SCUZZ(8) System Manager's Manual 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 target. On successful completion of a com-
mand, 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 commands, 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 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 com-
mand that had check-condition status. 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.
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 information 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 format.
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.
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), 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.
SCUZZ(8)