Lil' Dave said:
Another words, the written format using XP windows CD writing utility
never closes the session. Therefore, not genuine ISO 9660. If so, that
makes sense to me. But, there is a multisession extension for ISO 9660
(ISO 13480)/ECMA-168/ISO 9660 level 3) for re-writable CD media which
allow additions to a previously written CDRW in ISO 9660 format. File
removal is also allowed under this multisession extension, though its
virtual removal as the file data still exists on the CDRW media. That's
what XP is utilizing. But, what I think you're trying to say if another
OS without facility of reading such media, expecting standard ISO 9660
format, won't be able to read that media. Such as msdos boot media with a
msdos cd driver environment as one such example. Not multisession reading
capable...
There are so many flavours of CD writing standards that it is entirely
possible that one can get totally confused by the myriad. Once a CD has
been closed to conform with ISO 9660 (or it's many predecessors come to
that), it is never possible to add additional data later. The ability to
add further data relies on the Table of Contents being writen to an
otherwise unused part of the disc and a blank entry being left on the end of
it. The act of closing the disc writes the final table of contents to the
official area from which, of course, it cannot be removed.
However, with CD-RW media the possibility of removing it and overwriting it
becomes a possibility. CD-RW media was only ever intended to be erased as a
whole disc, but it is posible to erase parts of it, but only at the block
level because the CD-RW technology does not provide byte accurate erase.
The practical upshot is that like the packet incremental formats, adding
further data to an otherwise closed disc will work most of the time, but an
occasional erase/write will miss the intended target and trash the disc.
Windows XP does not support this type of adding additional data.
It should also be noted that the ability to read unclosed multisession discs
is supported entirely by the disc drive itself, so even the earliest DOS
based CD drivers will work with multisession discs.
Audio CDs can also be put together in multisession, but CD-Audio players
cannot play them until the disc is closed. Having said that players from
Marantz built since the Orange Book specification came into existence have
always been able to play unclosed discs.
I did find that Orange book does not support writable CD media beyond 80
minute duration. Also found in the ISO 9660 spec, there are 2 forms of
CD-ROM mode 2. One is for data, the other is for audio/video. The data
version is not normally used due to compatibility reasons. However, you
may be indeed referring to this as a compatibility problem with older CD
drives as noted here:
You are referring to the 2 subvariants Mode 2 Form 1 and Mode 2 Form 2. The
difference is that the latter format dispenses with redundancy error
correction to achieve a ~15% speed increase. This was considered acceptable
for video as minor errors can go un-noticed. It was used exclusively for
the white book Video-CD format. CD Audio uses its own red book format from
which all the other flavours are derived. The data version Mode 2 Form 1
was intended for use with discs that include both data and audio tracks and
was a workaround for the so called "do not play track 1" disks (which were
mode 1, but not known as such as there was no Mode 2 at this time) where
attempts to play the data on audio equipment could damage the amplifier and
speakers as the first track was always the data track.
The workaround was that as Mode 2 supported Orange Book (multisession), the
audio was placed in the first session and the data was placed in a second
session where audio players didn't know how to play it. Mode 2 was also
known as CD-XA (Compact Disc - Extended Architecture). Data can be written
in Mode 2 as it is not a requirement that the audio tracks be present. Many
current CD writing utilities no longer offer the option and burn exclusively
in Mode 2, though many offer the option of the 'joliet' extension.
