >  there may be code that does something similar to what you want.
 > 
 > The problem I'm having can be reproduced in the utility cd-read.
 > Try reading a data sector using -m audio. I can't get the whole 2352 bytes
 > of the sector this way. 

Not all CD-ROMs and libcdio drivers will allow one to even read a
track as an audio sector if that track isn't listed in the TOC as
being an audio or red-book track. On the other hand, obviously, some
do. Bit if this doesn't do what you imagine, this should not be
surprising.

 > Then I use mmc_read_cd to do that, but then this
 > doesnt work on image files.

The mmc_* routines issue multimedia commands to a CD-ROM drive. Some
support for simulating CD-ROM behavior is tolerated but there is only
so far one can go pretending an image file is a CD-ROM. With some
effort, possibly one can jimmy up routines to always return false if
you ask if the media has been changed, but what does it mean to
"eject" a CD image file? (I think here libcdio returns a status like
"not supported")

 > 
 > The weird thing is that doing the same thing on a image file, 
 > cddio_read_sector
 > doesnt return an error, but gives some garbage instead.

Perhaps an error should be returned. The weird thing to me is that you
seem to want to just try any a read of a sector in audio format,
whether it makes sense or not. There is a saying: garbage in, garbage
out.