cdrecord(1)cdrecord(1)NAMEcdrecord - Records audio or data compact discs (CDs) from a master
SYNOPSIScdrecord [-general options] [-dev=device]... [-track options] [track1 .
. . trackn]
GENERAL OPTIONS
General options must be entered before any track file name or track
option. Retrieves and prints out the ATIP (absolute time in pregroove)
information of a CD recordable or CD rewritable media. With this
option, cdrecord tries to retrieve the ATIP info. If the actual drive
does not support to read the ATIP info, it may be that only a reduced
set of information records or even nothing is displayed. Only a limited
number of MMC compliant drives support reading the ATIP info.
If cdrecord is able to retrieve the lead-in start time for the
first session, it tries to decode and print the manufacturer
information from the media. Blanks a CD-RW and exits or blanks
a CD-RW before writing. The blanking type may be one of the fol‐
lowing: Blanks the entire disk. This may take a long time. Min‐
imally blanks the disk. This results in erasing the PMA, the TOC
and the pregap. Displays a list of possible blanking types.
Blanks the last session. Blanks a track. Blanks the tail of a
track. Uncloses last session. Unreserves a reserved track.
If used together with the -force flag, this option may be used
to blank CD-RW disks that otherwise cannot be blanked. Note that
you may need to specify -blank=all because some drives do not
continue with certain types of bad CD-RW disks. Note also that
cdrecord does its best if the -force flag is used, but it
finally depends on the drive's firmware whether the blanking
operation succeeds or not. Checks if a driver for the current
drive is present and exits. If the drive is a known drive,
cdrecord uses exit code 0. Sets disk-at-once mode. This cur‐
rently only works with MMC drives that support non-raw Session
At Once mode. Set the debug value to # (with -debug=#) or
increment the debug level by one (with -d). Specifying -dd is
equal to -debug=2. This may help to find problems while opening
a driver for libscg as well as with sector sizes and sector
types. Using -debug slows down the process and may be the reason
for a buffer underrun. Sets the default pregap size for all
tracks except track number 1. This option currently only makes
sense with the TEAC drive when creating track-at-once disks
without the 2 second silence before each track. This option may
not be available in future. Sets the SCSI target for the CD-
Recorder (see notes above). A typical device specification is
-dev=6,0. If a filename must be provided together with the
numerical target specification, the filename is implementation-
specific. The correct filename in this case can be found in the
system-specific manuals of the target operating system. On a
FreeBSD system without CAM support, you need to use the control
device (that is, /dev/rcd0.ctl). A correct device specification
in this case may be -dev=/dev/rcd0.ctl:@.
On Linux, drives connected to a parallel port adapter are mapped
to a virtual SCSI bus. Different adapters are mapped to differ‐
ent targets on this virtual SCSI bus.
If no dev option is present, cdrecord tries to get the device
from the CDR_DEVICE environment.
'If the argument to the -dev= option does not contain the char‐
acters ,, /, @ or :, it is interpreted as an label name that may
be found in the file /etc/default/cdrecord. See the FILES sec‐
tion for more information. Uses a user-supplied driver name for
the device. To get a list of possible drivers use -driver=help.
The reason for the existence of this option is to allow users to
use cdrecord with drives that are similar to supported drives
but not known directly by cdrecord. Use this option with extreme
care. If a wrong driver is used for a device, the possibility of
creating corrupted disks is high. The minimum problem related to
a wrong driver is that the -speed or -dummy does not work.
There is a special driver entry in the list: cdr_simul. This
driver is designed to make timing tests at any speed or timing
tests for drives that do not support the -dummy option. The sim‐
ulation driver implements a drive with a buffer size of 1MB that
can be changed with the CDR_SIMUL_BUFSIZE environment variable.
The simulation driver correctly simulates even a buffer underrun
condition. If the -dummy option is present, the simulation is
not aborted in case of a buffer underrun. Sets driver-specific
options. The options are specified with a comma-separated list.
To get a list of valid options use -driveropts=help together
with the checkdrive option. Currently only the burnproof option
is implemented to support Buffer Underrun Proof writing with
drives that use the Sanyo BURN-Proof technology. The CD-
Recorder goes through all steps of the recording process, but
the laser is turned off during this procedure. It is recommended
to run several tests before actually writing to a compact disk
if the timing and load response of the system is not known.
Ejects disk after doing the work. Some devices (such as Philips)
need to eject the medium before creating a new disk. Doing a
-dummy test and immediately creating a real disk would not work
on these devices. The disk is only fixated (that is, a TOC for
a CD-Reader is written). This may be used if for some reason the
disk has been written but not fixated. This option currently
does not work with old TEAC drives (CD-R50S and CD-R55S). Does
not fixate the disk after writing the tracks. This may be used
to create an audio disk in steps. An unfixated disk usually
cannot be used on a non CD-writer type drive but there are audio
CD players that are able to play such a disk. Forces command to
continue on some errors. This option currently implements some
tricks that allow you to blank out bad CD-RW disks. Sets the
fifo (ring buffer) size to #. You may use the same method as in
dd(1). The number representing the size is taken in bytes unless
otherwise specified. If a number is followed directly by the
letter b, k, m, s or f, the size is multiplied by 512, 1024,
1024*1024, 2048 or 2352 respectively. If the size consists of
numbers separated by x or *, multiplication of the two numbers
is performed. Thus -fs=10x63k species a fifo size of 630 kBytes.
The size specified by the -fs= argument includes the shared mem‐
ory that is needed for administration. This is at least one page
of memory. If no -fs= option is present, cdrecord tries to get
the fifo size value from the -CDR_FIFOSIZE environment. The
default fifo size is currently 4 MB.
The fifo is used to increase buffering for the real-time writing
process. It allows the system to run a pipe from mkisofs
directly into cdrecord. If the fifo is active and a pipe from
mkisofs into cdrecord is used to create a CD, cdrecord aborts
prior to doing any modifications on the disk if mkisofs dies
before it starts writing. The recommended fifo size is between 4
and 32 MBytes. As a rule of thumb, the fifo size should be at
least equal to the size of the internal buffer of the CD-
Recorder and no more than half of the physical amount of RAM
available in the machine. If the fifo size is big enough, the
fifo statistics prints a fifo empty count of zero and the fifo
min fill is not below 20%. It is not wise to use too much space
for the fifo. If you need more than 8 MB to write a CD on an
idle machine, your machine is either underpowered, has hardware
problems or is misconfigured. If you have buffer underruns or
similar problems and observe a zero fifo empty count, you have
hardware problems. The fifo size in this case is sufficient.
Ignores the known size of the medium. This option should be used
with extreme care; it exists only for debugging purposes and
should not be used for other reasons. It is not needed to write
disks with more than the nominal capacity. Does an inquiry for
the drive, prints the inquiry information, and exits. Tells the
-scg driver to modify the kernel debug value while SCSI commands
are running. Loads the media and exits. This only works with a
tray loading mechanism but seems to be useful when using the
Kodak disk transporter. Sets the Media Catalog Number of the CD
to med_cat_nr. Retrieves multisession information in a form
suitable for mkisofs 1.10 or later.
This option only makes sense with a CD that contains at least
one closed session and is appendable (not yet finally closed).
Some drives create error messages if you try to get the multi‐
session information for a disk that is not suitable for this
operation. Allows multisession CDs to be made. Use only for
recording multisession CDs. This flag needs to be present on all
sessions of a multisession disk, except when you want to create
a session that is the last session on the media. The fixation
allows the CD-Recorder to append additional sessions later. This
is done by generating a table of contents with a link to the
next program area. Media generated in this way is not 100% com‐
patible to manufactured CDs, except for CDplus.
If this option is present, the default track type is CD-ROM XA
mode 2. The Sony drives have no hardware support for -CD-ROM XA
mode 2. You have to specify the -data option in order to create
multisession disks on these drives.
Because cdrecord does not have a coder for converting data sec‐
tors to audio sectors, you need to force CD-ROM sectors by
including the -data option if you want to record a multisession
disk in DAO/SAO mode. Not all drives allow multisession CDs in
DAO/SAO mode. Sets packet writing mode. This is an experimen‐
tal interface. Sets the packet size to #, which forces fixed-
packet mode. This is an experimental interface. Prints the
drive capabilities for SCSI-3/mmc compliant drives as obtained
from mode page 0x2A. Values marked with kB use 1000 bytes as
kilobyte, values marked with KB use 1024 bytes as Kilobyte.
Scans all SCSI devices on all SCSI busses and prints the inquiry
strings. This option may be used to find the SCSI address of the
CD-Recorder on a system. The numbers printed out as labels are
computed as bus * 100 + target Does not print out a status
report for failed SCSI commands. Sets the speed factor of the
writing process to #, an integer, representing a multiple of the
audio speed. This is about 150 KB/s for CD-ROM and about 172
KB/s for CD-Audio. If no -speed option is present, cdrecord
tries to get the speed value from the CDR_SPEED environment. If
your drive has problems with -speed=2 or -speed=4, you should
try -speed=0. Sets the default SCSI command timeout value to #
seconds. The default SCSI command timeout is the minimum timeout
used for sending SCSI commands. If a SCSI command fails due to a
timeout, you may try to raise the default SCSI command timeout
above the timeout value of the failed command. If the command
runs correctly with a raised command timeout, report the better
timeout value and the corresponding command to the author of the
program. If no -timeout option is present, a default timeout of
40 seconds is used. Retrieves and prints out the table of con‐
tents or PMA of a CD. With this option, cdrecord works with CD-R
drives and with CD-ROM drives. Uses *.inf files to overwrite
audio options. If this option is used, the pregap size informa‐
tion is read from the *.inf file that is associated with the
file that contains the audio data for a track. Increments the
level of general verbosity by one. This displays the progress of
the write process. Increments the verbose level in the SCSI
command transport by one. This helps to debug problems that
occur in the CD-Recorder during the write process. If you get
incomprehensible error messages, use this option for more
detailed output. -VV shows data buffer content. Using the -V or
-VV option slows down the process and may cause a buffer under‐
run. Prints version information and exits. Waits for input to
become available on standard input before trying to open the
SCSI driver. This allows cdrecord to read its input from a pipe
even when writing additional sessions to a multisession disk.
When writing another session to a multisession disk, mkisofs
needs to read the old session from the device before writing
output. This cannot be done if cdrecord opens the SCSI driver at
the same time.
TRACK OPTIONS
Track options may be mixed with track file names. If this flag is
present, all subsequent tracks are written in CD-DA (similar to Red
Book) audio format. The file with data for these tracks should contain
stereo, 16-bit digital audio with 44100 samples/s. The byte order
should be the following: MSB left, LSB left, MSB right, LSB right, MSB
left and so on. The track should be a multiple of 2352 bytes. It is not
possible to put the master image of an audio track on a raw disk
because data is read in multiple of 2352 bytes during the recording
process.
If a filename ends in or the file is considered to be a struc‐
tured audio data file. The cdrecord command assumes that the
file in this case is a Microsoft file and extracts the audio
data from the files by skipping over the non-audio header infor‐
mation. In all other cases, cdrecord only works correctly if the
audio data stream does not have any header. Because many struc‐
tured audio files are not an integral number of blocks (1/75th
second) in length, it is often necessary to specify the -pad
option as well. The cdrecord command recognizes that audio data
in a file is stored in Intel (little-endian) byte order, and
automatically byte-swaps the data if the CD recorder requires
big-endian data. The cdrecord command rejects any audio file
that does not match the Red Book requirements of 16-bit stereo
samples in pcm coding at 44100 samples/second.
Using other structured audio data formats as input to cdrecord
usually works if the structure of the data is the structure
described above (raw pcm data in big-endian byte order). How‐
ever, if the data format includes a header, you hear a click at
the start of a track.
If neither -data nor -audio have been specified, cdrecord
defaults to -audio for all filenames that end in or and to -data
for all other files. If this flag is present, all subsequent
tracks are written in CDI format. The data is a multiple of 2048
bytes. If this flag is present, all subsequent tracks are writ‐
ten in CD-ROM mode 1 (Yellow Book) format. The data is a multi‐
ple of 2048 bytes. The file with track data should contain an
ISO-9660" or "Rock Ridge" filesystem image (see mkisofs for more
details). If the track data is an UFS filesystem image, fragment
size should be set to 2 KB or more to allow CR-drives with 2 KB
sector size to be used for reading.
If no other flag is present, -data is the default.
If neither -data nor -audio have been specified, cdrecord
defaults to -audio for all filenames that end in or and to -data
for all other files. Sets an index list for the next track. An
index list is a comma separated list of numbers counting from
index 1. The first entry in this list must contain a 0; the fol‐
lowing numbers must be an ascending list of numbers (counting in
1/75 seconds) that represent the start of the indices. An index
list in the form: 0,7500,15000 sets index 1 to the start of the
track, index 2 to 100 seconds from the start of the track and
index 3 to 200 seconds from the start of the track. Uses the
ISO-9660 file system size as the size of the next track. This
option is needed if you want to read the image of a track from a
raw disk partition or on a master CD. In the first case the
option -isosize is needed to limit the size of the CD to the
size of the ISO filesystem. In the second case the option -iso‐
size is needed to prevent cdrecord from reading the two run-out
blocks that are appended by each CD-recorder in track-at-once
mode. These two run-out blocks cannot be read and would cause a
buffer underrun that would cause a defective copy. Do not use
this option if cdrecord reads the track data from stdin. This
option currently cannot be used to determine the size of a file
system if the multisession option is present. Sets the Interna‐
tional Standard Recording Number for the next track to Circumam‐
bulate. If this flag is present, all subsequent tracks are
written in CD-ROM mode 2 format. The data is a multiple of 2048
bytes. If the track is a data track, 15 sectors of zeroed data
is added to the end of this and each subsequent data track. In
this case, the -pad option is superseded by the -padsize=
option. It remains, however, as a shorthand for -padsize=15s.
If the -pad option refers to an audio track, cdrecord pads the
audio data to be a multiple of 2352 bytes. The audio data pad‐
ding is done with binary zeroes which is equal to absolute
silence.
The -pad option remains valid until disabled by -nopad. Does
not pad the following tracks. This is the default. Sets the
amount of data to be appended as padding to the next track to #.
Opposed to the behavior of the -pad option, the value for -pad‐
size= is reset to zero for each new track. See the -fs= option
for possible arguments. Use this option if your CD-drive is not
able to read the last sectors of a track or if you want to be
able to read the CD on a Linux system with the ISO-9660 filesys‐
tem read-ahead bug. If an empty file is used for track data,
this option may be used to create a disk that is entirely made
of padding. If this flag is present, all TOC entries for subse‐
quent audio tracks indicate that the audio data has been sampled
with 50/15 μsec preemphasis. The data, however is not modified
during the process of transferring from file to disk. This
option has no affect on data tracks. If this flag is present,
all TOC entries for subsequent audio tracks indicates that the
audio data has been mastered with linear data. This is the
default. Sets the pregap size for the next track. This option
currently only makes sense with the TEAC drive when creating
track-at-once disks without the 2 second silence before each
track. This option may go away in future. Allows all subsequent
tracks to violate the Read Book track-length standard, which
requires a minimum track length of 4 seconds. This option is
only useful when used in DAO mode. Not all drives support this
feature. The drive must accept the resulting CUE sheet.
Enforces to the Red Book track length standard. Tracks must be
at least 4 seconds. If this flag is present, audio data is
assumed to be in byte-swapped (little-endian) order. Some types
of CD-Writers, for example, Yamaha, Sony and the SCSI-3/mmc
drives require audio data to be presented in little-endian
order, while other writers require audio data to be presented in
the big-endian (network) byte order normally used by the SCSI
protocol. The cdrecord command knows if a CD-Recorder needs
audio data in big- or little-endian order, and corrects the byte
order of the data stream to match the needs of the recorder. You
only need the swab flag if your data stream is in Intel (little-
endian) byte order.
Note that the verbose output of cdrecord shows you if swapping
is necessary to make the byte order of the input data fit the
required byte order of the recorder. The cdrecord command does
not show you if the swab flag was actually present for a track.
If the master image for the next track has been stored on a raw
disk, use this option to specify the valid amount of data on
this disk. If the image of the next track is stored in a regular
file, the size of that file is taken to determine the length of
this track.
If the track contains an ISO 9660 filesystem image use the -iso‐
size option to determine the length of that filesystem image.
In disk-at-once mode and with some drives that use the TEAC pro‐
gramming interface, even in track-at-once mode, cdrecord needs
to know the size of each track before starting to write the
disk. The cdrecord command now checks this and aborts before
starting to write. If this happens you need to run mkisofs
-print-size and use the output as an argument to the -tsize=
option of cdrecord. See the -fs= option for possible arguments.
If this flag is present, all subsequent tracks are written in
CD-ROM XA mode 1 format. The data is a multiple of 2048 bytes.
If this flag is present, all subsequent tracks are written in
CD-ROM XA mode 2 format. The data is a multiple of 2048 bytes.
DESCRIPTION
The cdrecord command is used to record data or audio compact discs on
an Orange Book CD-Recorder.
The device refers to scsibus/target/lun of the CD-Recorder. Operating
systems use a library simulation of the SCSI general driver. Possible
syntax is: -dev= scsibus,target,lun or -dev= target,lun. In the latter
case, the CD-Recorder has to be connected to the default SCSI bus of
the machine. The parameters scsibus, target and lun are integer num‐
bers. Some operating systems or SCSI transport implementations may
require to specify a filename in addition. In this case the correct
syntax for the device is: -dev= devicename:scsibus,target,lun or -dev=
devicename:target,lun. If the name of the device node that has been
specified on such a system refers to exactly one SCSI device, a short‐
hand in the form -dev= devicename:@ or -dev= devicename:@,lun may be
used.
To access remote SCSI devices, prepend the SCSI device name by a
remote-device indicator. The remote device indicator is either
-REMOTE:user@host: or -REMOTE:host: A valid remote SCSI device name may
be -REMOTE:user@host: to allow remote SCSI bus scanning or
-REMOTE:user@host:1,0,0 to access the SCSI device at host connected to
SCSI bus # 1,target 0, lun 0.
To make cdrecord portable to all UNIX platforms, the syntax -dev= devi‐
cename:scsibus,target,lun is preferred as it hides operating-system
specific knowledge about device names from the user. A specific operat‐
ing system must not necessarily support a way to specify a real device
file name nor a way to specify scsibus,target,lun.
The default SCSI bus on the machine is scsibus 0. Watch the boot mes‐
sages or look at-/var/adm/messages for more information about the SCSI
configuration of your machine. If you have problems figuring out what
values for scsibus,target,lun should be used, try the -scanbus option
of cdrecord.
If a file /etc/default/cdrecord exists, the parameter to the -dev=
option may also be a drive name label in said file (see FILES section).
On SVr4 compliant systems, cdrecord uses the real time class to get the
highest scheduling priority that is possible (higher than all kernel
processes). On systems with POSIX realtime scheduling, cdrecord also
uses real time scheduling but may not be able to gain a priority that
is higher than all kernel processes.
In track-at-once mode, each track corresponds to a single file that
contains the prepared data for that track. If the argument is -, stan‐
dard input is used for that track. Only one track may be taken from
stdin.
EXAMPLES
For all examples below, it is be assumed that the CD-Recorder is con‐
nected to the primary SCSI bus of the machine. The SCSI target id is
set to 2.
To record a pure CD-ROM at double speed using data from the file cdim‐
age.raw: # cdrecord-v speed=2 dev=2,4,0 cdimage.raw
To create an image for a ISO 9660 filesystem with Rock Ridge exten‐
sions: # mkisofs -R -o cdimage.raw /home/joerg/master/tree
To check the resulting file before writing to CD on Linux: # mount
cdimage.raw -r -t iso9660 -o loop /mnt # ls -lR /mnt umount /mnt #
umount /mnt
If the overall speed of the system is sufficient and the structure of
the filesystem is not too complex, cdrecord runs without creating an
image of the ISO 9660 filesystem. Simply run the pipeline: # mkisofs -R
/master/tree | cdrecord-v fs=6m speed=2 dev=2,4,0 -
The recommended minimum fifo size for running this pipeline is 4
MBytes. As the default fifo size is 4 MB, the -fs= option needs only
be present if you want to use a different fifo size. If your system is
loaded, you should run mkisofs in the real-time class. To raise the
priority of mkisofs replace the command # mkisofs -R /master/tree
To record a pure CD-DA (audio) at single speed with each track con‐
tained in a file named track01.cdaudio, track02.cdaudio, etc: #
cdrecord-v speed=1 dev=2,4,0 -audio track*.cdaudio
To check if you can use double speed for the example above, use the
dummy write option: # cdrecord-v-dummy speed=2 dev=2,4,0 -audio
track*.cdaudio
To handle drives that need to know the size of a track before starting
to write, first run # mkisofs -R -q -print-size /master/tree
and then run # mkisofs -R /master/tree | cdrecord speed=2 dev=2,4,0
tsize=XXXs -
where XXX is replaced by the output of the previous run of mkisofs.
To copy an audio CD in the most accurate way, first run # cdda2wav
-v255 -D2,4,0 -B -Owav
and then run # cdrecord-v dev=2,4,0 -dao -useinfo *.wav
ENVIRONMENT
This may either hold a device identifier that is suitable to the open
call of the SCSI transport library or a label in the file
/etc/default/cdrecord. Sets the default size of the fifo (see also the
-fs= option). Sets the default speed value for writing (see also the
-speed option).
FILES
Default values can be set for the following options in
/etc/default/cdrecord. This may either hold a device identifier that
is suitable to the open call of the SCSI transport library or a label
in the file /etc/default/cdrecord that it allows to identify a specific
drive on the system. Sets the default speed value for writing (see
also the -speed option). For example, CDR_SPEED=2. Sets the default
size of the fifo (see also the -fs= #option). For example, CDR_FIFOS‐
IZE=8m. is an identifier for a specific drive on the system. Such an
identifier may not contain the four characters comma (,), slash (/), at
(@), or colon (:).
Each line that follows a label contains a TAB-separated list of
items. Currently, three items are recognized: the SCSI ID of
the drive, the default speed that should be used for this drive
and the default fifo size that should be used for this drive.
The values for -speed and -fifosize may be set to -1 to tell
cdrecord to use the global defaults. A typical line may look
this way: # teac1= 0,5,0 4 8m # yamaha= 1,6,0 -1 -1
This tells cdrecord that a drive named teac1 is at scsibus 0,
target 5, lun 0 and should be used with -speed=4 and a -fs=8 MB.
A second drive may be found at scsibus 1, target 6, lun 0 and
uses the default speed and the default fifo size.
NOTES
Disks made in track-at-once mode are not suitable as masters for direct
mass production by CD manufacturers. You need the disk-at-once option
to record such disks. Nevertheless the disks made in track-at-once mode
normally are read in all CD players. Some old audio CD players however
may produce a two second click between two audio tracks.
The minimal size of a track is 4 seconds or 300 sectors. If you write
smaller tracks, the CD-Recorder adds dummy blocks. This is not an
error, even though the SCSI-error message looks this way.
The cdrecord command has been tested on an upgraded Philips CDD-521
recorder at single and double speed on a SparcStation 20/502 with no
problems; slower computer systems should work also. The newer
Philips/HP/Plasmon/Grundig drives as well as Yamaha CDR-100 and CDR-102
work also. The Plasmon RF-4100 works but has not been tested in multi‐
session. A Philips CDD-521 that has not been upgraded does not work.
The Sony CDU-924 has been tested, but does not support XA-mode2 in
hardware. The Sony therefore cannot create conforming multisession
disks. The Ricoh RO-1420C works, but some people seem to have problems
using them with -speed=2; try -speed=0 in this case.
The Yamaha CDR-400 and all new SCSI-3/mmc conforming drives are sup‐
ported in single and multisession.
You should run several tests in all supported speeds of your drive with
the -dummy option turned on if you are using cdrecord on an unknown
system. Writing a CD is a realtime process. NFS does not always deliver
constantly the needed data rates. If you want to use cdrecord with CD-
images that are located on an NFS mounted filesystem, be sure that the
fifo size is big enough. It is recommended that you leave the system as
lightly loaded as possible while writing a CD. If you want to make sure
that buffer underruns are not caused by your source disk, use the com‐
mand:
# cdrecord-dummy dev=2,4,0 padsize=600m /dev/null
to create a disk that is entirely made of dummy data. The cdrecord com‐
mand needs to run as root to get access to the /dev/scg? device nodes
and to be able to lock itself into memory.
If you do not want to allow users to become root on your system,
cdrecord may safely be installed suid root. This allows all users or a
group of users with no root privileges to use cdrecord. The cdrecord
command in this case checks to determine if the real user would have
been able to read the specified files. To give all user access to use
cdrecord, enter: # chown root /usr/local/bin/cdrecord # chmod 4711
/usr/local/bin/cdrecord
To give a restricted group of users access to cdrecord, enter: # chown
root /usr/local/bin/cdrecord # chgrp cdburners /usr/local/bin/cdrecord
# chmod 4710 /usr/local/bin/cdrecord
and add a group cdburners on your system.
Never give write permissions for the /dev/scg? devices to nonroot
users unless you would allow anybody to read/write/format all your
disks.
Do not connect old drives that do not support disconnect/reconnect to
either the SCSI bus that is connected to the CD-Recorder or the source
disk.
A compact disc can have no more than 99 tracks.
When creating a disc with both audio and data tracks, the data should
be on track 1 otherwise you should create a CDplus disk which is a mul‐
tisession disk with the first session containing the audio tracks and
the following session containing the data track.
Many operating systems are not able to read more than a single data
track or need special software to do so.
More information on the SCSI command set of a HP CD-Recorder can be
found at:
http://www.hp.com/isgsupport/cdr/index.html
If you have more information or SCSI command manuals for currently
unsupported CD-Recorders please contact the author.
The Philips CDD 521 CD-Recorder (even in the upgraded version) has sev‐
eral firmware bugs. Some of them force you to power cycle the device or
to reboot the machine.
When using cdrecord with the broken Linux SCSI generic (sg) driver. You
should note that cdrecord uses a hack that tries to emulate the func‐
tionality of the sg driver. Unfortunately, the sg driver on Linux has
several severe bugs: It cannot see if a SCSI command could not be sent
at all. It cannot get the SCSI status byte. The cdrecord command for
that reason cannot report failing SCSI commands in some situations. It
cannot get a real DMA count of transfer. The cdrecord command cannot
tell you if there is an DMA residual count. It cannot get the number
of bytes valid in auto sense data. The cdrecord command cannot tell
you if device transfers no sense data at all. It fetches too little
data in auto request sense (CCS/SCSI-2/SCSI-3 needs >= 18).
The fifo percent output is computed just after a block of data has been
written to the CD-Recorder. For this reason, there is never 100% fifo
fill while the fifo is in streaming mode.
DIAGNOSTICS
You have 9 seconds to type ^C to abort cdrecord after you see the mes‐
sage: Starting to write CD at speed %d in %s mode for %s session.
A typical error message for a SCSI command looks like the following:
cdrecord: I/O error. test unit ready: scsi sendcmd: no error CDB: 00
20 00 00 00 00 status: 0x2 (CHECK CONDITION) Sense Bytes: 70 00 05 00
00 00 00 0A 00 00 00 00 25 00 00 00 00 00 Sense Key: 0x5 Illegal
Request, Segment 0 Sense Code: 0x25 Qual 0x00 (logical unit not sup‐
ported) Fru 0x0 Sense flags: Blk 0 (not valid) cmd finished after
0.002s timeout 40s
The first line gives information about the transport of the command.
The text after the first colon gives the error text for the system call
from the view of the kernel. It usually is I/O error unless other prob‐
lems happen. The next words contain a short description for the SCSI
command that fails. The rest of the line tells you if there were any
problems for the transport of the command over the SCSI bus. The output
fatal error means that it was not possible to transport the command
(that is, no device is present at the requested SCSI address).
The second line prints the SCSI command descriptor block for the failed
command.
The third line gives information on the SCSI status code returned by
the command if the transport of the command succeeds. This is error
information from the SCSI device.
The fourth line is a hexadecimal dump of the auto-request sense infor‐
mation for the command.
The fifth line is the error text for the sense key if available, fol‐
lowed by the segment number that is only valid if the command was a
copy command. If the error message is not directly related to the cur‐
rent command, the text deferred error is appended.
The sixth line is the error text for the sense code and the sense qual‐
ifier, if available. If the type of the device is known, the sense data
is decoded from tables in scsierrs.c. The text is followed by the error
value for a field-replaceable unit.
The seventh line prints the block number that is related to the failed
command and text for several error flags. The block number may not be
valid.
The eighth line reports the timeout set up for this command and the
time that the command really needed to be finished.
The following message is not an error: Track 01: Total bytes read/writ‐
ten: 2048/2048 (1 sectors). cdrecord: I/O error. flush cache: scsi
sendcmd: no error CDB: 35 00 00 00 00 00 00 00 00 00 status: 0x2
(CHECK CONDITION) Sense Bytes: F0 00 05 80 00 00 27 0A 00 00 00 00 B5
00 00 00 00 00 Sense Key: 0x5 Illegal Request, Segment 0 Sense Code:
0xB5 Qual 0x00 (dummy data blocks added) Fru 0x0 Sense flags: Blk
-2147483609 (valid) cmd finished after 0.002s timeout 40s
It simply notifies that a track that is smaller than the minimum size
has been expanded to 300 sectors.
RESTRICTIONS
The cdrecord currently only warns if the input data does not fit on the
disk. If you do not abort the command you get unpredictable results.
AUTHOR
This page has been adapted from information provided by:
Joerg Schilling
Seestr. 110 D-13353
Berlin Germany
Additional information can be found at
http://www.fokus.gmd.de/research/cc/glone/employ‐
ees/jeorg.schilling/private/cdrecord.html
SEE ALSO
Commands: mkisofs(8)cdrecord(1)