cdrw - CD read and write
cdrw -i [-vSCO] [-d device] [-p speed] [image-file]
cdrw -a [-vSCO] [-d device] [-p speed] [-T audio-type]
cdrw -x [-v] [-d device] [-T audio-type] track-number out-
cdrw -c [-vSC] [-d device] [-p speed] [-m tmp-dir] [-s src-
cdrw -b [-v] [-d device] all | session
cdrw -M [-v] [-d device]
cdrw -l [-v]
The cdrw command provides the ability to create data and
audio CDs. It also provides the ability to extract audio
tracks from an audio CD. Any MMC-compliant CD-R or CD-RW
drive can be used with cdrw.
cdrw will search for a CD writer device connected to the
system, unless the user specifies a device with the -d
option. If it finds a single such writer device, it will use
that as the default CD writer device for the command.
When more than one CD writer is connected to the system, use
the -d option to indicate which device is desired. The dev-
ice name can be specified in one of the following ways:
/dev/rdsk/cNtNdNsN, cNtNdNsN, cNtNdN, or a symbolic name
used by volume manager, such as cdrom or cdrom1. The -l
option will provide a list of CD writers.
For instructions on adding a USB-mass-storage-class-
compliant CD-RW to your system, see scsa2usb(7D).
Creating Data CDs
When creating data CDs, cdrw uses the track-at-once mode of
writing. With the -i option, the user will specify a file
that contains the data to write on CD media. In the absence
of such a file, cdrw will read data from standard input.
In either case, the data will typically first have been
prepared by using the mkisofs(1M) command to convert the
file and file information into the High Sierra format used
on CDs. See the examples that include use of this command.
Creating Audio CDs
For creating an audio CD, using the -a option, single or
multiple audio files can be specified. All of the audio
files should be in the supported audio formats. Currently
approved formats are:
sun Sun .au files with data in Red Book CDDA form
wav RIFF (.wav) files with data in Red Book CDDA form
cda .cda files having raw CD audio data (that is, 16
bit PCM stereo at 44.1 KHz sample rate in
aur .aur files having raw CD data in big-endian
If no audio format is specified, cdrw tries to understand
the audio file format based on the file extension. The case
of the characters in the extension is ignored. If a format
is specified using the -T option, it will be assumed as the
audio file type for all the files specified. Also, -cdrw
will close the session after writing the audio tracks.
Therefore, the tracks to be written should be specified in a
single command line.
cdrw can also be used for extracting audio data from an
audio CD with the -x option. The CD should have tracks in
Red Book CDDA form. By default, the output format is based
on the file extension. A user can specify a sun, wav, cda,
or aur output format using the -T option.
cdrw can be used to copy single session data CD-ROMs and Red
Book audio CDs. For copying a CD, cdrw looks for a specified
source device. If no source device is specified when using
the -c option, the current CD writing device is assumed to
be the source. cdrw will extract the track or tracks into a
temporary file and will look for a blank writable CD-R/RW
media in the current CD writing device. If no such media is
found, the user will be asked to insert a blank writable CD
media in the current CD writing device. If enough space is
not available in the default temporary directory, an alter-
native directory can be specified using the -m option.
Erasing CD-RW Media
Users have to erase the CD-RW media before it can be re-
written. With the -b option, the following flavors of eras-
ing are currently supported:
Erase the last session.
all Erase the entire media.
If the session erasing type is used, cdrw will erase the
last session. If there is only one session recorded on the
CD-RW (for example, a data/audio CD-RW created by this
tool), then session erasing is useful as it will only erase
the portion that is recorded, leaving behind a blank disk.
This is faster than erasing the entire media.
The all erasing type should be used if it is a multisession
disk, or the last session is not closed, or disk status is
unknown, and the user wishes to erase the disk. With this
type of erase, cdrw will erase the entire disk.
Checking device-list or media-status
The user can get a list of CD writing devices currently
present in the system with the -l option. Also, for a par-
ticular media, the user can get the blanking status and
table of contents through the -M option. The -M option also
prints information about the last session start address and
the next writable address. This information, along with the
-O option, can be used to create multisession CDs. Please
refer to mkisofs(1M) for more information.
The following options are supported:
-a Creates an audio disk. At least one audio-file name
must be specified. A CD can not have more than 99
audio tracks, so no more than 99 audio files can be
specified. Also, the maximum audio data that can be
written to the media by default is 74 minutes, unless
-C is specified.
-b Blanks a CD-RW media. The type of erasing must be
specified by the all or session argument.
-c Copies a CD. If no other argument is specified, the
default CD writing device is assumed to be the source
device as well. In this case, the copying operation
will read the source media into a temporary directory
and will prompt the user to place a blank media into
the drive for copying to proceed.
-C Uses media stated capacity. Without this option, cdrw
will use a default value for writable CD media, which
is 74 minutes for an audio CD or 681984000 bytes for a
-d Specifies CD writing device.
-h Help. Prints usage message.
-i Specifies image file for creating data CDs. The file
size should be less than what can be written on a CD-R
or CD-RW media, which is 681984000 bytes by default or
the media stated capacity if the -C option is used.
Also, it is better to have the file locally available
instead of having it on an NFS-mounted filesystem,
because the CD writing process expects data to be
available continuously without interruptions.
-l Lists all the CD writers found in the system.
-m Uses an alternate temporary directory instead of sys-
tem default temporary directory for storing track data
while copying a CD. An alternate temporary directory
might be required because the amount of data on a CD
can be huge (as much as 800 Mbytes for an 80 minute
audio CD) and the system default temporary directory
might not have that much space.
-M Reports media status. cdrw will report if the media is
blank or not, its table of contents, the last
session's start address, and the next writable address
if the disk is open.
-O Keeps the disk open. cdrw will close the session, but
it will keep the disk open so that another session can
be added later on to create a multisession disk.
-p Sets the CD writing speed. For example, -p 4 will set
the speed to 4X. If this option is not specified, cdrw
will use the default speed of the CD writer. If this
option is specified, cdrw will try to set the drive
write speed to this value, but there is no guarantee
of the speed actually used by the drive.
-s Specifies source device for copying CD.
-S Simulation mode. In this mode, cdrw will do everything
with the drive laser turned off, so nothing will be
written to the media. This can be used to verify if
the system can provide data at a rate good enough for
-T Audio format to use extracting audio files or reading
audio files for audio CD creation. The audio-type can
be sun, wav, cda, or aur.
-v Verbose mode.
-x Extracts audio data from an audio track.
Example 1: Creating a data CD
example% cdrw -i /local/iso_image
Example 2: Creating a CD from a directory
This example creates a CD from the directory tree /home/foo:
example% mkisofs -r /home/foo 2>/dev/null | cdrw -i -p 1
Example 3: Extracting an audio track number
This example extracts audio track number 1 to
example% cdrw -x -T wav 1 /home/foo/song1.wav
Example 4: Using wav files
This example creates an audio CD from wav files on disk:
example% cdrw -a song1.wav song2.wav song3.wav song4.wav
Example 5: Erasing a CD-RW media
This example erases a CD-RW media in a CD-RW drive:
example% cdrw -b all
Example 6: Creating a data CD with multiple drives
This example creates a data CD on a system with multiple
example% cdrw -d c1t6d0s2 -i /home/foo/iso-image
Example 7: Checking data delivery rate
This example checks if the system can provide data to a CD-
RW drive at a rate sufficient for the write operation:
example% cdrw -S -i /home/foo/iso-image
Example 8: Running at a higher priority
This example runs cdrw at a higher priority (for root user
example# priocntl -e -p 60 cdrw -i /home/foo/iso-image
Example 9: Creating a multi-session disk
Create the first session image using mkisofs(1M) and record
it onto the disk without closing the disk:
example% cdrw -O -i /home/foo/iso-image
Additional sessions can be added to an open disk by creating
an image with mkisofs(1M) using the session start and next
writable address reported by cdrw.
example% cdrw -M
Track No. |Type |Start address
1 |Data | 0
Leadout |Data | 166564
Last session start address: 162140
Next writable address: 173464
example% mkisofs -o /tmp/image2 -r -C 0,173464 -M \
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| Availability | SUNWcdrw |
audioconvert(1), mkisofs(1M), priocntl(1), attributes(5),
rbac(5), scsa2usb(7D), sd(7D)
The CD writing process requires data to be supplied at a
constant rate to the drive. It is advised to keep I/O
activity to a minimum and shut down the related applications
while writing CDs.
When making copies or extracting audio tracks, it is better
to use an MMC compliant source CD-ROM drive. The CD writing
device can be used for this purpose.
Before writing a CD, ensure that the media is blank by using
the -M option and use the -S simulation mode to test the
system to make sure it can provide data at the required
rate. In case the system is not able to provide data at the
required rate, try simulation with a slower write speed set
through the -p option. Users can also try to run cdrw at a
higher priority using the priocntl(1) command.
The -p option is provided for users who are aware of the
CD-R/RW drive and its capabilities to operate at different
write speeds. Some commercially available drives handle the
drive speed setting command differently, so use this option
Most commercially available drives allow writing beyond 74
minutes as long as the media has the capacity (such as 80-
minute media). However, such capability of writing beyond 74
minutes might not be supported by the drive in use. If the
drive being used supports such capability, then use the -C
option to indicate that the tool should rely on the capacity
indicated by the media.
The cdrw command uses rbac(5) to control user access to the
devices. By default, cdrw is accessible to all users but can
be restricted to individual users. Please refer to "Adminis-
tering CD-R/CD-RW devices" in the System Administration
Guide: Basic Administration for more information.
Man(1) output converted with