SCUZZ(8) SCUZZ(8)
NAME
scuzz - SCSI target control
SYNOPSIS
scuzz [ -q ] [ target-id ]
DESCRIPTION
Scuzz is an interactive program for exercising raw SCSI
devices. It reads commands from standard input and applies
them to a SCSI target. If target-id is given on the command
line, an open (see below) is immediately applied to the tar-
get. On successful completion of a command, ok n is
printed, where n is the number of bytes transferred to/from
the target; the -q command line option suppresses the ok
message.
Commands
help command
Help is rudimentary and prints a one line synopsis for
the named command, or for all commands if no argument
is given.
probe
Probe attempts an inquiry command on all SCSI target
ids, and prints the result preceded by the id of those
targets which respond.
The help and probe commands may be given at any time.
open target-id
Open must be given before any of the remaining commands
will be accepted. Internally, open issues ready then
inquiry, followed by a device class-specific command to
determine the logical block size of the target.
close
Close need only be given if another target is to be
opened in the current session.
The remaining commands are in two groups, generic SCSI com-
mands, and those specific to the Philips CDD521 Compact Disc
Recorder (flushcache onwards). With the exception of the
read, write, space, and wtrack commands, all arguments are
in the style of ANSI-C integer constants.
ready
Test Unit Ready checks if the unit is powered up and
ready to do read and write commands.
rezero
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SCUZZ(8) SCUZZ(8)
Rezero Unit requests that a disc be brought to a known
state, usually by seeking to track zero.
rewind
Rewind positions a tape at the beginning of current
partition (there is usually only one partition, the
beginning of tape).
reqsense
Request Sense retrieves Sense Data concerning an error
or other condition and is usually issued following the
completion of a command that had check-condition sta-
tus. Scuzz automatically issues a reqsense in response
to a check-condition status and prints the result.
format
Format Unit performs a ``low level'' format of a disc.
rblimits
Read Block Limits reports the possible block lengths
for the logical unit. Tapes only.
read file nbytes
Read transfers data from the target to the host. A
missing nbytes causes the entire device to be read.
write file nbytes
Write transfers data from the host to the target. A
missing nbytes causes the entire input file to be
transferred.
The first argument to the read, write, and wtrack
(q.v.) commands specifies a source (write and wtrack)
or destination (read) for the I/O. The argument is
either a plain file name or | followed by a command to
be executed by rc(1). The argument may be quoted in the
style of rc(1).
seek offset whence
Seek requests the target to seek to a position on a
disc, arguments being in the style of seek(2); whence
is 0 by default.
Scuzz maintains an internal notion of where the current
target is positioned. The seek, read, write, rewind,
rezero, and wtrack commands all manipulate the internal
offset.
filemark howmany
Write Filemarks writes one (default) or more filemarks
on a tape.
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SCUZZ(8) SCUZZ(8)
space [-b] [-f] [[--]howmany]
Space positions a tape forwards or backwards. The
arguments specify logical block (-b) or filemark (-f)
spacing; default is -b. If howmany is negative it
specifies spacing backwards, and should be preceded by
-- to turn off any further option processing. Default
is 1.
inquiry
Inquiry is issued to determine the device type of a
particular target, and to determine some basic informa-
tion about the implemented options and the product
name.
modeselect bytes...
Mode Select is issued to set variable parameters in the
target. Bytes given as arguments comprise all the data
for the target; see an appropriate manual for the for-
mat.
modesense [page [nbytes]]
Mode Sense reports variable and fixed parameters from
the target. If no page is given, all pages are
returned. Nbytes specifies how many bytes should be
returned.
start code
stop code
eject code
Start, stop, and eject are synonyms for Start/Stop Unit
with different default values of code. Start/Stop Unit
is typically used to spin up and spin down a rotating
disk drive. Code is 0 to stop, 1 to start and 3 to
eject (if the device supports ejection of the medium).
capacity
Read Capacity reports the number of blocks and the
block size of a disc.
The remaining commands are specific to the CDD521 Compact
Disc Recorder. A brief description of each is given; see
the manual for details of arguments.
flushcache
The Flush Cache command forces data in the cache memory
of the CDD521 to be written to the physical medium.
rdiscinfo [track/session-number[ses]]
The Read TOC/PMA command transfers data from one of the
tables of contents (TOC or PMA) on the CD medium.
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SCUZZ(8) SCUZZ(8)
fwaddr [track[mode[npa]]]
The First Writable Address command reports the next
logical writable address for the next write command.
treserve nbytes
The Reserve Track command reserves one track on the
disc. Tracks can only be reserved in successive order.
trackinfo track
Read Track Info reports the starting address, the
length of a given track on the disc and the number of
free blocks in that track.
wtrack file [nbytes [track [mode]]]
Write Track sets up for track-writing if nbytes is 0
(default), or writes a complete track. See write
above.
load
unload
Load and Unload open or close the tray.
fixation [toc-type]
Fixation writes table of contents (TOC) and LEADOUT
information to the disc to complete a session.
FILES
#S/scsi-target-id/cmd raw SCSI interface for command and
status.
#S/scsi-target-id/data raw SCSI interface for I/O.
SOURCE
/sys/src/cmd/scuzz
SEE ALSO
scsi(3)
Small Computer System Interface - 2 (X3T9.2/86-109), .}f
Global Engineering Documents
SCSI Command Set CDD521/10, Philips IMS
SCSI Bench Reference, ENDL Publications
BUGS
Only a limited subset of SCSI commands has been implemented
(as needed).
Only one target can be open at a time.
LUNs other than 0 are not supported.
No way to force 6- or 10- byte commands.
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