Re: [Libcdio-devel] Re: Submission of new mmc function for libcdio

[Rocky Bernstein]

Thanks for the clarification and information. Will keep this in mind going
forward.

On Sun, Jan 31, 2010 at 1:39 PM, Thomas Schmitt <address@hidden> wrote:

> Hi,
>
> > Are the states:
> >    1. writing from scratch (blank)
> >    2. overwritable (but not necessarily blank)
> >    3. erased (and now blank) but not known new media
> > distinguishable using MMC
>
> I don't know about a method to distinguish 1
> and 3.
> Number 2 is distinguishable by profile number
> and probably by Disc Status of READ DISC
> INFORMATION as proposed by Frank.
>
> The decision to declare them blank is due to
> libburn traditions with CD. I would advise to
> distinguish them from really blank media in
> libcdio.
>
> Especially because these media can be used on
> Linux and FreeBSD without any special burn
> program. Just open device file, use lseek,
> read and write as normal.
>
>
> > Also, although I can see why libburn may find it useful to combine drive
> and
> > media status here, I'm not sure it would be advisable from the standpoint
> of
> > a developing general library.
>
> A strict distinction between drive and media
> might be not really comprehensive.
> E.g:
> The state BURN_DISC_EMPTY (= no media loaded) is
> quite a hybrid of drive and media property.
> Nevertheless i would include it in a list of
> media states.
> BURN_DISC_UNSUITABLE can happen e.g. if you put
> a blank CD-R into a DVD-ROM drive. The drive
> might tell you profile 0x0000 and not more.
> The media is not to blame. But not usable either.
>
>
> Most of MMC exposes the drive as a thing that
> has current features and a current profile.
> One has to dig quite deep to get to real media
> info like the DVD Book type or the Blu-ray
> Disk Type Identifier.
> (READ DISC STRUCTURE Format Code 0 delivers
> different formats for DVD and BD.
> MMC-5, 6.23.3.2.1 for DVD, 6.23.3.3.1 for BD)
>
>
> Have a nice day :)
>
> Thomas
>
>
>
>