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SG_IDENT(8)			   SG3_UTILS			   SG_IDENT(8)

NAME
       sg_ident	- send SCSI REPORT/SET IDENTIFYING INFORMATION command

SYNOPSIS
       sg_ident	 [--ascii]  [--clear]  [--help]	 [--itype=IT]  [--raw] [--set]
       [--verbose] [--version] DEVICE

DESCRIPTION
       Send a SCSI REPORT IDENTIFYING INFORMATION or SET IDENTIFYING  INFORMA-
       TION command to DEVICE. Prior to	SPC-4 (revision	7) these commands were
       called REPORT DEVICE IDENTIFIER and SET DEVICE IDENTIFIER respectively.
       SCSI devices that support these two commands allow users	to write (set)
       identifying information and report it back at some later	time. The  in-
       formation is persistent (i.e. stored on some non-volatile medium	within
       the SCSI	device that will survive a power outage).

       Typically the space allocated for the  information  is  limited:	 SPC-4
       (revision  7) states that for information type 0, the minimum length is
       64 bytes	and the	maximum	is 512 bytes. For other	information  types  (1
       to  126	inclusive)  the	 maximum length	is 256 bytes. Also information
       types 1 to 126 (inclusive)  should  contain  a  null  terminated	 UTF-8
       string. The author has seen older disks that only support 16 bytes.

       The  default  action  when no options are given is to invoke the	Report
       Identifying Information command with the	information type defaulting to
       zero.  Error  reports are sent to stderr. By default the	information is
       shown in	ASCII-HEX (up to 16 bytes per line) with an ASCII  representa-
       tion to the right with dots replacing non printable characters.

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

       -A, --ascii
	      invokes  the  Report Identifying Information command and if any-
	      thing is found interprets	it as ASCII (or	UTF-8 which is	locale
	      dependent) and prints the	information to stdout.

       -C, --clear
	      invokes the Set Identifying Information command with an informa-
	      tion length of zero. This	has the	effect of clearing the	exist-
	      ing information.

       -h, --help
	      output the usage message then exit.

       -i, --itype=IT
	      where  IT	is the information type. Defaults to zero. The maximum
	      value is 127 which is special and	cannot be used with  --set  or
	      --clear.	The  information type of 127 (if supported) causes the
	      REPORT IDENTIFYING INFORMATION command to	respond	with a list of
	      available	 information types and their maximum lengths in	bytes.
	      The odd numbered information types between 3 and 125 (inclusive)
	      are not to be used (as they clash	with the SCC-2 standard).

       -r, --raw
	      invokes  the  Report Identifying information command and if any-
	      thing is found sends the information (which may  be  binary)  to
	      stdout. Nothing else is sent to stdout however error reports, if
	      any, are sent to stderr.

       -S, --set
	      first reads stdin	until an EOF is	detected then invokes the  Set
	      Identifying  Information	command	 to  set what has been fetched
	      from stdin as the	information. The amount	of data	read  must  be
	      between 1	and 512	bytes length (inclusive).

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

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

       This  utility  permits users to write their own identifying information
       to their	SCSI devices. There are	several	other types of descriptors (or
       designators)  that  the	user cannot change. These include the SCSI IN-
       QUIRY command with  its	standard  vendor  and  product	identification
       strings and the product revision	level; plus the	large amount of	infor-
       mation provided by the "Device Identification" VPD page	(see  sg_vpd).
       There  is  also the READ	MEDIA SERIAL NUMBER command (see sg_rmsn). The
       MMC-4 command set for CD	and DVDs has a "media serial  number"  feature
       (0x109)	[and  a	 "logical  unit	 serial	number"	feature]. These	can be
       viewed with the sg_get_config utility.

EXAMPLES
       First, to see if	there is an existing information whose format  is  un-
       known (for information type 0), use no options:

	 # sg_ident /dev/sdb
	  00	 31 32 33 34 35	36 37 38  39 30		 1234567890

       If it is	ASCII then it can printed as such:

	 # sg_ident --ascii /dev/sdb
	 1234567890

       The  information	 can be	copied to a file, cleared and then re-asserted
       with this sequence:

	 # sg_ident --raw /dev/sdb > t
	 # sg_ident --clear /dev/sdb
	 # cat t | sg_ident --set /dev/sdb

EXIT STATUS
       The exit	status of sg_ident 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 (C) 2005-2018 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-
       POSE.

SEE ALSO
       sg_vpd(sg3_utils), sg_rmsn(sg3_utils), sg_get_config(sg3_utils)

sg3_utils-1.43			  August 2018			   SG_IDENT(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | EXIT STATUS | AUTHORS | REPORTING BUGS | COPYRIGHT | SEE ALSO

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