1SG_TURS(8) SG3_UTILS SG_TURS(8)
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6 sg_turs - send one or more SCSI TEST UNIT READY commands
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9 sg_turs [--delay=MS] [--help] [--low] [--num=NUM] [--number=NUM]
10 [--progress] [--time] [--verbose] [--version] DEVICE
11 sg_turs [-d=MS] [-n=NUM] [-p] [-t] [-v] [-V] DEVICE
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15 This utility sends one or more SCSI TEST UNIT READY commands to the DE‐
16 VICE. This may be useful for timing the per command overhead. Note
17 that TEST UNIT READY has no associated data, just a 6 byte command
18 (with each byte a zero) and a returned SCSI status value.
19 This utility supports two command line syntaxes, the preferred one is
21 shown first in the synopsis and explained in this section. A later sec‐
22 tion on the old command line syntax outlines the second group of op‐
23 tions.
24
26 Arguments to long options are mandatory for short options as well.
27 -d, --delay=MS
29 this option causes a delay of MS milliseconds to occur before
30 each TEST UNIT READY command is issued.
31 -h, --help
33 print out the usage message then exit.
34 -l, --low
36 when [--progress] is not being used, this utility tries to com‐
37 plete the SCSI TEST UNIT READY command(s) as quickly as possi‐
38 ble. Usually it calls a library function to do each TUR
39 (sg_ll_test_unit_ready). With this option it uses the lower
40 level sg_pt interface (see sg_pt.h) to save a little time on
41 each TUR.
42 -n, --num=NUM
44 performs TEST UNIT READY NUM times. If not given defaults to 1.
45 These suffix multipliers are permitted: c C *1; w W *2; b B
46 *512; k K KiB *1,024; KB *1,000; m M MiB *1,048,576; MB
47 *1,000,000; g G GiB *1,073,741,824; and GB *1,000,000,000 . Also
48 a suffix of the form "x<n>" multiplies the leading number by
49 <n>. Alternatively a hex number may be given, prefixed by either
50 '0x' or has a trailing 'h'.
51 --number=NUM
53 same as --num=NUM. Added for compatibility with sg_requests and
54 other utilities in this package. The sg_request utility has
55 taken over the role of polling the progress indication which was
56 originally assigned to the TEST UNIT READY command. This is a
57 change by T10.
58 -O, --old
60 Switch to older style options. Please use as first option.
61 -p, --progress
63 show progress indication (a percentage) if available. If
64 --num=NUM is given, NUM is greater than 1 and an initial
65 progress indication was detected then this utility waits 30 sec‐
66 onds before subsequent checks. If the --delay=MS option is
67 given then it will wait for that number of milliseconds instead
68 of 30 seconds. Exits when NUM is reached or there are no more
69 progress indications. Ignores --time option. See NOTES section
70 below.
71 -t, --time
73 after completing the requested number of TEST UNIT READY com‐
74 mands, outputs the total duration and the average number of com‐
75 mands executed per second.
76 -v, --verbose
78 increase level or verbosity.
79 -V, --version
81 print version string then exit.
82
84 The progress indication is optionally part of the sense data. When a
85 prior command that takes a long time to complete (and typically pre‐
86 cludes other media access commands) is still underway, the progress in‐
87 dication can be used to determine how long before the device returns to
88 its normal state. Around SPC-3 T10 changed the preferred command for
89 polling the progress indication from TEST UNIT READY to REQUEST SENSE
90 (see the sg_requests utility).
91 The SCSI FORMAT command for disks used with the IMMED bit set is an ex‐
93 ample of an operation that takes a significant amount of time and pre‐
94 cludes other media access during that time. The IMMED bit set instructs
95 the FORMAT command to return control to the application client once the
96 format has commenced (see SBC-3). Several long duration SCSI commands
97 associated with tape drives also use the progress indication (see
98 SSC-3).
99 The DEVICE is opened with a read-only flag (e.g. in Unix with the
101 O_RDONLY flag).
102 Early standards suggested that the SCSI TEST UNIT READY command be used
104 for polling the progress indication. More recent standards seem to sug‐
105 gest the SCSI REQUEST SENSE command should be used instead.
106
108 The exit status of sg_turs is 0 when it is successful (e.g. in the case
109 of a mechanical disk, it is spun up and ready to accept commands). For
110 this utility the other exit status of interest is 2 corresponding to
111 the "not ready" sense key. For other exit status values see the
112 sg3_utils(8) man page.
113
115 The options in this section were the only ones available prior to
116 sg3_utils version 1.23 . Since then this utility defaults to the newer
117 command line options which can be overridden by using --old (or -O) as
118 the first option. See the ENVIRONMENT VARIABLES section for another way
119 to force the use of these older command line options.
120 -d, --delay=MS
122 this option causes a delay of MS milliseconds to occur before
123 each TEST UNIT READY command is issued.
124 -n=NUM performs TEST UNIT READY NUM times. If not given defaults to 1.
126 Equivalent to --num=NUM in the main description.
127 -N, --new
129 Switch to the newer style options.
130 -p show progress indication (a percentage) if available. Equiva‐
132 lent to --progress in the main description.
133 -t after completing the requested number of TEST UNIT READY com‐
135 mands, outputs the total duration and the average number of com‐
136 mands executed per second. Equivalent to --time in the main de‐
137 scription.
138 -v increase level of verbosity.
140 -V print out version string then exit.
142
144 Since sg3_utils version 1.23 the environment variable
145 SG3_UTILS_OLD_OPTS can be given. When it is present this utility will
146 expect the older command line options. So the presence of this environ‐
147 ment variable is equivalent to using --old (or -O) as the first command
148 line option.
149
151 Written by D. Gilbert
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154 Copyright © 2000-2020 Douglas Gilbert
155 This software is distributed under the GPL version 2. There is NO war‐
156 ranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR‐
157 POSE.
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160 sg_inq, sg_requests (sg3_utils)
161sg3_utils-1.46 July 2020 SG_TURS(8)