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41 .Nd magnetic tape manipulating program
50 utility is used to give commands to a magnetic tape drive.
53 performs the requested operation once. Operations
54 may be performed multiple times by specifying
59 must reference a raw (not block) tape device.
61 The available commands are listed below. Only as many
62 characters as are required to uniquely identify a command
64 .Bl -tag -width "eof, weof"
68 end-of-file marks at the current position on the tape.
72 setmarks at the current position on the tape.
98 Read Hardware block position.
99 Some drives do not support this.
101 number reported is specific for that hardware only.
102 The count argument is
105 Read SCSI logical block position.
106 Some drives do not support this.
108 count argument is ignored.
110 Set Hardware block position.
111 Some drives do not support this.
113 argument is interpreted as a hardware block to which to position the tape.
115 Set SCSI logical block position.
116 Some drives do not support this.
118 argument is interpreted as a SCSI logical block to which to position the tape.
122 .It Cm offline , rewoffl
123 Rewind the tape and place the tape unit off-line
127 A count of 0 disables long erase, which is on by default.
130 (one full wind forth and back, Count is ignored).
132 Print status information about the tape unit.
133 For SCSI magnetic tape devices,
134 the current operating modes of density, blocksize, and whether compression
135 is enabled is reported.
136 The current state of the driver (what it thinks that
137 it is doing with the device) is reported.
138 If the driver knows the relative
139 position from BOT (in terms of filemarks and records), it prints that.
141 that this information is not definitive (only BOT, End of Recorded Media, and
142 hardware or SCSI logical block position (if the drive supports such) are
143 considered definitive tape positions).
145 Print (and clear) error status information about this device.
147 operation (e.g., a read or a write) and every control operation (e.g,, a
148 rewind), the driver stores up the last command executed and it's associated
149 status and any residual counts (if any). This command retrieves and prints this
151 If possible, this also clears any latched error information.
153 Set the block size for the tape unit. Zero means variable-length
156 Set the density for the tape unit. For the density codes, see below.
157 The density value could be given either numerically, or as a string,
160 field. If the string is abbreviated, it will be resolved in the order
161 shown in the table, and the first matching entry will be used. If the
162 given string and the resulting canonical density name do not match
163 exactly, an informational message is printed about what the given
164 string has been taken for.
166 Fetch and print out the current EOT filemark model.
168 many filemarks will be written at close if a tape was being written.
173 and print out the current and EOT filemark model.
174 Typically this will be
176 filemarks, but some devices (typically QIC cartridge drives) can
180 Currently you can only choose a value of
185 Forward space to end of recorded medium
188 Forward space to end of data, identical to
191 Set compression mode.
192 There are currently several possible values for the compression mode:
194 .Bl -tag -width 9n -compact
196 Turn compression off.
206 IBM Improved Data Recording Capability compression (0x10).
208 DCLZ compression algorithm (0x20).
211 In addition to the above recognized compression keywords, the user can
212 supply a numeric compression algorithm for the tape drive to use. In most
213 cases, simply turning the compression
215 will have the desired effect of enabling the default compression algorithm
216 supported by the drive. If this is not the case (see the
218 display to see which compression algorithm is currently in use), the user
219 can manually specify one of the supported compression keywords (above), or
220 supply a numeric compression value.
223 If a tape name is not specified, and the environment variable
232 utility returns a 0 exit status when the operation(s) were successful,
233 1 if the command was unrecognized, and 2 if an operation failed.
235 The following density table was taken from the
236 .Sq Historical sequential access density codes
237 table (A-1) in Revision 11 of the SCSI-3 Stream Device Commands (SSC)
238 working draft, dated November 11, 1997.
240 The different density codes are as follows:
242 .Dl "0x0 default for device"
243 .Dl "0xE reserved for ECMA"
244 .Bd -literal -offset 3n
245 Value Width Tracks Density Code Type Reference Note
247 0x01 12.7 (0.5) 9 32 (800) NRZI R X3.22-1983 2
248 0x02 12.7 (0.5) 9 63 (1,600) PE R X3.39-1986 2
249 0x03 12.7 (0.5) 9 246 (6,250) GCR R X3.54-1986 2
250 0x05 6.3 (0.25) 4/9 315 (8,000) GCR C X3.136-1986 1
251 0x06 12.7 (0.5) 9 126 (3,200) PE R X3.157-1987 2
252 0x07 6.3 (0.25) 4 252 (6,400) IMFM C X3.116-1986 1
253 0x08 3.81 (0.15) 4 315 (8,000) GCR CS X3.158-1987 1
254 0x09 12.7 (0.5) 18 1,491 (37,871) GCR C X3.180 2
255 0x0A 12.7 (0.5) 22 262 (6,667) MFM C X3B5/86-199 1
256 0x0B 6.3 (0.25) 4 63 (1,600) PE C X3.56-1986 1
257 0x0C 12.7 (0.5) 24 500 (12,690) GCR C HI-TC1 1,6
258 0x0D 12.7 (0.5) 24 999 (25,380) GCR C HI-TC2 1,6
259 0x0F 6.3 (0.25) 15 394 (10,000) GCR C QIC-120 1,6
260 0x10 6.3 (0.25) 18 394 (10,000) GCR C QIC-150 1,6
261 0x11 6.3 (0.25) 26 630 (16,000) GCR C QIC-320 1,6
262 0x12 6.3 (0.25) 30 2,034 (51,667) RLL C QIC-1350 1,6
263 0x13 3.81 (0.15) 1 2,400 (61,000) DDS CS X3B5/88-185A 5
264 0x14 8.0 (0.315) 1 1,703 (43,245) RLL CS X3.202-1991 5
265 0x15 8.0 (0.315) 1 1,789 (45,434) RLL CS ECMA TC17 5
266 0x16 12.7 (0.5) 48 394 (10,000) MFM C X3.193-1990 1
267 0x17 12.7 (0.5) 48 1,673 (42,500) MFM C X3B5/91-174 1
268 0x18 12.7 (0.5) 112 1,673 (42,500) MFM C X3B5/92-50 1
269 0x19 12.7 (0.5) 128 2,460 (62,500) RLL C DLTapeIII 6,7
270 0x1A 12.7 (0.5) 128 3,214 (81,633) RLL C DLTapeIV(20) 6,7
271 0x1B 12.7 (0.5) 208 3,383 (85,937) RLL C DLTapeIV(35) 6,7
272 0x1C 6.3 (0.25) 34 1,654 (42,000) MFM C QIC-385M 1,6
273 0x1D 6.3 (0.25) 32 1,512 (38,400) GCR C QIC-410M 1,6
274 0x1E 6.3 (0.25) 30 1,385 (36,000) GCR C QIC-1000C 1,6
275 0x1F 6.3 (0.25) 30 2,666 (67,733) RLL C QIC-2100C 1,6
276 0x20 6.3 (0.25) 144 2,666 (67,733) RLL C QIC-6GB(M) 1,6
277 0x21 6.3 (0.25) 144 2,666 (67,733) RLL C QIC-20GB(C) 1,6
278 0x22 6.3 (0.25) 42 1,600 (40,640) GCR C QIC-2GB(C) ?
279 0x23 6.3 (0.25) 38 2,666 (67,733) RLL C QIC-875M ?
280 0x24 3.81 (0.15) 1 2,400 (61,000) CS DDS-2 5
281 0x25 3.81 (0.15) 1 3,816 (97,000) CS DDS-3 5
282 0x26 3.81 (0.15) 1 3,816 (97,000) CS DDS-4 5
283 0x27 8.0 (0.315) 1 3,056 (77,611) RLL CS Mammoth 5
284 0x28 12.7 (0.5) 36 1,491 (37,871) GCR C X3.224 1
287 0x2B 12.7 (0.5) 3 ? ? ? C X3.267 5
288 0x41 12.7 (0.5) 208 3,868 (98,250) RLL C DLTapeIV(40) 6,7
289 0x48 12.7 (0.5) 448 5,236 (133,000) PRML C SDLTapeI(110) 6,8
290 0x49 12.7 (0.5) 448 7,598 (193,000) PRML C SDLTapeI(160) 6,8
292 .Bd -literal -offset 3n
293 Code Description Type Description
294 ---------------- ----------------
295 NRZI Non return to zero, change on ones R Reel-to-reel
296 GCR Group code recording C Cartridge
297 PE Phase encoded CS Cassette
298 IMFM Inverted modified frequency modulation
299 MFM Modified frequency modulation
301 RLL Run length limited
302 PRML Partial Response Maximum Likelihood
304 .Bd -literal -offset 3n
307 2. Parallel recorded.
308 3. Old format known as QIC-11.
310 6. This is not an American National Standard. The reference is based on
311 an industry standard definition of the media format.
312 7. DLT recording: serially recorded track pairs (DLTapeIII and
313 DLTapeIV(20)), or track quads (DLTapeIV(35) and DLTapeIV(40)).
314 8. Super DLT (SDLT) recording: 56 serially recorded logical tracks with
315 8 physical tracks each.
318 If the following environment variable exists, it is utilized by
326 environment variable if the
332 .Bl -tag -width /dev/*rst[0-9]*xx -compact
333 .It Pa /dev/*rsa[0-9]*
334 SCSI magnetic tape interface
348 Extensions regarding the
354 command, and have been merged into the
361 command that used to be a synonym for
363 has been abandoned in
365 since it was often confused with
367 which is fairly dangerous.