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man pages section 8: System Administration Commands

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Updated: Thursday, June 13, 2019

sg_read_buffer (8)


sg_read_buffer - send SCSI READ BUFFER command


sg_read_buffer  [--help]  [--hex]  [--id=ID] [--length=LEN] [--mode=MO]
[--offset=OFF] [--raw] [--readonly] [--verbose] [--version] DEVICE


SG_READ_BUFFER(8)                  SG3_UTILS                 SG_READ_BUFFER(8)

       sg_read_buffer - send SCSI READ BUFFER command

       sg_read_buffer  [--help]  [--hex]  [--id=ID] [--length=LEN] [--mode=MO]
       [--offset=OFF] [--raw] [--readonly] [--verbose] [--version] DEVICE

       Sends a SCSI READ BUFFER command to the  DEVICE,  and  if  there  is  a
       response  either  decodes  it,  prints it in hexadecimal or sends it in
       binary to stdout. If a response is received  for  a  "descriptor"  mode
       then,  in  the  absence of --hex and --raw, it is decoded. Response for
       non-descriptor modes are output in hexadecimal unless the --raw  option
       is given.

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

       -h, --help
              output  the usage message then exit. If used multiple times also
              prints the mode names and their acronyms.

       -H, --hex
              output  the  response  in  hexadecimal.  When  given  twice  the
              response  is output in hex with the corresponding representation
              in ASCII to the right of each line.

       -i, --id=ID
              this option sets the buffer id field in the cdb. ID is  a  value
              between 0 (default) and 255 inclusive.

       -l, --length=LEN
              where  LEN is the length, in bytes, that is placed in the "allo-
              cation length" field in the cdb. The default value is 4 (bytes).
              The device may respond with less bytes.

       -m, --mode=MO
              this  option  sets  the  mode  field  in  the cdb. MO is a value
              between 0 (default) and 31 inclusive. Alternatively an abbrevia-
              tion  can  be  given.   See the MODES section below. To list the
              available  mode  abbreviations  use   an   invalid   one   (e.g.
              '--mode=xxx').  As an example, to fetch the read buffer descrip-
              tor give '--mode=desc' .

       -o, --offset=OFF
              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.

       -r, --raw
              if a response is received then it is sent in binary to stdout.

       -R, --readonly
              open the DEVICE read-only (e.g. in Unix with the O_RDONLY flag).
              The default is to open it read-write.

       -v, --verbose
              increase the level of verbosity, (i.e. debug output).

       -V, --version
              print the version string and then exit.

       Following is a list of READ BUFFER command settings for the MODE field.
       First  is an acronym accepted by the MO argument of this utility.  Fol-
       lowing the acronym in square brackets are the corresponding decimal and
       hex  values  that may also be given for MO. The following are listed in
       numerical order.

       hd  [0, 0x0]
              Combined header and data (obsolete in SPC-4).

       vendor  [1, 0x1]
              Vendor specific.

       data  [2, 0x2]

       desc  [3, 0x3]
              Descriptor: yields 4 bytes that contain an offset boundary field
              (1 byte) and buffer capacity (3 bytes).

       echo  [10, 0xa]
              Read data from echo buffer (was called "Echo buffer" in SPC-3).

       echo_desc  [11, 0xb]
              Echo  buffer  descriptor: yields 4 bytes of which the last (low-
              est) 13 bits represent the echo  buffer  capacity.  The  maximum
              echo buffer size is 4096 bytes.

       en_ex  [26, 0x1a]
              Enable  expander  communications  protocol and Echo buffer. Made
              obsolete in SPC-4.

       err_hist  [28, 0x1c]
              Error history. Introduced in SPC-4.

       See attributes(7) for descriptions of the following attributes:

       |Availability   | system/storage/sg3_utils |
       |Stability      | Pass-through uncommitted |
       All numbers given with options are assumed  to  be  decimal.   Alterna-
       tively  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_read_buffer is 0 when it is successful. Otherwise
       see the sg3_utils(8) man page.

       Written by Luben Tuikov and Douglas Gilbert.

       Report bugs to <dgilbert at interlog dot com>.

       Copyright (C) 2006-2014 Luben Tuikov and Douglas Gilbert
       This  software is distributed under a FreeBSD license. There is NO war-
       ranty; not even for MERCHANTABILITY or FITNESS FOR  A  PARTICULAR  PUR-


       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source was downloaded from  http://sg.danny.cz/sg/p/sg3_utils-1.42.tgz

       Further information about this software can be found on the open source
       community website at http://sg.danny.cz/sg/sg3_utils.html.

sg3_utils-1.39                     May 2014                  SG_READ_BUFFER(8)