sg_opcodes(8) - phpMan

SG_OPCODES(8) SG3_UTILS SG_OPCODES(8)

NAME
sg_opcodes - report supported SCSI commands or task management functions

SYNOPSIS
sg_opcodes [--alpha] [--help] [--hex] [--no-inquiry] [--opcode=OP] [--raw] [--rctd]
[--repd] [--sa=SA] [--tmf] [--unsorted] [--verbose] [--version] DEVICE

sg_opcodes [-a] [-n] [-o=OP] [-q] [-R] [-s=SA] [-t] [-u] [-v] [-V] [-?] DEVICE

DESCRIPTION
This utility sends a SCSI REPORT SUPPORTED OPERATION CODES or a REPORT SUPPORTED TASK MAN-
AGEMENT FUNCTIONS command to the DEVICE and then outputs the response. The default action
is to report supported operation codes. In this mode it will either list all supported
commands or give detailed information on a specific command identified by the --opcode=OP
option (perhaps with additional information from the --sa=SA option).

The name of a SCSI command depends on its peripheral device type (e.g. a disk). The REPORT
SUPPORTED OPERATION CODES and REPORT SUPPORTED TASK MANAGEMENT FUNCTIONS commands are not
supported in the MMC command set for CD and DVD devices. This utility does an INQUIRY to
obtain the peripheral device type and prints out the vendor, product and revision strings.

A similar facility to query supported operation codes previously was available via the
CmdDt bit in the SCSI INQUIRY command (see sg_inq(8)). However that facility was made
obsolete and replaced by the REPORT SUPPORTED OPERATION CODES command in SPC-3 (revision
4) during February 2002.

This utility supports two command line syntaxes, the preferred one is shown first in the
synopsis and explained in this section. A later section on the old command line syntax
outlines the second group of options.

OPTIONS
Arguments to long options are mandatory for short options as well.

-a, --alpha
when all supported commands are being listed there is no requirement for the device
server (i.e. the DEVICE) to sort the list of commands. When this option is given
the list of supported commands is sorted by name (alphabetically). When this option
and the --unsorted option are both _not_ given then the list of supported commands
is sorted numerically (first by operation code and then by service action).

-h, --help
outputs the usage message summarizing command line options then exits. Ignores
DEVICE if given.

-H, --hex
outputs the response in ASCII hexadecimal to stdout.

-n, --no-inquiry
Prior to calling a SCSI REPORT SUPPORTED OPERATION CODES or a REPORT SUPPORTED TASK
MANAGEMENT FUNCTIONS command, a SCSI INQUIRY command is performed. The reason is to
determine the peripheral device type (pdt) of the DEVICE as this is helpful in
translating operation codes to the command names. By default this utility prints a
summary of INQUIRY command response on stdout. If this option (or the --raw option)
is given then that summary is not printed on stdout.

-O, --old
Switch to older style options. Please use as first option.

-o, --opcode=OP
the DEVICE will be queried for the given operation code ( i.e. the OP value) which
is the first byte of a SCSI command. OP is decimal unless prefixed by "0x" or it
has a trailing "h". OP should be in the range 0 to 255 (0xff) inclusive. When this
option is not given then all available SCSI commands supported by the DEVICE are
listed.

-r, --raw
output the response in binary to stdout. Error messages and warnings, if any, are
sent to stderr.

-R, --rctd
set report command timeout descriptor (RCTD) bit in the cdb. The response may or
may not contain command timeout descriptors. If available they are output. If sup-
ported there are two values: a nominal command timeout and a recommended command
timeout. Both have units of seconds. A value of zero means that no timeout is indi-
cated and this is shown in the corresponding decoded output as "-".

-q, --repd
set read extended parameter data (REPD) bit in the report task management functions
cdb. 16 bytes rather than the default 4 bytes expected in the response. This was
added in SPC-4 (revision 26).

-s, --sa=SA
the DEVICE will be queried for a command with the given service action (i.e. the SA
value). Used in conjunction with the --opcode=OP option. If this option is not
given, --opcode=OP is given and the command in question does have a service action
then a value of 0 will be assumed. SA is decimal and expected to be in the range 0
to 65535 (0xffff) inclusive.

-t, --tmf
list supported task management functions. This is done with the SCSI REPORT SUP-
PORTED TASK MANAGEMENT FUNCTIONS command. When this option is chosen the --alpha,
--opcode=OP, --rctd, --sa=SA and --unsorted options are ignored.

-u, --unsorted
when all supported commands are being listed there is no requirement for the device
server (i.e. the DEVICE) to sort the list of commands. When this option is given
the list of supported commands is in the order given by the DEVICE. When this
option is not given the supported commands are sorted numerically (first by opera-
tion code and then by service action).

-v, --verbose
increase level of verbosity. Can be used multiple times.

-V, --version
print out version string then exit.

NOTES
As of SPC-4 revision 7a the recognized task management functions are: abort set, abort
task set, clear ACA, clear task set, I_T nexus reset, logical unit reset, query task, tar-
get reset and wakeup. As of SPC-4 revision 26 target reset and wakeup have been made
obsolete while query task set and query asynchronous event notification have been added.

In the 2.4 series of Linux kernels the DEVICE must be a SCSI generic (sg) device. In the
2.6 series block devices (e.g. SCSI disks and DVD drives) can also be specified. For exam-
ple "sg_opcodes /dev/sda" will work in the 2.6 series kernels.

EXIT STATUS
The exit status of sg_opcodes is 0 when it is successful. Otherwise see the sg3_utils(8)
man page.

OLDER COMMAND LINE OPTIONS
The options in this section were the only ones available prior to sg3_utils version 1.23 .
In sg3_utils version 1.23 and later these older options can be selected by either setting
the SG3_UTILS_OLD_OPTS environment variable or using '--old' (or '-O) as the first option.

-a sort command alphabetically. Equivalent to --alpha in main description.

-n don't print a summary of the SCSI INQUIRY response on stdout.

-N, --new
Switch to the newer style options.

-o=OP the DEVICE will be queried for the given operation code (i.e. OP) which is the
first byte of a SCSI command. OP is hexadecimal and expected to be in the range 0
to ff inclusive. When this option is not given then all available SCSI commands
supported by the DEVICE are listed.

-q set the read extended parameter data (REPD) bit in report TMF cdb. Equivalent to
--repd in main description.

-R set the report command timeout descriptor (RCTD) bit in cdb. Equivalent to --rctd
in main description.

-s=SA the DEVICE will be queried for a command with the given service action (i.e. SA).
Used in conjunction with the -o=OP option. If this option is not given, -o=OP is
given and the command in question does have a service action then a value of 0 will
be assumed. SA is hexadecimal and expected to be in the range 0 to ffff inclusive.

-t list supported task management functions. Equivalent to --tmf in the main descrip-
tion.

-u output all supported commands in the order given by DEVICE. Equivalent to
--unsorted in main description.

-v increase level of verbosity. Can be used multiple times.

-V print out version string then exit.

-? output usage message. Ignore all other parameters.

EXAMPLES
The examples in this page use Linux device names. For suitable device names in other sup-
ported Operating Systems see the sg3_utils(8) man page.

To see the information about a specific command give its operation code to the '--op='
option. A command line invocation is shown first followed by a typical response:

# sg_opcodes --op=93h /dev/sdb

Opcode=0x93
Command_name: Write same(16)
Command supported [conforming to SCSI standard]
Usage data: 93 e2 00 00 00 00 ff ff ff ff 00 00 ff ff 00 00

The next example shows the supported task management functions:

# sg_opcodes --tmf -n /dev/sdb

Task Management Functions supported by device:
Abort task
Abort task set
Clear ACA
Clear task set
Logical unit reset
Query task

AUTHOR
Written by Douglas Gilbert

REPORTING BUGS
Report bugs to <dgilbert at interlog dot com>.

COPYRIGHT
Copyright (C) 2004-2012 Douglas Gilbert
This software is distributed under the GPL version 2. There is NO warranty; not even for
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.