cdrecord(1)

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cdrecord(1)
NAME
cdrecord - Records audio or data compact discs (CDs) from a master

SYNOPSIS
cdrecord [-general options] [-dev=device]... [-track options] [track1 . . .
trackn]

GENERAL OPTIONS
General options must be entered before any track file name or track option.

-atip 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.

-blank=

type Blanks a CD-RW and exits or blanks a CD-RW before writing. The
blanking type may be one of the following:

all Blanks the entire disk. This may take a long time.

fast Minimally blanks the disk. This results in erasing the PMA,
the TOC and the pregap.

help Displays a list of possible blanking types.

session Blanks the last session.

track Blanks a track.

trtail Blanks the tail of a track.

unclose Uncloses last session.

unreserve
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.

-checkdrive
Checks if a driver for the current drive is present and exits. If
the drive is a known drive, cdrecord uses exit code 0.

-dao Sets disk-at-once mode. This currently only works with MMC drives
that support non-raw Session At Once mode.

-debug=# -d
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.

-defpregap=#
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.

-dev= target
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 different
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
characters ,, /, @ or :, it is interpreted as an label name that
may be found in the file /etc/default/cdrecord. See the FILES
section for more information.

-driver=

name 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 simulation 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.

-driveropts=option list
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.

-dummy 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.

-eject 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.

-fix 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).

-nofix 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.

-force Forces command to continue on some errors. This option currently
implements some tricks that allow you to blank out bad CD-RW disks.

-fs=# 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 memory
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.

-ignsize
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.

-inq Does an inquiry for the drive, prints the inquiry information, and
exits.

-kdebug# -kd=#
Tells the -scg driver to modify the kernel debug value while SCSI
commands are running.

-load Loads the media and exits. This only works with a tray loading
mechanism but seems to be useful when using the Kodak disk
transporter.

-mcn=med_cat_nr
Sets the Media Catalog Number of the CD to med_cat_nr.

-msinfo 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 multisession
information for a disk that is not suitable for this operation.

-multi 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% compatible 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 sectors
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.

-packet Sets packet writing mode. This is an experimental interface.

-pktsize=#
Sets the packet size to #, which forces fixed-packet mode. This is
an experimental interface.

-prcap 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.

-scanbus
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

-silent -s
Does not print out a status report for failed SCSI commands.

-speed=#
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.

-timeout= #
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.

-toc Retrieves and prints out the table of contents or PMA of a CD. With
this option, cdrecord works with CD-R drives and with CD-ROM
drives.

-useinfo
Uses *.inf files to overwrite audio options. If this option is
used, the pregap size information is read from the *.inf file that
is associated with the file that contains the audio data for a
track.

-v Increments the level of general verbosity by one. This displays the
progress of the write process.

-V 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 underrun.

-version
Prints version information and exits.

-waiti 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.

-audio
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 .au or .wav, the file is considered to be a
structured audio data file. The cdrecord command assumes that the file
in this case is a Microsoft .wav file and extracts the audio data from
the files by skipping over the non-audio header information. In all
other cases, cdrecord only works correctly if the audio data stream
does not have any header. Because many structured 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 .wav 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). However, 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 .au or .wav and to -data for all
other files.

-cdi
If this flag is present, all subsequent tracks are written in CDI
format. The data is a multiple of 2048 bytes.

-data
If this flag is present, all subsequent tracks are written in CD-ROM
mode 1 (Yellow Book) format. The data is a multiple 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 .au or .wav and to -data for all
other files.

-index= list
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 following 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.

-isosize
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 -isosize 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.

-isrc=Circumambulate
Sets the International Standard Recording Number for the next track to
Circumambulate.

-mode2
If this flag is present, all subsequent tracks are written in CD-ROM
mode 2 format. The data is a multiple of 2048 bytes.

-pad
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 padding is done with binary zeroes which is equal to
absolute silence.

The -pad option remains valid until disabled by -nopad.

-nopad
Does not pad the following tracks. This is the default.

-padsize=#
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 -padsize=
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 filesystem 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.

-preemp
If this flag is present, all TOC entries for subsequent audio tracks
indicate that the audio data has been sampled with 50/15 usec
preemphasis. The data, however is not modified during the process of
transferring from file to disk. This option has no affect on data
tracks.

-nopreemp
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.

-pregap=#
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.

-shorttrack
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.

-noshorttrack
Enforces to the Red Book track length standard. Tracks must be at least
4 seconds.

-swab
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.

-tsize=#
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 -isosize
option to determine the length of that filesystem image. In disk-at-
once mode and with some drives that use the TEAC programming 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.

-xa1
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.

-xa2
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 numbers. 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 shorthand 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=
devicename:scsibus,target,lun is preferred as it hides operating-system
specific knowledge about device names from the user. A specific operating
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 messages
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 -, standard
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 connected
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
cdimage.raw:

# cdrecord -v speed=2 dev=2,4,0 cdimage.raw

To create an image for a ISO 9660 filesystem with Rock Ridge extensions:

# 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 contained 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
CDR_DEVICE
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.

CDR_FIFOSIZE
Sets the default size of the fifo (see also the -fs= option).

CDR_SPEED
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.

CDR_DEVICE
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.

CDR_SPEED
Sets the default speed value for writing (see also the -speed
option). For example, CDR_SPEED=2.

CDR_FIFOSIZE
Sets the default size of the fifo (see also the -fs= #option). For
example, CDR_FIFOSIZE=8m.

Any other label
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
multisession. 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 supported
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 command:

# cdrecord -dummy dev=2,4,0 padsize=600m /dev/null

to create a disk that is entirely made of dummy data. The cdrecord command
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 multisession
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 several
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
functionality 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 message:

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 supported) 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 problems
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 information
for the command.

The fifth line is the error text for the sense key if available, followed
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 current command, the
text deferred error is appended.

The sixth line is the error text for the sense code and the sense
qualifier, 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/written: 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/employees/jeorg.schilling/private/cdrecord.html

cdrecord(1)

NAME

SYNOPSIS

GENERAL OPTIONS

TRACK OPTIONS

DESCRIPTION

EXAMPLES

ENVIRONMENT

FILES

NOTES

DIAGNOSTICS

RESTRICTIONS

AUTHOR

SEE ALSO