sg_read: : 1.25 20160121

Usage: sg_read [blk_sgio=0|1] [bpt=BPT] [bs=BS] [cdbsz=6|10|12|16] count=COUNT [dio=0|1] [dpo=0|1] [fua=0|1] if=IFILE [mmap=0|1] [no_dfxer=0|1] [odir=0|1] [skip=SKIP] [time=TI] [verbose=VERB] [--help] [--version] where: blk_sgio 0->normal IO for block devices, 1->SCSI commands via SG_IO bpt is blocks_per_transfer (default is 128, or 64 KiB for default BS) setting 'bpt=0' will do COUNT zero block SCSI READs bs must match sector size if IFILE accessed via SCSI commands (def=512) cdbsz size of SCSI READ command (default is 10) count total bytes read will be BS*COUNT (if no error) (if negative, do |COUNT| zero block SCSI READs) dio 1-> attempt direct IO on sg device, 0->indirect IO (def) dpo 1-> set disable page out (DPO) in SCSI READs fua 1-> set force unit access (FUA) in SCSI READs if an sg, block or raw device, or a seekable file (not stdin) mmap 1->perform mmaped IO on sg device, 0->indirect IO (def) no_dxfer 1->DMA to kernel buffers only, not user space, 0->normal(def) odir 1->open block device O_DIRECT, 0->don't (def) skip each transfer starts at this logical address (def=0) time 0->do nothing(def), 1->time from 1st cmd, 2->time from 2nd, ... verbose increase level of verbosity (def: 0) --help print this usage message then exit --version print version number then exit Issue SCSI READ commands, each starting from the same logical block address