SGM_DD(8) SG3_UTILS SGM_DD(8) (NAME) sgm_dd - SCSI (SYNOPSIS) sgm_dd [bs=BS] [count=COUNT] [ibs=BS] [if=IFILE] [iflag=FLAGS] [obs=BS] [of=OFILE] [oflag=FLAGS] [seek=SEEK] [skip=SKIP] [--help] [--version] [bpt=BPT] [cdbsz=6|10|12|16] [dio=0|1] [sync=0|1] [time=0|1] [verbose=VERB] [--dry-run] [--nocopy] [--progress] [--verbose] (DESCRIPTION) . <<>> SCSI (sg) . (memory mapped) sg . dd(1) . IFILE OFILE SCSI (sg) . IFILE OFILE sg IFILE . IO OFILE . 'oflag=dio' IO OFILE . IO IO . <<>> dd(1) . . . (OPTIONS) bpt=BPT / BPT ( ). . bs=512 ( ). cd/dvd bpt . bs=BS BS . dd(1) BS . 512 cdrom ( 2048 ) . IO BS * BPT . cdbsz=6 | 10 | 12 | 16 SCSI READ / WRITE sg. SCSI ( SCSI ). count=COUNT COUNT IFILE OFILE. ( IFILE OFILE) sg SCSI READ CAPACITY ( ) . . skip=SKIP seek=SEEK ( ) . COUNT . COUNT . dio=0 | 1 IO ( OFILE) . ( IFILE) sg . << >> ( mmap IO DMA ). . 'dio=1' 'oflag=dio' . ibs=BS BS 'bs=' . if=IFILE IFILE stdin. IFILE '-' stdin . IFILE SKIP . iflag=FLAGS FLAGS . IFILE IFILE stdin . obs=BS BS 'bs=' . of=OFILE OFILE stdout. OFILE '-' stdout . OFILE /dev/null . OFILE '.' () /dev/null ( ). OFILE OFILE 'oflag=append' SEEK . oflag=FLAGS FLAGS . OFILE OFILE /dev/null '.' () stdout . seek=SEEK SEEK bs OFILE. ( ). skip=SKIP SKIP bs IFILE. ( ). sync=0 | 1 SYNCHRONIZE CACHE OFILE . OFILE sg . time=0 | 1 ( stderr) . () . verbose=VERB VERB stderr . . . cdb SCSI ( READ WRITE) . . SCSI ( read() write() ) . -d, --dry-run . IFILE OFILE . . -h, --help . -n, --nocopy OFILE stdout . --nc . IFILE '--of=/dev/null' . '--of=/dev/null' . -p, --progress . <> . . 'time=1' . -v, --verbose verbose=1 . ( "-vv") verbose=2 . -V, --version . (FLAGS) : append O_APPEND OFILE . . seek=SEEK . SEEK SEEK . ( ) . dio oflag ( 'oflag=dio'). 'dio=1' . direct O_DIRECT IFILE / OFILE . IO . . sg . dpo DPO ( ) SCSI READ WRITE. cdb READ WRITE . ( ) . / . dsync O_SYNC IFILE / OFILE . "d" 'sync=0|1' ( ) . excl O_EXCL IFILE / OFILE . fua FUA ( ) SCSI READ / WRITE . sg . SCSI READ WRITE FUA . sg . null . (RETIRED OPTIONS) : fua=0 | 1 | 2 | 3 . fua IFILE OFILE fua IFILE fua OFILE () fua . 'fua' . (NOTES) sgm_dd . raw(8) . sg SCSI lsscsi . fdisk(8) [ <<-ul>> ]. ( SKIP) . <> sg3_utils(8) . count skip seek ( ). . : SCSI DMA sg ( ). sg ( mmap(2) ). () . CPU . stderr dd stdout . . sg SCSI READ WRITE (SBC) CD/DVD/BD . sgm_dd . . << >> sg_dd ( 'coe' ) . (EXAMPLES) sg_dd(8) . (SIGNALS) dd : SIGINT SIGQUIT SIGPIPE + . SIGUSR1 . stderr . (EXIT STATUS) sgm_dd 0 . sg3_utils(8) . 'coe' 'retries' SCSI . (AUTHORS) Douglas Gilbert Peter Allworth. (REPORTING BUGS) . (COPYRIGHT) (C) 2000-2026 Douglas Gilbert GPL . . (SEE ALSO) sg_dd . POSIX sgp_dd sg3_utils . lmbench lmdd . dd(1), ddpt(ddpt), raw(8) sg3_utils-1.49 April 2026 SGM_DD(8)