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       sg_read_buffer -	send SCSI READ BUFFER command

       sg_read_buffer  [--help]	 [--hex] [--id=ID] [--inhex=FN]	[--length=LEN]
       [--mode=MO] [--offset=OFF] [--raw] [--readonly] [--specific=MS] [--ver-
       bose] [--version] DEVICE

       Sends  a	 SCSI READ BUFFER command to the DEVICE, and if	there is a re-
       sponse either decodes it, prints	it in hexadecimal or sends it  in  bi-
       nary 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-de-
       scriptor	 modes	are  output  in	hexadecimal unless the --raw option is

       This utility may	be called without a DEVICE but with a  --inhex=FN  op-
       tion  instead. FN is expected to	be a file name (or '-' for stdin). The
       contents	of the file (or	stdin stream) is assumed to be hexadecimal (or
       binary) data that represents a SCSI READ	BUFFER command response	and is
       decoded as such.

       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 re-
	      sponse 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.

       -I, --inhex=FN
	      FN is expected to	be a file name (or '-' for stdin)  which  con-
	      tains ASCII hexadecimal or binary	representing a READ BUFFER re-
	      sponse. If known this utility will then decode that response. It
	      is preferable to also supply the --mode=MO and --specific=MS op-
	      tions, since these are not present in the	response. The hexadec-
	      imal  should  be	arranged  as 1 or 2 digits representing	a byte
	      each of which is whitespace or comma separated.	Anything  from
	      and  including a hash mark to the	end of line is ignored.	If the
	      --raw option is also given then FN is treated as binary.

       -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  be-
	      tween  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.

       -S, --specific=MS
	      this  option  sets  the  mode specific field in the cdb. MS is a
	      value between 0 and 7 as this is a 3 bit field.

       -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.

       rd_microc_st  [15, 0xf]
	      Read microcode status. Added in spc5r20 .

       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.

       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) 2006-2019 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-


sg3_utils-1.45			   May 2019		     SG_READ_BUFFER(8)


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