NAME
sg_get_config - sends a SCSI GET CONFIGURATION command (MMC-4 +)
SYNOPSIS
sg_get_config [--brief] [--current] [--help] [--hex] [--inner-hex]
[--list] [--raw] [--rt=RT] [--starting=FC] [--verbose] [--version]
DEVICE
DESCRIPTION
Sends a SCSI GET CONFIGURATION command to DEVICE and decodes the
response. The response includes the features and profiles of the
device. Typically these devices are CD, DVD, HD-DVD and BD players
that may (but not necessarily) have media in them. These devices may
well be connected via ATAPI, USB or IEEE 1394 transports. In such cases
they are "SCSI" devices only in the sense that they use the
"Multi-Media command" set (MMC). MMC is a specialized SCSI command set
whose definition can be found at http://www.t10.org .
This utility is based on the MMC-4 and later draft standards. See
section 5 on "Features and Profile for Multi_Media devices" for more
information on specific feature parameters and profiles. The
manufacturer’s product manual may also be useful.
Since modern DVD and BD writers support many features and profiles, the
decoded output from this utility can be large. There are various ways
to cut down the output. If the --brief option is used only the feature
names are shown and the feature parameters are not decoded.
Alternatively if only one feature is of interest then this combination
of options is appropriate: "--rt=2 --starting=FC". Another possibility
is to show only the features that are relevant to the media in the
drive (i.e. "current") with the "--rt=1" option.
OPTIONS
Arguments to long options are mandatory for short options as well.
-b, --brief
show the feature names but don’t decode the parameters of those
features. When used with --list outputs known feature names but
not known profile names.
-c, --current
output features marked as current. This option is equivalent to
’--rt=1’.
-h, --help
output the usage message then exit.
-H, --hex
output the response in hex (don’t decode response).
-i, --inner-hex
decode to the feature name level then output each feature’s data
in hex.
-l, --list
list all known feature and profile names. Ignore the device name
(if given). Simply lists the feature names and profiles
(followed by their hex values) that this utility knows about. If
--brief is also given then only feature names are listed.
-r, --rt=RT
where RT is the field of that name in the GET CONFIGURATION cdb.
Allowable values are 0, 1, 2, or 3 . The command’s action also
depends on the value given to the --starting=FC option. The
default value is 0. When RT is 0 then all features, regardless
of currency, are returned (whose feature code is greater than or
equal to FC given to --starting=). When RT is 1 then all current
features are returned (whose feature code is greater than or
equal to FC). When RT is 2 then the feature whose feature code
is equal to FC, if any, is returned. When RT is 3 the response
is reserved (probably yields an "illegal field in cdb" error).
To simplify the meanings of the RT values are:
0 : all features, current on not
1 : only current features
2 : only feature whose code is FC
3 : reserved
-R, --raw
output response in binary (to stdout). Note that the short form
is -R unlike most other utilities in this package that use -r
for this action.
-s, --starting=FC
where FC is the feature code value. This option works closely
with the --rt=RT option. The FC value is in the range 0 to 65535
(0xffff) inclusive. Its default value is 0. A value prefixed
with "0x" (or a trailing ’h’) is interpreted as hexadecimal.
-v, --verbose
increase the level of verbosity, (i.e. debug output).
-V, --version
print the version string and then exit.
NOTES
There are multiple versions of the MMC (draft) standards: MMC [1997],
MMC-2 [2000], MMC-3 [2002], MMC-4 and MMC-5. The first three are now
ANSI INCITS standards with the year they became standards shown in
brackets. The draft immediately prior to standardization can be found
at http://www.t10.org . In the initial MMC standard there was no GET
CONFIGURATION command and the relevant information was obtained from
the "CD capabilities and mechanical status mode page" (mode page 0x2a).
It was later renamed the "MM capabilities and mechanical status mode
page" and has been made obsolete in MMC-4 and MMC-5. The GET
CONFIGURATION command was introduced in MMC-2 and has become a
replacement for that mode page. New features such as support for "BD"
(blue ray) media type can only be found by using the GET CONFIGURATION
command. Hence older CD players may not support the GET CONFIGURATION
command in which case the "MM capabilities ..." mode page can be
checked with sdparm(8), sginfo(8) or sg_modes(8).
In the 2.4 series of Linux kernels the DEVICE must be a SCSI generic
(sg) device. In the 2.6 series block devices can also be specified. For
example "sg_get_config /dev/hdc" will work in the 2.6 series kernels as
long as /dev/hdc is an ATAPI device. In the 2.6 series external DVD
writers attached via USB could be queried with "sg_get_config
/dev/scd1" for example.
EXIT STATUS
The exit status of sg_get_config is 0 when it is successful. Otherwise
see the sg3_utils(8) man page.
AUTHORS
Written by Douglas Gilbert.
REPORTING BUGS
Report bugs to <dgilbert at interlog dot com>.
COPYRIGHT
Copyright © 2004-2008 Douglas Gilbert
This software is distributed under a FreeBSD license. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE.
SEE ALSO
sginfo(8), sg_modes(8), sg_inq(8), sg_prevent(8), sg_start(8) [all in
sg3_utils], sdparm(8)