bionic (8) sg_turs.8.gz

NAME

       sg_turs - send one or more SCSI TEST UNIT READY commands

SYNOPSIS

       sg_turs [--help] [--number=NUM] [--progress] [--time] [--verbose] [--version] DEVICE

       sg_turs [-n=NUM] [-p]  [-t] [-v] [-V] DEVICE

DESCRIPTION

       This utility sends one or more SCSI TEST UNIT READY commands to the DEVICE. This may be useful for timing
       the per command overhead.  Note that TEST UNIT READY has no associated data, just a 6 byte command and  a
       returned SCSI status value.

       This  utility  supports  two  command line syntaxes, the preferred one is shown first in the synopsis and
       explained in this section. A later section on the old command line syntax outlines the  second  group  of
       options.

OPTIONS

       Arguments to long options are mandatory for short options as well.

       -h, --help
              print out the usage message then exit.

       -n, --number=NUM
              performs  TEST  UNIT  READY  NUM  times. If not given defaults to 1.  These suffix multipliers are
              permitted: c C *1; w W *2; b B *512; k K KiB *1,024; KB *1,000; m M MiB *1,048,576; MB *1,000,000;
              g  G  GiB  *1,073,741,824; and GB *1,000,000,000 . Also a suffix of the form "x<n>" multiplies the
              leading number by <n>. Alternatively a hex number may be given, prefixed by either '0x' or  has  a
              trailing 'h'.

       -O, --old
              switch to older style options.

       -p, --progress
              show  progress  indication  (a  percentage) if available. If --number=NUM is given, NUM is greater
              than 1 and an initial progress indication was detected then this utility waits 30  seconds  before
              subsequent  checks.  Exits when NUM is reached or there are no more progress indications.  Ignores
              --time option. See NOTES section below.

       -t, --time
              after completing the requested number of TEST UNIT READY commands, outputs the total duration  and
              the average number of commands executed per second.

       -v, --verbose
              increase level or verbosity.

       -V, --version
              print version string then exit.

NOTES

       The progress indication is optionally part of the sense data. When a prior command that takes a long time
       to complete (and typically precludes other  media  access  commands)  is  still  underway,  the  progress
       indication can be used to determine how long before the device returns to its normal state.

       The  SCSI FORMAT command for disks used with the IMMED bit set is an example of an operation that takes a
       significant amount of time and precludes other media access during that time. The IMMED bit set instructs
       the FORMAT command to return control to the application client once the format has commenced (see SBC-3).
       Several long duration SCSI commands associated with tape drives also use  the  progress  indication  (see
       SSC-3).

       The DEVICE is opened with a read-only flag (e.g. in Unix with the O_RDONLY flag).

       Early  standards  suggested  that  the  SCSI  TEST  UNIT  READY  command be used for polling the progress
       indication. More recent standards seem to suggest the SCSI REQUEST SENSE command should be used instead.

EXIT STATUS

       The exit status of sg_turs is 0 when it is successful (e.g. in the case of a mechanical disk, it is  spun
       up  and  ready to accept commands). For this utility the other exit status of interest is 2 corresponding
       to the "not ready" sense key. For other exit status values see the sg3_utils(8) man page.

OLDER COMMAND LINE OPTIONS

       The options in this section were the only ones available prior to sg3_utils version 1.23 .  In  sg3_utils
       version  1.23  and  later  these  older  options can be selected by either setting the SG3_UTILS_OLD_OPTS
       environment variable or using '--old' (or '-O) as the first option.

       -n=NUM performs TEST UNIT READY NUM times. If not given defaults to 1.  Equivalent to --number=NUM in the
              main description.

       -N     switch to the newer style options.

       -p     show  progress  indication  (a  percentage)  if  available.   Equivalent to --progress in the main
              description.

       -t     after completing the requested number of TEST UNIT READY commands, outputs the total duration  and
              the average number of commands executed per second.  Equivalent to --time in the main description.

       -v     increase level of verbosity.

       -V     print out version string then exit.

AUTHORS

       Written by D. Gilbert

COPYRIGHT

       Copyright © 2000-2014 Douglas Gilbert
       This  software is distributed under the GPL version 2. There is NO warranty; not even for MERCHANTABILITY
       or FITNESS FOR A PARTICULAR PURPOSE.

SEE ALSO

       sg_inq, sg_request (sg3_utils)