Sends a SCSI WRITE BUFFER command to DEVICE, along with data provided
by the user. In some cases no data is required, or data can be read from the
file given in the --in=FILE option, or data is read from stdin when
either --raw or --in=- is given.
Some WRITE BUFFER command variants do not have associated data to send to the
device, for example "activate_mc" ("activate deferred microcode").
Arguments to long options are mandatory for short options as well.
output the usage message then exit. If used multiple times also prints
the mode names and their acronyms.
this option sets the buffer id field in the cdb. ID is a value between
0 (default) and 255 inclusive.
read data from file FILE that will be sent with the WRITE BUFFER
command. If FILE is '-' then stdin is read until an EOF is
detected (this is the same action as --raw).
where LEN is the length, in bytes, of data to be written to the device.
If not given (and length cannot be deduced from --in=FILE or
--raw) then defaults to zero. If the option is given and the length
deduced from --in=FILE or --raw is less (or no data is
provided), then bytes of 0xff are used as fill bytes.
this option sets the mode field in the cdb. MO is a value between
0 (default) and 31 inclusive. Alternatively an abbreviation can be given.
To list the available mode abbreviations give an invalid
one (e.g. '--mode=xxx') or use the '-hh' option.
this option sets the buffer offset field in the cdb. OFF is a value
between 0 (default) and 2**24-1 . It is a byte offset.
read data from stdin until an EOF is detected. This data is sent with
the WRITE BUFFER command to DEVICE. The action of this option is the
same as using '--in=-'.
this option is only active when --in=FILE is given and
FILE is a regular file, rather than stdin. Data is read
starting at byte offset SKIP to the end of file (or the amount
given by --length=LEN). If not given the byte offset defaults to
0 (i.e. the start of the file).
increase the level of verbosity, (i.e. debug output).
print the version string and then exit.
If no --length=LEN is given this utility reads up to 8 MiB of data
from the given file FILE (or stdin). If a larger amount of data is
required then the --length=LEN option should be given. The user
should be aware that most operating systems have limits on the amount
of data that can be sent with one SCSI command. In Linux this
depends on the pass through mechanism used (e.g. block SG_IO or
the sg driver) and various setting in sysfs in the linux lk 2.6
series (e.g. /sys/block/sda/queue/max_sectors_kb).
Downloading incorrect microcode into a device has the ability to render
that device inoperable. One would hope that the device vendor verifies
the data before activating it. If the SCSI WRITE BUFFER command is given
values in its cdb (e.g. LEN) that are inappropriate (e.g. too large)
then the device should respond with a sense key of ILLEGAL REQUEST and
an additional sense code of INVALID FIELD in CDB. If a WRITE BUFFER
command (or a sequence of them) fails due to device vendor verification
checks then it should respond with a sense key of ILLEGAL REQUEST and
an additional sense code of COMMAND SEQUENCE ERROR.
All numbers given with options are assumed to be decimal.
Alternatively numerical values can be given in hexadecimal preceded by
either "0x" or "0X" (or has a trailing "h" or "H").
The exit status of sg_write_buffer is 0 when it is successful. Otherwise
see the sg3_utils(8) man page.