xorrecord - Emulation of CD/DVD/BD program cdrecord by program xorriso
[ options ] dev=device [track_source]
writes preformatted data to CD, DVD, and BD media.
It understands some options of program cdrecord from cdrtools by Joerg
Schilling. Its implementation is part of program xorriso which shares no
source code with cdrtools, but rather makes use of libburn for communicating
with the drive.
Another, more complete cdrecord emulator is program cdrskin
the same burn functions as xorrecord
, but is able to burn audio CDs and
to handle CD-TEXT.
is a standard out of the SCSI family which defines the interaction
between computers and optical drives. Since more than a decade all CD, DVD, or
BD recorders obey this standard regardless by what bus cabling they are
attached to the computer. libburn relies on this standard compliance and on
the capability of the operating system to perform SCSI transactions over the
particular bus cabling.
is a data region on an optical disc which usually gets written
in a single sweep. It contains at least one Track
which is a contiguous
string of readable blocks. xorrecord
produces a single session with a
single data track which consists of blocks with 2048 bytes each. It chooses
the write mode automatically according to media type, medium state, and option
On CD media there are other track types, like audio, and particular write modes
like TAO and SAO. CD and DVD- media can put more than one track into a
session. Some of these features can be addressed by program cdrskin
MMC describes several recordable media types
which roughly form two
Sequentially recordable media
are CD-R, CD-RW, DVD-R, DVD-R DL, DVD-RW,
DVD+R, DVD+R DL, BD-R. Except DVD-R DL they can store more than one session if
there is still unwritten space and if the previous session was written with
. CD-RW and DVD-RW can be blanked in order to be re-usable
are DVD-RAM, DVD+RW, formatted DVD-RW, BD-RE. They
offer a single session with a single track for random access writing. There is
no need to blank overwritable media before re-use.
DVD-RW media are sold in sequentially recordable state but can be formatted once
to become overwritable. See options blank=format_overwrite
If ISO 9660 filesystems are to be stored on overwritable media, then it is
possible to emulate multiple sessions, by using option
. In this case, the need for blanking before
re-use is emulated too.
Drive preparation and addressing:¶
The drives, CD, DVD, or BD burners, are accessed via file addresses which are
specific to libburn and the operating system. Those addresses get listed by a
run of xorrecord --devices
or xorriso -device_links
On GNU/Linux and FreeBSD, the user needs rw-permission for the device file. On
Solaris, the user needs r-permission and privilege "sys_devices",
which is usually gained by running xorrecord
via command pfexec.
These permissions resp. privileges are needed already for listing a drive. So it
might be necessary to get the overview as superuser resp. via pfexec.
does not perform cdrecord option -scanbus and does not accept
the addresses of form Bus,Target,Lun which are told by -scanbus. If support
for these addresses is necessary, consider to use program cdrskin.
It is possible to let xorrecord
work on emulated drives. Their addresses
begin by prefix "stdio:" followed by a file address. The emulated
media behavior depends on the file type. See man xorriso for details.
If standard output is chosen as emulated drive, then all program result texts,
which usually appear on standard output, will get redirected to standard
Relation to program xorriso:¶
is actually a command mode of program xorriso
gets entered either by xorriso command "-as cdrecord" or by starting
the program by one of the names "xorrecord", "cdrecord",
"wodim", or "cdrskin".
This command mode can be left by argument "--" which leads to generic
xorriso command mode. See man xorriso
for its description. Other than
in xorriso command mode, the sequence of the cdrecord emulation options does
not matter. All pending actions get performed in a fixed sequence before the
program run ends resp. before cdrecord emulation ends.
- Addressing the drive:
- Print the list of accessible CD, DVD, or BD drives to standard output.
Drives might be inaccessible if the user lacks of permissions to use them
or if the drive is in use by another program.
Each accessible drive is shown by a line like:
0 -dev '/dev/sr0' rwrw-- : 'TSSTcorp' 'CDDVDW SH-S203B'
The libburn address of this drive is '/dev/sr0'. 'TSSTcorp' is the name of
the vendor (in this case: Toshiba Samsung Storage Technologies
Corporation), 'CDDVDW SH-S203B' is the model name (in this case: a DVD
Afterwards end emulation without performing any further drive
- Set the libburn address of the drive to be used.
E.g. on GNU/Linux: dev=/dev/sr0
E.g. on FreeBSD: dev=/dev/cd0
E.g. on Solaris: dev=/dev/rdsk/c2t2d0s2
See also above "Drive preparation and addressing".
The medium in the drive should not be mounted or be otherwise in use.
This option will only get into effect if a track source, a blank= option, or
a drive inquiry option is given. Else it will lead to a SORRY event and
normally cause a non-zero exit value.
- Inquiring drive and media:
- Print to standard output: vendor, model name, and firmware revision of the
- Print unconditionally that the drive supports burnfree, SAO, and TAO. Also
print the output of option -inq.
- Print the output of -checkdrive, the most capable profile of the medium in
the drive, the list of profiles which are supported by the drive, whether
it is erasable (i.e. can be blanked), the media manufacturer, and the
medium product name.
Profiles are usage models, which are often tied to a particular media type
(e.g. CD-RW), but may also apply to a family of media. E.g. profile CD-ROM
applies to all CD media which contain data.
- Print a table of content of the medium in the drive. The output is not
compatible to cdrecord option -toc, but rather the one of xorriso
command -toc. It lists the address, vendor, model name, and firmware
revision of the drive.
About the medium it tells product name and manufacturer, whether there is
already content written, and if so, whether the medium is closed or
appendable. Appendable media can take another session. The amount of
readable and writable data is told. If there are sessions, then their
start block address and size is reported. If a session contains an ISO
9660 filesystem, then its Volume Id is reported. If the medium is
writable, then the next writable block address is reported.
If not option --grow_overwriteable_iso is given or no ISO 9660 file
system is present on the medium, then overwritable media are reported as
being blank. This is due to the fact that they can be written from scratch
without further preparation, and that MMC does not distinguish between
data written by the most previous burn run and older data which have not
been overwritten by that burn run. Consequently, these media are reported
with 0 readable blocks, although all their writable blocks normally are
- Print the argument text for option -C of programs mkisofs, genisoimage, or
xorrisofs. It consists of two numbers separated by a comma.
The first number tells the first block of the first track of the last
recorded session. This is also the address used by default when operating
systems mount a medium with e.g. ISO 9660 filesystem.
The second number tells the next writable address, where xorrecord
will begin to write the next session.
This option is only valid for written, appendable media. In all other cases
it will yield no output text but will abort the program with non-zero exit
- Settings for the burn run:
A burn run requires exactly one track source address argument, which tells from
where to read the data wich shall be put into the upcomming session. The
medium state must be either blank or appendable.
Track source may be "-" for standard input or the address of a
readable file of any type except directories. Nearly all media types accept a
track source with unpredictable byte count, like standard input or named
pipes. Nevertheless, DVD-R DL and DVD-RW blanked by mode deformat_quickest
demand exact in-advance reservation of the track size, so that they either
need to be read from a source of predictable length, or need to be accompanied
by option tsize=
or by option -isosize
Several options expect a size value as argument. A number with a trailing letter
"b" or without a trailing letter is a plain byte count. Other
trailing letters cause multiplication of the given number by a scaling factor:
"k" or "K" = 1024 , "m" or "M" = 1024k ,
"g" or "G" = 1024m , "s" or "S" = 2048
E.g. tsize=234567s means a size of 234567 * 2048 = 480393216 bytes.
- Blank a CD-RW or DVD-RW to make it re-usable from scratch. Format a
DVD-RW, DVD+RW, DVD-RAM, BD-R, or BD-RE if not yet formatted.
This operation normally makes any recorded data on the medium unreadable. It
is combinable with burning in the same run of xorrecord, or it may
be performed without a track source, leaving the medium empty.
The mode given with blank= selects the particular behavior:
Try to make the media ready for writing from scratch. If it needs formatting,
then format it. If it is not blank, then try to apply blank=fast. It is a
reason to abort if the medium cannot assume thoroughly writeable state, e.g.
if it is a non-blank write-once.
This leaves unformatted DVD-RW in unformatted blank state. To format DVD-RW use
blank=format_overwrite. Blank unformatted BD-R stay unformatted.
(Note: blank=as_needed is not an original cdrecord option.)
Blank an entire CD-RW or an unformatted DVD-RW.
Minimally blank an entire CD-RW or blank an unformatted DVD-RW.
Like blank=all but with the additional ability to blank overwriteable DVD-RW.
This will destroy their formatting and make them sequentially recordable.
(Note: blank=deformat is not an original cdrecord options)
Like blank=deformat but blanking DVD-RW only minimally. This is faster than full
blanking but yields media incapable of writing tracks of unpredicatable size.
Multi-session will not be possible either.
(Note: blank=deformat_quickest is not an original cdrecord option.)
Format a DVD-RW to "Restricted Overwrite". The user should bring some
Format unformatted DVD+RW, BD-RE or blank BD-R to their default size. It is not
mandatory to do this with DVD+RW and BD-RE media, because they will get
formatted automatically on the first write attempt.
BD-R media may be written in unformatted state. This keeps disabled the
replacement of bad blocks and enables full nominal write speed. Once BD-R
media are written, they cannot be formatted any more.
For re-formatting already formatted media or for formatting with non-default
size, use program xorriso
with command -format
(Note: blank=format_overwrite is not an original cdrecord options)
Print a short overview of blank modes to standard error output.
Afterwards end emulation without performing any drive operation.
- This option keeps CD, unformatted DVD-R[W], DVD+R, or BD-R appendable
after the current session has been written. Without it the disc gets
closed and may not be written any more - unless it is a -RW and gets
blanked, which causes loss of its content.
This option cannot be applied to DVD-R DL and DVD-RW which were blanked by
In order to have all filesystem content accessible, the eventual ISO-9660
filesystem of a follow-up session needs to be prepared in a special way by
the filesystem formatter program. mkisofs, genisoimage, and xorrisofs
expect particular info about the situation which can be retrieved by
xorrecord option -msinfo.
With overwriteable DVD or BD media, -multi cannot mark the end of the
session. So when adding a new session, this end has to be determined from
the payload. Currently only ISO-9660 filesystems can be used that way. See
- Try to perform the drive operations without actually affecting the
inserted media. There is no warranty that this will work with a particular
combination of drive and media. Blanking is prevented reliably, though. To
avoid inadverted real burning, -dummy refuses burn runs on anything but
CD-R[W], DVD-R[W], or emulated stdio-drives.
- Wait until input data is available at stdin or EOF occurs at stdin. Only
then begin to access any drives.
One should use this if xorrisofs is working at the end of a pipe where the
feeder process reads from the drive before it starts writing its output
into xorrisofs. Example:
xorrisofs ... -C 0,12800 -M /dev/sr0 ... | \
xorrecord dev=/dev/sr0 ... -waiti -
This option works even if standard input is not the track source. If no
process is piping in, then the Enter key of your terminal will act as
trigger for xorrecord. Note that this input line will not be
consumed by cdrskin if standard input is not the track source. It will end
up as shell command, usually.
- Announce the exact size of the track source. This is necessary with DVD-R
DL media and with quickest blanked DVD-RW, if the size cannot be
determined in advance from the track source. E.g. if it is standard input
or a named pipe.
If the track source does not deliver the predicted amount of bytes, the
remainder of the track is padded with zeros. This is not considered an
error. If on the other hand the track source delivers more than the
announced bytes then the track on media gets truncated to the predicted
size and xorrecord exits with non-zero value.
- Try to obtain the track size from the content of the track source. This
works only if the track source bears an ISO 9660 filesystem. Any other
track source content will cause the burn run to abort.
If the track source is not a regular file or block device, then this option
will work only if the program's fifo size is at least 64k. See option
- Add the given amount of trailing zeros to the upcomming track. This
feature can be disabled by size 0. Default is 300 kB in order to work
around a problem with GNU/Linux which often fails to read the last few
blocks of a CD track which was written in write mode TAO. TAO is used by
xorrecord if the track size cannot be predicted or if the CD medium
is not blank but appendable.
- The same as padsize=0.
- The same as padsize=15s. This was once sufficient with older GNU/Linux
kernels. Meanwhile one should at least use padsize=128k, if not
- Explicitely announce that the track source shall be recorded as data
track, and not as audio track. This option has no effect with
xorrecord, because there is no support for other track formats
- Explicitely demand that write type TAO shall be used for CD, or
Incremental for DVD-R. Normally the program will choose the write type
according to the given medium state, option -multi, and track source.
Demanding it explicitely prevents the start of a write run, if it is not
appropriate to the situation.
- Explicitely demand that write type SAO shall be used for CD, or DAO for
DVD-R. This might prevent the write run, if it is not appropriate to the
- Alias of -sao.
- Set the size of the program fifo buffer to the given value rather than the
default of 4m.
The fifo buffers a temporary surplus of track source data in order to
provide the drive with a steady stream during times of temporary lack of
track source supply.
Other than cdrecord, xorrecord enables drive buffer underrun protection by
default and does not wait with writing until the fifo is full for a first
time. On very old CD drives and slow computers, this might cause aborted
burn runs. In this case, consider to use program cdrskin for CD
burning. DVD and BD drives tolerate buffer underrun without problems.
The larger the fifo, the longer periods of poor source supply can be
compensated. But a large fifo can deprive the operating system of read
cache for better filesystem performance.
- Set the write speed. Default is 0 = maximum speed. Speed can be given in
media type dependent x-speed numbers or as a desired throughput per second
in MMC compliant kB (= 1000) or MB (= 1000 kB). Media x-speed factor can
be set explicity by appending "c" for CD, "d" for DVD,
"b" for BD. "x" is optional.
706k = 706kB/s = 4c = 4xCD
5540k = 5540kB/s = 4d = 4xDVD
If there is no hint about the speed unit attached, then the medium in the
drive will decide. Default unit is CD, 1x = 176,400 raw bytes/second. With
DVD, 1x = 1,385,000 bytes/second. With BD, 1x = 4,495,625 bytes/second.
MMC drives usually activate their own idea of speed and take the speed value
given by the burn program only as a hint for their own decision.
- Eject the drive tray after alll other work is done.
- Program version and verbosity:
- Print to standard output a line beginning by
"Cdrecord 2.01-Emulation Copyright"
and further lines which report the version of xorriso and its supporting
libraries. They also state the license under which the program is
provided, and disclaim any warranty, to the extent permitted by law.
Afterwards end emulation without performing any drive operation.
- Increase program verbosity by one level. There are four verbosity levels
from nearly silent to debugging verbosity. The both highest levels can be
enabled by repeated -v or by -vv resp. -vvv.
- Log SCSI commands and drive replies to standard error. This might be of
interest if xorrecord and a particular drive or medium do not
cooperate as expected, or if you just want to know how libburn interacts
with the drive. To understand this extremely verbous log, one needs to
read SCSI specs SPC, SBC, and MMC.
Please do not add such a log to a bug report on the first hand, unless you
want to point out a particular deviation from said specs, or if you get
asked for this log by a maintainer of xorrecord who feels in charge
for your bug report.
- Print a sparse list of program options to standard error and declare not
to be cdrecord.
Afterwards end emulation without performing any drive operation.
- Options not compatible to cdrecord:
- Only if used as first command line argument this option prevents reading
and interpretation of startup files. See section FILES below.
- Enable emulation of multi-session writing on overwriteable media which
contain an ISO 9660 filesystem. This emulation is learned from growisofs
-M but adapted to the usage model of
xorrisofs -C -M | xorrecord -waiti -multi -
for sequential media.
--grow_overwriteable_iso does not hamper the use of true multi-session
media. I.e. it is possible to use the same xorrecord options with
both kinds of media and to achieve similar results if ISO 9660 filesystem
images are to be written. This option implies option -isosize and
therefore demands that the track source is a ISO 9660 filesystem image.
With overwriteable media and no option blank=fast|all present it expands an
eventual ISO 9660 filesystem on media. It is assumed that this image's
inner size description points to the end of the valuable data.
Overwriteable media with a recognizable ISO 9660 size will be regarded as
appendable rather than as blank. I.e. options -msinfo and -toc will work.
-toc will always show a single session with its size increasing with every
added ISO 9660 image.
- Mode "on" requests that compliance to the desired speed setting
is preferred over management of write errors. With DVD-RAM and BD this can
bring effective write speed near to the nominal write speed of the media.
But it will also disable the automatic use of replacement blocks if write
errors occur. It might as well be disliked or ignored by the drive.
If a number is given, then error management stays enabled for all byte
addresses below that number. Any number below 16s is the same as
- Linux specific: Set the number of bytes to be transmitted with each write
operation to DVD or BD media. Tracks get padded up to the next multiple of
this write size. A number of 64 KB may improve throughput with bus systems
which show latency problems. The default depends on media type, option
stream_recording=, and on compile time options.
- Set the block address on overwritable media where to start writing the
track. With DVD+RW, DVD-RAM or BD-RE, byte_offset must be aligned to 2 kiB
blocks, but better is 32 kiB on DVD and 64 kiB on BD. With formatted
DVD-RW 32 kiB alignment is mandatory.
Other media are not suitable for this option.
- Set the number of bytes after which to force output to emulated stdio:
drives. This forcing keeps the memory from being clogged with lots of
pending data for slow devices. Default "on" is the same as
"16m". Forced output can be disabled by "off".
Overview of examples:¶
Get an overview of drives and their addresses
Get info about a particular drive or loaded media
Prepare CD-RW or DVD-RW for re-use, BD-R for bad block handling
Format DVD-RW to avoid need for blanking before re-use
De-format DVD-RW to make it capable of multi-session again
Write a single ISO 9660 filesystem image
Write multiple ISO 9660 sessions
Write ISO 9660 session on-the-fly
Write compressed afio archive on-the-fly
Get an overview of drives and their addresses:¶
$ xorrecord --devices
$ xorrecord dev=/dev/sr0 -atip -toc --grow_overwriteable_iso
Prepare CD-RW or DVD-RW for re-use:¶
$ xorrecord -v dev=/dev/sr0 blank=as_needed -eject
Format DVD-RW to avoid need for blanking before re-use:¶
$ xorrecord -v dev=/dev/sr0 blank=format_overwrite -eject
This command may also be used to format BD-R media before first use, in order to
enable handling of write errors. Several hundred MB of spare blocks will be
reserved and write runs on such media will perform with less than half nominal
De-format DVD-RW to make it capable of multi-session again:¶
$ xorrecord -v dev=/dev/sr0 blank=deformat
Write a single ISO 9660 filesystem image:¶
$ xorrecord -v dev=/dev/sr0 speed=12 fs=8m \
blank=as_needed -eject padsize=300k my_image.iso
Write multiple ISO 9660 sessions:¶
This is possible with all media except minimally blanked DVD-RW and DVD-R DL,
which cannot do multi-session.
The first session is written like in the previous example, except that option
-multi is used. It will contain the files of hard disk directory ./tree1 under
the ISO 9660 directory /dir1:
$ xorrisofs -o image_1.iso -J -graft-points /dir1=./tree1
$ xorrecord -v dev=/dev/sr0 speed=12 fs=8m \
-multi --grow_overwriteable_iso \
blank=as_needed -eject padsize=300k image_1.iso
For the second session xorrisofs needs to know the -msinfo numbers of the
medium. Further it will read data from the medium by using the system's
read-only CD-ROM driver.
It is advised to load the tray manually or via dd by the CD-ROM driver, rather
than letting xorrecord do this by its own SCSI driver. Many system CD-ROM
drivers do not take notice of xorrecord's activities.
$ dd if=/dev/sr0 count=1 >/dev/null 2>&1
Now get the -msinfo numbers:
$ m=$(xorrecord dev=/dev/sr0 -msinfo)
and use them with xorrisofs to add ./tree2 to the image as /dir2:
$ xorrisofs -M /dev/sr0 -C $m -o image_2.iso \
-J -graft-points /dir2=./tree2
Now burn the new session onto the same medium. This time without blanking:
$ xorrecord -v dev=/dev/sr0 speed=12 fs=8m \
-multi --grow_overwriteable_iso \
-eject padsize=300k image_2.iso
Operating systems which mount this medium will read the superblock of the second
session and show both directories /dir1 and /dir2.
Write ISO 9660 session on-the-fly:¶
It is possible to combine the run of xorrisofs
pipeline without storing the ISO 9660 image as file on hard disk:
$ xorrisofs -M /dev/sr0 -C $m \
-J -graft-points /dir2=./tree2 \
| xorrecord -v dev=/dev/sr0 speed=12 fs=8m \
-waiti -multi --grow_overwriteable_iso \
-eject padsize=300k -
This is also the main use case of program xorriso
itself, where this run
would look like:
$ xorriso -dev /dev/sr0 -joliet on -speed 12 -fs 8m \
-map ./tree2 /dir2 -commit_eject all
Write compressed afio archive on-the-fly:¶
This is possible with all media except minimally blanked DVD-RW and DVD-R DL.
Since the compressed output stream is of very variable speed, a larger fifo is
advised. Nevertheless, this example is not suitable for very old CD drives
which have no underrun protection and thus would abort the burn run on
temporary data shortage.
$ find . | afio -oZ - | \
xorrecord -v dev=/dev/sr0 speed=12 fs=64m \
-multi padsize=300k -
afio archives do not contain references to absolute data block addresses. So
they need no special precautions for multi-session. One may get the session
start addresses by option -toc, and then use dd option skip= to begin reading
at one of those addresses. E.g. for listing its content:
$ dd if=/dev/sr0 bs=2048 skip=64046 | afio -tvZ -
afio will know when the end of the archive is reached.
If not --no_rc is given as the first argument then xorrecord
startup to read and execute lines from the following files:
The files are read in the sequence given here, but none of them is required to
exist. The lines are not interpreted as xorrecord
options but as
commands. See man xorriso.
- For generic xorriso command mode
- Formatting track sources for xorrecord:
- xorrisofs(1), mkisofs(8), genisoimage(8),
- Other programs which burn sessions to optical media
- growisofs(1), cdrecord(1), wodim(1),
To report bugs, request help, or suggest enhancements for xorriso
send electronic mail to the public list <email@example.com>. If more
privacy is desired, mail to <firstname.lastname@example.org>.
Please describe what you expect xorriso
to do, the program arguments
resp. commands by which you tried to achieve it, the messages of
, and the undesirable outcome of your program run.
Expect to get asked more questions before solutions can be proposed.
Thomas Schmitt <email@example.com>
Copyright (c) 2011 - 2013 Thomas Schmitt
Permission is granted to distribute this text freely. It shall only be modified
in sync with the technical properties of xorriso. If you make use of the
license to derive modified versions of xorriso then you are entitled to modify
this text under that same license.
is in part based on work by Vreixo Formoso who provides libisofs
together with Mario Danic who also leads the libburnia team. Thanks to Andy
Polyakov who invented emulated growing, to Derek Foreman and Ben Jansens who
once founded libburn.
Compliments towards Joerg Schilling whose cdrtools served me for ten