[slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Bernhard Rosenkraenzer]

Slightly OT, but I think it's about time to work on a solution rather than the 
flamewar. ;)

I've just released dvdrtools 0.3.1 
(http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools that 
(as the name indicates) adds support for writing to DVD-R and DVD-RW disks 
using purely Free Software, that tries to do things the Linux way ("dvdrecord 
dev=/dev/cdrom whatever.iso") without suggesting to use 2.4 kernels or even 
other operating systems, uses a standard make system, is maintained in a 
public svn repository, and does away with a lot of the libc 
functionality-clones found in cdrtools.

There are a lot more things to do to get CD/DVD writing where it should (and 
could) be -- if anyone else is interested in fixing the CD/DVD situation, 
you're more than welcome to join our team.

Best regards,
bero

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[David Gómez]

Hi Bernard,

On Feb 25 at 12:42:51, Bernhard Rosenkraenzer wrote:
> 
> I've just released dvdrtools 0.3.1 
> (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools that 
> (as the name indicates) adds support for writing to DVD-R and DVD-RW disks 
> using purely Free Software, that tries to do things the Linux way ("dvdrecord 
> dev=/dev/cdrom whatever.iso") without suggesting to use 2.4 kernels or even 
> other operating systems, uses a standard make system, is maintained in a 
> public svn repository, and does away with a lot of the libc 
> functionality-clones found in cdrtools.

Good ;). This is first useful post i see since the CD recording flamewar ;).

regards,

-- 
David Gómez                                      Jabber ID: davidge@jabber.org

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jesper Juhl]

On 2/25/06, David Gómez <david@pleyades.net> wrote:
> Hi Bernard,
>
> On Feb 25 at 12:42:51, Bernhard Rosenkraenzer wrote:
> >
> > I've just released dvdrtools 0.3.1
> > (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools that
> > (as the name indicates) adds support for writing to DVD-R and DVD-RW disks
> > using purely Free Software, that tries to do things the Linux way ("dvdrecord
> > dev=/dev/cdrom whatever.iso") without suggesting to use 2.4 kernels or even
> > other operating systems, uses a standard make system, is maintained in a
> > public svn repository, and does away with a lot of the libc
> > functionality-clones found in cdrtools.
>
> Good ;). This is first useful post i see since the CD recording flamewar ;).
>
I'll second that.
A very nice initiative indeed. Now lets just hope it stays maintained,
works well and that eventually distros will pick it up.

--
Jesper Juhl <jesper.juhl@gmail.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
Plain text mails only, please      http://www.expita.com/nomime.html

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Gene Heskett]

On Friday 24 February 2006 18:42, Bernhard Rosenkraenzer wrote:
>Slightly OT, but I think it's about time to work on a solution rather
> than the flamewar. ;)
>
>I've just released dvdrtools 0.3.1
>(http://www.arklinux.org/projects/dvdrtools/). It is a fork of
> cdrtools that (as the name indicates) adds support for writing to
> DVD-R and DVD-RW disks using purely Free Software, that tries to do
> things the Linux way ("dvdrecord dev=/dev/cdrom whatever.iso")
> without suggesting to use 2.4 kernels or even other operating
> systems, uses a standard make system, is maintained in a public svn
> repository, and does away with a lot of the libc
>functionality-clones found in cdrtools.
>
>There are a lot more things to do to get CD/DVD writing where it
> should (and could) be -- if anyone else is interested in fixing the
> CD/DVD situation, you're more than welcome to join our team.
>
>Best regards,
>bero

Thank you very much Bernard. Hopefully this will lead to real progress 
in this arena.

-- 
Cheers, Gene
People having trouble with vz bouncing email to me should add the word
'online' between the 'verizon', and the dot which bypasses vz's
stupid bounce rules.  I do use spamassassin too. :-)
Yahoo.com and AOL/TW attorneys please note, additions to the above
message by Gene Heskett are:
Copyright 2006 by Maurice Eugene Heskett, all rights reserved.

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jesper Juhl]

On 2/26/06, Luke-Jr <luke@dashjr.org> wrote:
> On Friday 24 February 2006 23:42, Bernhard Rosenkraenzer wrote:
> > I've just released dvdrtools 0.3.1
> > (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools
> > that (as the name indicates) adds support for writing to DVD-R and DVD-RW
> > disks using purely Free Software,
>
> also DVD+R/RW/DL, I hope?
>

And what about DVD-RAM drives? Any plans to support those?

> > that tries to do things the Linux way ("dvdrecord dev=/dev/cdrom
> > whatever.iso")
>
> Shouldn't that be "dvdrecord whatever.iso /dev/cdrom" or similar?

I'd agree, that would match 'cp', 'mv', 'ln' etc by having the source
first and destination second.


> Any plans to support growing an ISO fs (ala growisofs)? Maybe by simply
> including a modified growisofs using dvdrecord-libscg?


--
Jesper Juhl <jesper.juhl@gmail.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
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Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Luke-Jr]

On Friday 24 February 2006 23:42, Bernhard Rosenkraenzer wrote:
> I've just released dvdrtools 0.3.1
> (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools
> that (as the name indicates) adds support for writing to DVD-R and DVD-RW
> disks using purely Free Software,

also DVD+R/RW/DL, I hope?

> that tries to do things the Linux way ("dvdrecord dev=/dev/cdrom
> whatever.iso")

Shouldn't that be "dvdrecord whatever.iso /dev/cdrom" or similar?
Any plans to support growing an ISO fs (ala growisofs)? Maybe by simply 
including a modified growisofs using dvdrecord-libscg?

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jesper Juhl]

On 2/26/06, Luke-Jr <luke@dashjr.org> wrote:
> On Sunday 26 February 2006 13:29, Jesper Juhl wrote:
> > On 2/26/06, Luke-Jr <luke@dashjr.org> wrote:
> > > On Friday 24 February 2006 23:42, Bernhard Rosenkraenzer wrote:
> > > > I've just released dvdrtools 0.3.1
> > > > (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools
> > > > that (as the name indicates) adds support for writing to DVD-R and
> > > > DVD-RW disks using purely Free Software,
> > >
> > > also DVD+R/RW/DL, I hope?
> >
> > And what about DVD-RAM drives? Any plans to support those?
>
> My [limited] understanding of DVD-RAM drives was that they are basically
> removable block devices... you wouldn't need a recording program for that,
> you'd use it like a floppy.
>
I guess you are right. I haven't used a DVD-RAM device in a few years,
I just seem to recall that when I last used one on an AIX pSeries
machine I had to use some burner software to dump data on it - I may
remember wrong though.

--
Jesper Juhl <jesper.juhl@gmail.com>
Don't top-post  http://www.catb.org/~esr/jargon/html/T/top-post.html
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Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Luke-Jr]

On Sunday 26 February 2006 13:29, Jesper Juhl wrote:
> On 2/26/06, Luke-Jr <luke@dashjr.org> wrote:
> > On Friday 24 February 2006 23:42, Bernhard Rosenkraenzer wrote:
> > > I've just released dvdrtools 0.3.1
> > > (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools
> > > that (as the name indicates) adds support for writing to DVD-R and
> > > DVD-RW disks using purely Free Software,
> >
> > also DVD+R/RW/DL, I hope?
>
> And what about DVD-RAM drives? Any plans to support those?

My [limited] understanding of DVD-RAM drives was that they are basically 
removable block devices... you wouldn't need a recording program for that, 
you'd use it like a floppy.

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Bernd Petrovitsch]

On Sun, 2006-02-26 at 13:39 +0000, Luke-Jr wrote:
[...]
> My [limited] understanding of DVD-RAM drives was that they are basically 
> removable block devices... you wouldn't need a recording program for that, 
> you'd use it like a floppy.

Yes, that's basically the case.
However one uses usually[0] UDF as filesystem.

	Bernd

[0]: You can use ext2 or others too, but then you can't read it on other
     OSes withour support for such filesystems.
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jan Engelhardt]

>> > > I've just released dvdrtools 0.3.1
>> > > (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools
>> > > that (as the name indicates) adds support for writing to DVD-R and
>> > > DVD-RW disks using purely Free Software,
>> >
>> > also DVD+R/RW/DL, I hope?
>>
>> And what about DVD-RAM drives? Any plans to support those?
>
>My [limited] understanding of DVD-RAM drives was that they are basically 
>removable block devices... you wouldn't need a recording program for that, 
>you'd use it like a floppy.
>
Same goes for DVD+RW. One may want to use it in conjunction with pktcdvd 
for aligning and command queueing/iosched reasons.


Jan Engelhardt
-- 

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Sam Vilain]

Jan Engelhardt wrote:
>>>And what about DVD-RAM drives? Any plans to support those?
>>My [limited] understanding of DVD-RAM drives was that they are basically 
>>removable block devices... you wouldn't need a recording program for that, 
>>you'd use it like a floppy.
> Same goes for DVD+RW. One may want to use it in conjunction with pktcdvd 
> for aligning and command queueing/iosched reasons.

Can I mount a friendly challenge to that idea?

The reason being, I've got a DVD writer that supports DVD-RAM, and 
because I was curious I bought one.  The media is *hard sectored*.  That 
is, you look at the underneath and you see a series of concentric dots, 
each the same angular distance from each other.  I had presumed that 
these are to give the drive something big to key its read/write 
operations on.  Nice, except I don't think the media is compatible with 
a regular DVD drive.

DVD+RW, on the other hand, I just thought was a different surface 
technology (more expensive, higher quality) than DVD-RW.  There is 
nothing to help with the lead-in/lead-out problem that is why you have 
several megabytes of lead-in and lead-out per session on a multi-session 
disc.

But maybe I'm wrong here... if I could use a DVD+RW like a DVD-RAM I'd 
be very happy indeed.

Sam.

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Dick Streefland]

Bernhard Rosenkraenzer <bero@arklinux.org> wrote:
| I've just released dvdrtools 0.3.1 
| (http://www.arklinux.org/projects/dvdrtools/). It is a fork of cdrtools that 
| (as the name indicates) adds support for writing to DVD-R and DVD-RW disks 
| using purely Free Software, that tries to do things the Linux way ("dvdrecord 
| dev=/dev/cdrom whatever.iso") without suggesting to use 2.4 kernels or even 
| other operating systems, uses a standard make system, is maintained in a 
| public svn repository, and does away with a lot of the libc 
| functionality-clones found in cdrtools.

Good. So, we can finally fix this:

diff -pu dvdrtools-0.3.1/dvdrecord/scsi_cdr.c.orig dvdrtools-0.3.1/dvdrecord/scsi_cdr.c
--- dvdrtools-0.3.1/dvdrecord/scsi_cdr.c.orig	2006-02-15 03:47:41.000000000 +0100
+++ dvdrtools-0.3.1/dvdrecord/scsi_cdr.c	2006-02-27 16:24:10.000000000 +0100
@@ -2196,7 +2196,7 @@ EXPORT void printinq(SCSI *scgp, FILE *f
 	if (inq->add_len >= 31 ||
 			inq->info[0] || inq->ident[0] || inq->revision[0]) {
 		fprintf(f, "Vendor_info    : '%.8s'\n", inq->info);
-		fprintf(f, "Identifikation : '%.16s'\n", inq->ident);
+		fprintf(f, "Identification : '%.16s'\n", inq->ident);
 		fprintf(f, "Revision       : '%.4s'\n", inq->revision);
 	}
 }

-- 
Dick Streefland                      ////                      Altium BV
dick.streefland@altium.nl           (@ @)          http://www.altium.com
--------------------------------oOO--(_)--OOo---------------------------

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jan Engelhardt]

>> > > And what about DVD-RAM drives? Any plans to support those?
>> > My [limited] understanding of DVD-RAM drives was that they are
>> > basically removable block devices... you wouldn't need a recording
>> > program for that, you'd use it like a floppy.
>> Same goes for DVD+RW. One may want to use it in conjunction with pktcdvd
>> for aligning and command queueing/iosched reasons.
>
> Can I mount a friendly challenge to that idea?
>
I win, reiserfs on a dvd+rw:
  http://jengelh.hopto.org/GFX/dvdrw_r3mnt.jpg

> I had presumed that these are to give the drive
> something big to key its read/write operations on.  Nice, except I don't think
> the media is compatible with a regular DVD drive.
>
Yes. A 650 MB *CD*-RW (DVD-RW too?) formatted in packet mode only has like
500-something megabytes to allow for the sort of seeks required.
On DVD+RW, you get the full 4.3 GB (4.7 gB) AFAICS.

> DVD+RW, on the other hand, I just thought was a different surface technology
> (more expensive, higher quality) than DVD-RW.  There is nothing to help with
> the lead-in/lead-out problem that is why you have several megabytes of lead-in
> and lead-out per session on a multi-session disc.
>
> But maybe I'm wrong here... if I could use a DVD+RW like a DVD-RAM I'd be very
> happy indeed.
>
> Sam.
>
>

Jan Engelhardt
-- 

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Phillip Susi]

Jan Engelhardt wrote:
> Yes. A 650 MB *CD*-RW (DVD-RW too?) formatted in packet mode only has like
> 500-something megabytes to allow for the sort of seeks required.
> On DVD+RW, you get the full 4.3 GB (4.7 gB) AFAICS.
> 

DVD-RAM physically is formatted like a hard disk.  It is broken up into 
zones that hold different numbers of sectors which are individually and 
randomly read/writable.  CD/DVD+-RW media is organized as a single long 
groove that consists of an unbroken series of large blocks composed of 
small blocks with user and control data interleaved and error corrected. 
  It is for this reason that historically it could only be recorded from 
start to finish in one pass.

There are two modern techniques to allow pseudo random write access for 
all forms of CD/DVD +/- RW media.  These are packet mode, and mount 
rainier mode.  MRW mode formats the disk into 32 KB blocks made up of 
2048 byte sectors which are individually writable as far as the OS 
knows, because an MRW compliant drive is required to internally handle 
any required read/modify/write cycles to update the 32 KB blocks.  MRW 
mode also reserves some of the disk for sector sparing which the drive 
firmware also handles.  MRW mode is typically used on dvd+rw media. 
IIRC, this format typically "wastes" about 10% of the capacity of the 
medium.

The other technique is packet mode.  Packet mode formats the media into 
packets of sectors and each packet can be randomly rewritten.  The 
current default size is only 32 sectors per packet.  Each packet has 7 
sectors of linking loss so around 18% of the disk space is wasted.  I 
recently submitted a patch to pktcdvd and have some patches to the 
udftools package to support larger packet sizes.  A packet size of 128 
sectors reduces the waste to only 5.2%.

>> DVD+RW, on the other hand, I just thought was a different surface technology
>> (more expensive, higher quality) than DVD-RW.  There is nothing to help with
>> the lead-in/lead-out problem that is why you have several megabytes of lead-in
>> and lead-out per session on a multi-session disc.
>>
>> But maybe I'm wrong here... if I could use a DVD+RW like a DVD-RAM I'd be very
>> happy indeed.
>>
>> Sam.
>>
>>
> 
> Jan Engelhardt

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jan Engelhardt]

>> Yes. A 650 MB *CD*-RW (DVD-RW too?) formatted in packet mode only has like
>> 500-something megabytes to allow for the sort of seeks required.
>> On DVD+RW, you get the full 4.3 GB (4.7 gB) AFAICS.
>
> DVD-RAM physically is formatted like a hard disk.  It is broken up into zones
> that hold different numbers of sectors which are individually and randomly
> read/writable.  CD/DVD+-RW media is organized as a single long groove that
> consists of an unbroken series of large blocks composed of small blocks with
> user and control data interleaved and error corrected.  It is for this reason
> that historically it could only be recorded from start to finish in one pass.
>
> There are two modern techniques to allow pseudo random write access for all
> forms of CD/DVD +/- RW media.  These are packet mode, and mount rainier mode.
> MRW mode formats the disk into 32 KB blocks made up of 2048 byte sectors which
> are individually writable as far as the OS knows, because an MRW compliant
> drive is required to internally handle any required read/modify/write cycles to
> update the 32 KB blocks.  MRW mode also reserves some of the disk for sector
> sparing which the drive firmware also handles.  MRW mode is typically used on
> dvd+rw media. IIRC, this format typically "wastes" about 10% of the capacity of
> the medium.
>
I doubt that. 10% of a 4.3 GB disk are, well, roughly 430 MB, which would 
make df show 3.9 GB as mountpoint size, not 4.3 GB. [MB and GB are powers 
of 1024 here.]


Jan Engelhardt
-- 

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Bill Davidsen]

Jan Engelhardt wrote:
>>> Yes. A 650 MB *CD*-RW (DVD-RW too?) formatted in packet mode only has like
>>> 500-something megabytes to allow for the sort of seeks required.
>>> On DVD+RW, you get the full 4.3 GB (4.7 gB) AFAICS.
>> DVD-RAM physically is formatted like a hard disk.  It is broken up into zones
>> that hold different numbers of sectors which are individually and randomly
>> read/writable.  CD/DVD+-RW media is organized as a single long groove that
>> consists of an unbroken series of large blocks composed of small blocks with
>> user and control data interleaved and error corrected.  It is for this reason
>> that historically it could only be recorded from start to finish in one pass.
>>
>> There are two modern techniques to allow pseudo random write access for all
>> forms of CD/DVD +/- RW media.  These are packet mode, and mount rainier mode.
>> MRW mode formats the disk into 32 KB blocks made up of 2048 byte sectors which
>> are individually writable as far as the OS knows, because an MRW compliant
>> drive is required to internally handle any required read/modify/write cycles to
>> update the 32 KB blocks.  MRW mode also reserves some of the disk for sector
>> sparing which the drive firmware also handles.  MRW mode is typically used on
>> dvd+rw media. IIRC, this format typically "wastes" about 10% of the capacity of
>> the medium.
>>
> I doubt that. 10% of a 4.3 GB disk are, well, roughly 430 MB, which would 
> make df show 3.9 GB as mountpoint size, not 4.3 GB. [MB and GB are powers 
> of 1024 here.]
> 
Was that DVD recorded MtR or packet?


-- 
    -bill davidsen (davidsen@tmr.com)
"The secret to procrastination is to put things off until the
  last possible moment - but no longer"  -me

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Rob Sims]

[-- Attachment #1: Type: text/plain, Size: 2658 bytes --]

On Tue, Feb 28, 2006 at 01:58:34PM -0500, Phillip Susi wrote:
> Jan Engelhardt wrote:
> >Yes. A 650 MB *CD*-RW (DVD-RW too?) formatted in packet mode only has like
> >500-something megabytes to allow for the sort of seeks required.
> >On DVD+RW, you get the full 4.3 GB (4.7 gB) AFAICS.
 
> DVD-RAM physically is formatted like a hard disk.  It is broken up into 
> zones that hold different numbers of sectors which are individually and 
> randomly read/writable.  CD/DVD+-RW media is organized as a single long 
> groove that consists of an unbroken series of large blocks composed of 
> small blocks with user and control data interleaved and error corrected. 
>  It is for this reason that historically it could only be recorded from 
> start to finish in one pass.

While DVD-RAM has per-sector embossing of headers, the ECC size is
still 16 sectors, so writing any one sector requires a read-modify-write
pass.  

> There are two modern techniques to allow pseudo random write access for 
> all forms of CD/DVD +/- RW media.  These are packet mode, and mount 
> rainier mode.  MRW mode formats the disk into 32 KB blocks made up of 
> 2048 byte sectors which are individually writable as far as the OS 
> knows, because an MRW compliant drive is required to internally handle 
> any required read/modify/write cycles to update the 32 KB blocks.  MRW 
> mode also reserves some of the disk for sector sparing which the drive 
> firmware also handles.  MRW mode is typically used on dvd+rw media. 
> IIRC, this format typically "wastes" about 10% of the capacity of the 
> medium.

DVD+RW and theoretically DVD-RW support writing of 32K chunks randomly
on the disk.  DVD+RW has a tight tolerance on positioning (+/-16 bits)
and DVD-RW about 150 bytes.  Both rely on ECC to correct those bits,
though DVD+RW obviously eats less of the ECC budget.  Neither format
uses a special packet format.  The drives themselves are supposed to do
read-modify-write as required.

> The other technique is packet mode.  Packet mode formats the media into 
> packets of sectors and each packet can be randomly rewritten.  The 
> current default size is only 32 sectors per packet.  Each packet has 7 
> sectors of linking loss so around 18% of the disk space is wasted.  I 
> recently submitted a patch to pktcdvd and have some patches to the 
> udftools package to support larger packet sizes.  A packet size of 128 
> sectors reduces the waste to only 5.2%.
 
Fixed packet writing is only a CD attribute.

Using 128 sector packets will likely break UDF interchangeability, and
likely even some drive firmware.
-- 
Rob

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: [slightly OT] dvdrecord 0.3.1 -- and yes, dev=/dev/cdrom works ;)

[Jan Engelhardt]

>>>> Yes. A 650 MB *CD*-RW (DVD-RW too?) formatted in packet mode only has like
>>>> 500-something megabytes to allow for the sort of seeks required. On
>>>> DVD+RW, you get the full 4.3 GB (4.7 gB) AFAICS.
>>>>
>>> DVD-RAM physically is formatted like a hard disk.  It is broken up into
>>> zones that hold different numbers of sectors which are individually and
>>> randomly read/writable.  CD/DVD+-RW media is organized as a single long
>>> groove that consists of an unbroken series of large blocks composed of
>>> small blocks with user and control data interleaved and error corrected. 
>>> It is for this reason that historically it could only be recorded from
>>> start to finish in one pass.
>>> 
>>> There are two modern techniques to allow pseudo random write access for all
>>> forms of CD/DVD +/- RW media.  These are packet mode, and mount rainier
>>> mode. MRW mode formats the disk into 32 KB blocks made up of 2048 byte
>>> sectors which are individually writable as far as the OS knows, because an
>>> MRW compliant drive is required to internally handle any required
>>> read/modify/write cycles to update the 32 KB blocks.  MRW mode also
>>> reserves some of the disk for sector sparing which the drive firmware also
>>> handles.  MRW mode is typically used on dvd+rw media. IIRC, this format
>>> typically "wastes" about 10% of the capacity of the medium.
>>> 
>> I doubt that. 10% of a 4.3 GB disk are, well, roughly 430 MB, which would
>> make df show 3.9 GB as mountpoint size, not 4.3 GB. [MB and GB are powers of
>> 1024 here.]
>> 
> Was that DVD recorded MtR or packet?
>
Hm. I'd say `cdrecord ... -format` (whatever that does), if required.
Otherwise just write to it (mkfs/etc.).


Jan Engelhardt
--