/usr/bin/sg_dd

Usage: sg_dd  [bs=BS] [conv=CONV] [count=COUNT] [ibs=BS] [if=IFILE]
              [iflag=FLAGS] [obs=BS] [of=OFILE] [oflag=FLAGS] [seek=SEEK]
              [skip=SKIP] [--dry-run] [--help] [--verbose] [--version]

              [blk_sgio=0|1] [bpt=BPT] [cdbsz=6|10|12|16] [cdl=CDL]
              [coe=0|1|2|3] [coe_limit=CL] [dio=0|1] [grpnum=GN]
              [odir=0|1] [of2=OFILE2] [retries=RETR] [sync=0|1]
              [time=0|1[,TO]] [verbose=VERB] [--compare] [--progress]
              [--verify]
  where:
    blk_sgio    0->block device use normal I/O(def), 1->use SG_IO
    bpt         is blocks_per_transfer (default is 128 or 32 when BS>=2048)
    bs          logical block size (default is 512)
    cdbsz       size of SCSI READ or WRITE cdb (default is 10)
    cdl         command duration limits value 0 to 7 (def: 0 (no cdl))
    coe         0->exit on error (def), 1->continue on sg error (zero
                fill), 2->also try read_long on unrecovered reads,
                3->and set the CORRCT bit on the read long
    coe_limit   limit consecutive 'bad' blocks on reads to CL times
                when COE>1 (default: 0 which is no limit)
    conv        comma separated list from: [nocreat,noerror,notrunc,
                null,sparse,sync]
    count       number of blocks to copy (def: device size)
    dio         for direct IO, 1->attempt, 0->indirect IO (def)
    grpnum      field in SCSI READ and WRITE commands (def: 0)
    ibs         input logical block size (if given must be same as 'bs=')
    if          file or device to read from (def: stdin)
    iflag       comma separated list from: [00,coe,dio,direct,dpo,dsync,
                excl,ff,flock,fua,nocache,null,pt,random,sgio]
    obs         output logical block size (if given must be same as 'bs=')
    odir        1->use O_DIRECT when opening block dev, 0->don't(def)
    of          file or device to write to (def: stdout), OFILE of '.'
                treated as /dev/null
    of2         additional output file (def: /dev/null), OFILE2 should be
                normal file or pipe
    oflag       comma separated list from: [append,coe,dio,direct,dpo,
                dsync,excl,flock,fua,nocache,nocreat,null,pt,sgio,sparse]
    retries     retry sgio errors RETR times (def: 0)
    seek        block position to start writing to OFILE
    skip        block position to start reading from IFILE
    sync        0->no sync(def), 1->SYNCHRONIZE CACHE on OFILE after copy
    time        0->no timing(def), 1->time plus calculate throughput;
                TO is command timeout in seconds (def: 60)
    verbose     0->quiet(def), 1->some noise, 2->more noise, etc
    --compare|-c    same as --verify, compare IFILE with OFILE
    --dry-run|-d    do preparation but bypass copy (or read)
    --help|-h    print out this usage message then exit
    --progress|-p    print progress report every 2 minutes
    --verbose|-v   same as 'verbose=1', can be used multiple times
    --verify|-x    do verify/compare rather than copy (OFILE must
                   be a sg device)
    --version|-V    print version information then exit

Copy from IFILE to OFILE, similar to dd command; specialized for SCSI
devices. If the --verify option is given then IFILE is read and that data
is used to compare with OFILE using the VERIFY(n) SCSI command (with
BYTCHK=1).
Can't have both 'if' as stdin _and_ 'of' as stdout
For more information use '--help'