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diff --git a/static/freebsd/man1/mt.1 b/static/freebsd/man1/mt.1 new file mode 100644 index 00000000..361c9ae6 --- /dev/null +++ b/static/freebsd/man1/mt.1 @@ -0,0 +1,700 @@ +.\" Copyright (c) 1981, 1990, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.Dd March 2, 2026 +.Dt MT 1 +.Os +.Sh NAME +.Nm mt +.Nd magnetic tape manipulating program +.Sh SYNOPSIS +.Nm +.Op Fl f Ar tapename +.Ar command +.Op Ar count +.Nm +.Op Fl f Ar tapename +.Ar command +.Ar argument +.Sh DESCRIPTION +The +.Nm +utility is used to command a magnetic tape drive for operations +other than reading or writing data. +.Pp +The +.Fl f +option's +.Ar tapename +overrides the +.Ev TAPE +environment variable described below. +.Pp +The available commands are listed below. +Only as many +characters as are required to uniquely identify a command +need be specified. +.Pp +The following commands optionally take a +.Ar count , +which defaults to 1. +.Bl -tag -width ".Cm erase" +.It Cm weof +Write +.Ar count +end-of-file (EOF) marks at the current position. +This returns when the file mark has been written to the media. +.It Cm weofi +Write +.Ar count +end-of-file (EOF) marks at the current position. +This returns as soon as the command has been validated by the tape drive. +.It Cm smk +Write +.Ar count +setmarks at the current position (DDS drives only). +.It Cm fsf +Forward space +.Ar count +files. +.It Cm fsr +Forward space +.Ar count +records. +.It Cm fss +Forward space +.Ar count +setmarks (DDS drives only). +.It Cm bsf +Backward space +.Ar count +files. +.It Cm bsr +Backward space +.Ar count +records. +.It Cm bss +Backward space +.Ar count +setmarks (DDS drives only). +.It Cm erase +Erase the tape using a long (often very long) method. +With a +.Ar count +of 0, it will erase the tape using a quick method. +Operation is not guaranteed if the tape is not at its beginning. +The tape will be at its beginning upon completion. +.El +.Pp +The following commands ignore +.Ar count . +.Bl -tag -width ".Cm geteotmodel" +.It Cm rdhpos +Read the hardware block position. +The block +number reported is specific for that hardware only. +With drive data compression especially, +this position may have more to do with the amount of data +sent to the drive than the amount of data written to tape. +Some drives do not support this. +.It Cm rdspos +Read the SCSI logical block position. +This typically is greater than the hardware position +by the number of end-of-file marks. +Some drives do not support this. +.It Cm rewind +Rewind the tape. +.It Cm offline , rewoffl +Rewind the tape and place the drive off line. +Some drives are never off line. +.It Cm load +Load the tape into the drive. +.It Cm retension +Re-tension the tape. +This winds the tape from the current position to the end +and then to the beginning. +This sometimes improves subsequent reading and writing, +particularly for streaming drives. +Some drives do not support this. +.It Cm ostatus +Output status information about the drive. +For SCSI magnetic tape devices, +the current operating modes of density, blocksize, and whether compression +is enabled is reported. +The current state of the driver (what it thinks that +it is doing with the device) is reported. +If the driver knows the relative +position from BOT (in terms of filemarks and records), it outputs that. +Note +that this information is not definitive (only BOT, End of Recorded Media, and +hardware or SCSI logical block position (if the drive supports such) are +considered definitive tape positions). +.Pp +Also note that this is the old status command, and will be eliminated in +favor of the new status command (see below) in a future release. +.It Cm errstat +Output (and clear) error status information about this device. +For every normal +operation (e.g., a read or a write) and every control operation (e.g,, a +rewind), the driver stores up the last command executed and it is associated +status and any residual counts (if any). +This command retrieves and outputs this +information. +If possible, this also clears any latched error information. +.It Cm geteotmodel +Output the current EOT filemark model. +The model states how +many filemarks will be written at close if a tape was being written. +.It Cm eod , eom +Wind the tape to the end of the recorded data, +typically after an EOF mark where another file may be written. +.It Cm rblim +Report the block limits of the tape drive, including the minimum and +maximum block size, and the block granularity if any. +.El +.Pp +The following commands may require an +.Ar argument . +.Bl -tag -width ".Cm seteotmodel" +.It Cm sethpos +Set the hardware block position. +The +.Ar argument +is a hardware block number to which to position the tape. +Some drives do not support this. +.It Cm setspos +Set the SCSI logical block position. +The +.Ar argument +is a SCSI logical block number to which to position the tape. +Some drives do not support this. +.It Cm blocksize +Set the block size for the drive. +The +.Ar argument +is the number of bytes per block, +except 0 commands the drive to use variable-length blocks. +.It Cm seteotmodel +Set the EOT filemark model to +.Ar argument +and output the old and new models. +Typically this will be 2 +filemarks, but some devices (typically QIC cartridge drives) can +only write 1 filemark. +You may only choose a value of +.Ar 1 +or +.Ar 2 . +.It Cm status +Output status information about the drive. +For SCSI magnetic tape devices, +the current operating modes of density, blocksize, and whether compression +is enabled is reported. +The current state of the driver (what it thinks that +it is doing with the device) is reported. +.Pp +If the driver knows the relative +position from BOT (in terms of filemarks and records), it outputs that. +If the tape drive supports the long form report of the +.Tn SCSI +READ POSITION command, the Reported File Number and Reported Record Number +will be numbers other than -1, and there may be Flags reported as well. +.Pp +The BOP flag means that the logical position of the drive is at the +beginning of the partition. +.Pp +The EOP flag means that the logical position of the drive is between Early +Warning and End of Partition. +.Pp +The BPEW flag means that the logical position of the drive is in a +Programmable Early Warning Zone or on the EOP side of Early Warning. +.Pp +Note that the Reported Record Number is the tape block or object number +relative to the beginning of the partition. +The Calculated Record Number is the tape block or object number relative +to the previous file mark. +.Pp +Note +that the Calculated File and Record Numbers are not definitive. +The Reported File and Record Numbers are definitive, if they are numbers +other than -1. +.Bl -tag -width 6n +.It Fl v +Print additional status information, such as the maximum supported I/O +size. +.It Fl x +Print all available status data to stdout in XML format. +.El +.It Cm getdensity +Report density support information for the tape drive and any media that is +loaded. +Most drives will report at least basic density information similar to that +reported by +.Nm status +command. +Newer tape drives that conform to the T-10 SSC and newer tape +specifications may report more detailed information about the types of +tapes they support and the tape currently in the drive. +.Bl -tag -width 6n +.It Fl x +Print all available density data to stdout in XML format. +Because density information is currently included in the general status XML +report used for +.Nm +status command, this will be the same XML output via +.Do +.Nm +status +.Fl x +.Dc +.El +.It Cm param +Display or set parameters. +One of +.Fl l , +.Fl s , +or +.Fl x +must be specified to indicate which operation to perform. +See +.Xr sa 4 +for more detailed information on the parameters. +.Bl -tag -width 8n +.It Fl l +List parameters, values and descriptions. +By default all parameters will be displayed. +To display a specific parameter, specify the parameter with +.Fl p . +.It Fl p Ar name +Specify the parameter name to list (with +.Fl l ) +or set (with +.Fl s ) . +.It Fl q +Enable quiet mode for parameter listing. +This will suppress printing of parameter descriptions. +.It Fl s Ar value +Specify the parameter value to set. +The general type of this argument (integer, unsigned integer, string) is +determined by the type of the variable indicated by the +.Xr sa 4 +driver. +More detailed argument checking is done by the +.Xr sa 4 +driver. +.It Fl x +Print out all parameter information in XML format. +.El +.It Cm protect +Display or set drive protection parameters. +This is used to control checking and reporting a per-block checksum for +tape drives that support it. +Some drives may only support some parameters. +.Bl -tag -width 8n +.It Fl b Ar 0|1 +Set the Recover Buffered Data Protected bit. +If set, this indicates that checksums are transferred with the logical +blocks transferred by the RECOVERED BUFFERED DATA +.Tn SCSI +command. +.It Fl d +Disable all protection information settings. +.It Fl e +Enable all protection information settings. +The default protection method used is Reed-Solomon CRC (protection method +1), as specified in ECMA-319. +The default protection information length used with Reed-Solomon CRC is +4 bytes. +To enable all settings except one more setting, specify the +.Fl e +argument and then explicitly disable settings that you do not wish to +enable. +For example, specifying +.Fl e +.Fl w Ar 0 +will enable all settings except for LBP_W. +.It Fl l +List available protection parameters and their current settings. +.It Fl L Ar len +Set the length of the protection information in bytes. +For Reed-Solomon CRC, the protection information length should be 4 bytes. +.It Fl m Ar num +Specify the numeric value for the protection method. +The numeric value for Reed-Solomon CRC is 1. +.It Fl r Ar 0|1 +Set the LBP_R parameter. +When set, this indicates that each block read from the tape drive will +have a checksum at the end. +.It Fl v +Enable verbose mode for parameter listing. +This will include descriptions of each parameter. +.It Fl w Ar 0|1 +Set the LBP_W parameter. +When set, this indicates that each block written to the tape drive will have +a checksum at the end. +The drive will verify the checksum before writing the block to tape. +.El +.It Cm locate +Set the tape drive's logical position. +One of +.Fl b , +.Fl e , +.Fl f , +or +.Fl s +must be specified to indicate the type of position. +If the partition number is specified, the drive will first relocate to the +given partition (if it exists) and then to the position indicated within +that partition. +If the partition number is not specified, the drive will relocate to the +given position within the current partition. +.Bl -tag -width 14n +.It Fl b Ar block_addr +Relocate to the given tape block or logical object identifier. +Note that the block number is the Reported Record Number that is relative +to the beginning of the partition (or beginning of tape). +.It Fl e +Relocate to the end of data. +.It Fl f Ar fileno +Relocate to the given file number. +.It Fl p Ar partition +Specify the partition to change to. +.It Fl s Ar setmark +Relocate to the given set mark. +.El +.It Cm comp +Set the drive's compression mode. +The non-numeric values of +.Ar argument +are: +.Pp +.Bl -tag -width 9n -compact +.It off +Turn compression off. +.It on +Turn compression on. +.It none +Same as +.Ar off . +.It enable +Same as +.Ar on . +.It IDRC +IBM Improved Data Recording Capability compression (0x10). +.It DCLZ +DCLZ compression algorithm (0x20). +.El +.Pp +In addition to the above recognized compression keywords, the user can +supply a numeric compression algorithm for the drive to use. +In most +cases, simply turning the compression +.Sq on +will have the desired effect of enabling the default compression algorithm +supported by the drive. +If this is not the case (see the +.Cm status +display to see which compression algorithm is currently in use), the user +can manually specify one of the supported compression keywords (above), or +supply a numeric compression value from the drive's specifications. +.Pp +Note that for some older tape drives (for example the Exabyte 8200 and 8500 +series drives) it is necessary to switch to a different density to tell the +drive to record data in its compressed format. +If the user attempts to turn compression on while the uncompressed density +is selected, the drive will return an error. +This is generally not an issue for modern tape drives. +.It Cm density +Set the density for the drive. +For the density codes, see below. +The density value could be given either numerically, or as a string, +corresponding to the +.Dq Reference +field. +If the string is abbreviated, it will be resolved in the order +shown in the table, and the first matching entry will be used. +If the +given string and the resulting canonical density name do not match +exactly, an informational message is output about what the given +string has been taken for. +.El +.Pp +The initial version of the density table below was taken from the +.Sq Historical sequential access density codes +table (A-1) in Revision 11 of the SCSI-3 Stream Device Commands (SSC) +working draft, dated November 11, 1997. +Subsequent additions have come from a number of sources. +.Pp +The density codes are: +.Bd -literal -offset 2n +0x0 default for device +0xE reserved for ECMA + +Value Width Tracks Density Code Type Reference Note + mm in bpmm bpi +0x01 12.7 (0.5) 9 32 (800) NRZI R X3.22-1983 2 +0x02 12.7 (0.5) 9 63 (1,600) PE R X3.39-1986 2 +0x03 12.7 (0.5) 9 246 (6,250) GCR R X3.54-1986 2 +0x05 6.3 (0.25) 4/9 315 (8,000) GCR C X3.136-1986 1,3 +0x06 12.7 (0.5) 9 126 (3,200) PE R X3.157-1987 2 +0x07 6.3 (0.25) 4 252 (6,400) IMFM C X3.116-1986 1 +0x08 3.81 (0.15) 4 315 (8,000) GCR CS X3.158-1987 1 +0x09 12.7 (0.5) 18 1,491 (37,871) GCR C X3.180 2 +0x0A 12.7 (0.5) 22 262 (6,667) MFM C X3B5/86-199 1 +0x0B 6.3 (0.25) 4 63 (1,600) PE C X3.56-1986 1 +0x0C 12.7 (0.5) 24 500 (12,690) GCR C HI-TC1 1,6 +0x0D 12.7 (0.5) 24 999 (25,380) GCR C HI-TC2 1,6 +0x0F 6.3 (0.25) 15 394 (10,000) GCR C QIC-120 1,6 +0x10 6.3 (0.25) 18 394 (10,000) GCR C QIC-150 1,6 +0x11 6.3 (0.25) 26 630 (16,000) GCR C QIC-320 1,6 +0x12 6.3 (0.25) 30 2,034 (51,667) RLL C QIC-1350 1,6 +0x13 3.81 (0.15) 1 2,400 (61,000) DDS CS X3B5/88-185A 5 +0x14 8.0 (0.315) 1 1,703 (43,245) RLL CS X3.202-1991 5,11 +0x15 8.0 (0.315) 1 1,789 (45,434) RLL CS ECMA TC17 5,12 +0x16 12.7 (0.5) 48 394 (10,000) MFM C X3.193-1990 1 +0x17 12.7 (0.5) 48 1,673 (42,500) MFM C X3B5/91-174 1 +0x18 12.7 (0.5) 112 1,673 (42,500) MFM C X3B5/92-50 1 +0x19 12.7 (0.5) 128 2,460 (62,500) RLL C DLTapeIII 6,7 +0x1A 12.7 (0.5) 128 3,214 (81,633) RLL C DLTapeIV(20) 6,7 +0x1B 12.7 (0.5) 208 3,383 (85,937) RLL C DLTapeIV(35) 6,7 +0x1C 6.3 (0.25) 34 1,654 (42,000) MFM C QIC-385M 1,6 +0x1D 6.3 (0.25) 32 1,512 (38,400) GCR C QIC-410M 1,6 +0x1E 6.3 (0.25) 30 1,385 (36,000) GCR C QIC-1000C 1,6 +0x1F 6.3 (0.25) 30 2,666 (67,733) RLL C QIC-2100C 1,6 +0x20 6.3 (0.25) 144 2,666 (67,733) RLL C QIC-6GB(M) 1,6 +0x21 6.3 (0.25) 144 2,666 (67,733) RLL C QIC-20GB(C) 1,6 +0x22 6.3 (0.25) 42 1,600 (40,640) GCR C QIC-2GB(C) ? +0x23 6.3 (0.25) 38 2,666 (67,733) RLL C QIC-875M ? +0x24 3.81 (0.15) 1 2,400 (61,000) CS DDS-2 5 +0x25 3.81 (0.15) 1 3,816 (97,000) CS DDS-3 5 +0x26 3.81 (0.15) 1 3,816 (97,000) CS DDS-4 5 +0x27 8.0 (0.315) 1 3,056 (77,611) RLL CS Mammoth 5 +0x28 12.7 (0.5) 36 1,491 (37,871) GCR C X3.224 1 +0x29 12.7 (0.5) +0x2A +0x2B 12.7 (0.5) 3 ? ? ? C X3.267 5 +0x40 12.7 (0.5) 384 4,800 (123,952) C LTO-1 +0x41 12.7 (0.5) 208 3,868 (98,250) RLL C DLTapeIV(40) 6,7 +0x42 12.7 (0.5) 512 7,398 (187,909) C LTO-2 +0x44 12.7 (0.5) 704 9,638 (244,805) C LTO-3 +0x46 12.7 (0.5) 896 12,725 (323,215) C LTO-4 +0x47 3.81 (0.25) ? 6,417 (163,000) CS DAT-72 +0x48 12.7 (0.5) 448 5,236 (133,000) PRML C SDLTapeI(110) 6,8,13 +0x49 12.7 (0.5) 448 7,598 (193,000) PRML C SDLTapeI(160) 6,8 +0x4A 12.7 (0.5) 768 ? PRML C T10000A 10 +0x4B 12.7 (0.5) 1152 ? PRML C T10000B 10 +0x4C 12.7 (0.5) 3584 ? PRML C T10000C 10 +0x4D 12.7 (0.5) 4608 ? PRML C T10000D 10 +0x51 12.7 (0.5) 512 11,800 (299,720) C 3592A1 (unencrypted) +0x52 12.7 (0.5) 896 11,800 (299,720) C 3592A2 (unencrypted) +0x53 12.7 (0.5) 1152 13,452 (341,681) C 3592A3 (unencrypted) +0x54 12.7 (0.5) 2560 19,686 (500,024) C 3592A4 (unencrypted) +0x55 12.7 (0.5) 5120 20,670 (525,018) C 3592A5 (unencrypted) +0x56 12.7 (0.5) 7680 20,670 (525,018) C 3592B5 (unencrypted) +0x57 12.7 (0.5) 8704 21,850 (554,990) C 3592A6 (unencrypted) +0x58 12.7 (0.5) 1280 15,142 (384,607) C LTO-5 +0x59 12.7 (0.5)18944 21,850 (554,990) C 3592A7 (unencrypted) +0x5A 12.7 (0.5) 2176 15,142 (384,607) C LTO-6 +0x5C 12.7 (0.5) 3584 19,107 (485,318) C LTO-7 +0x5D 12.7 (0.5) 5376 19,107 (485,318) C LTO-M8 14 +0x5E 12.7 (0.5) 6656 20,669 (524,993) C LTO-8 +0x60 12.7 (0.5) 8960 23,031 (584,987) C LTO-9 +0x62 12.7 (0.5)15104 21,657 (550,088) C LTO-10 15 +0x63 12.7 (0.5)15104 22,441 (570,001) C LTO-10P 15 +0x71 12.7 (0.5) 512 11,800 (299,720) C 3592A1 (encrypted) +0x72 12.7 (0.5) 896 11,800 (299,720) C 3592A2 (encrypted) +0x73 12.7 (0.5) 1152 13,452 (341,681) C 3592A3 (encrypted) +0x74 12.7 (0.5) 2560 19,686 (500,024) C 3592A4 (encrypted) +0x75 12.7 (0.5) 5120 20,670 (525,018) C 3592A5 (encrypted) +0x76 12.7 (0.5) 7680 20,670 (525,018) C 3592B5 (encrypted) +0x77 12.7 (0.5) 8704 21,850 (554,990) C 3592A6 (encrypted) +0x79 12.7 (0.5)18944 21,850 (554,990) C 3592A7 (encrypted) +0x8c 8.0 (0.315) 1 1,789 (45,434) RLL CS EXB-8500c 5,9 +0x90 8.0 (0.315) 1 1,703 (43,245) RLL CS EXB-8200c 5,9 +.Ed +.Bd -literal -offset 2n +Code Description Type Description +---- -------------------------------------- ---- ----------- +NRZI Non return to zero, change on ones R Reel-to-reel +GCR Group code recording C Cartridge +PE Phase encoded CS Cassette +IMFM Inverted modified frequency modulation +MFM Modified frequency modulation +DDS DAT data storage +RLL Run length limited +PRML Partial Response Maximum Likelihood +.Ed +.Bd -literal -offset 2n +NOTES +1. Serial recorded. +2. Parallel recorded. +3. Old format known as QIC-11. +5. Helical scan. +6. This is not an American National Standard. The reference is based + on an industry standard definition of the media format. +7. DLT recording: serially recorded track pairs (DLTapeIII and + DLTapeIV(20)), or track quads (DLTapeIV(35) and DLTapeIV(40)). +8. Super DLT (SDLT) recording: 56 serially recorded logical tracks + with 8 physical tracks each. +9. Vendor-specific Exabyte density code for compressed format. +10. bpi/bpmm values for the Oracle/StorageTek T10000 tape drives are + not listed in the manual. Someone with access to a drive can + supply the necessary values by running 'mt getdensity'. +11. This is Exabyte 8200 uncompressed format. The compressed format + density code is 0x90. +12. This is Exabyte 8500 uncompressed format. The compressed format + density code is 0x8c. +13. This density code (0x48) was also used for DAT-160. +14. Officially known as LTO-8 Type M, abbreviated M8. This is a pristine + LTO-7 cartridge initialized with a higher density format by an LTO-8 + drive. It cannot be read by an LTO-7 drive. Uncompressed capacity + is 9TB, compared to 6TB for LTO-7 and 12TB for LTO-8. +15. LTO-10 Premium cartridges hold 40TB uncompressed vs. 30TB + uncompressed for standard LTO-10 cartridges due to slightly higher + density and stronger, thinner, longer tape. LTO-10 tape drives + are not backward compatible with previous generation LTO tape + cartridges. +.Ed +.Bd -literal -offset 2n +NOTE ON QIC STREAMERS + +The following is a table of Data Cartridge types as used in the 1/4 inch +tape drives such as the Archive Viper 150, Wangtek 5525ES, and Tandberg +TDC4220 tape drives: + +Value Reference Format Cartridge Type Capacity Tracks Length +----- --------- ------ -------------- -------- ------ ------ + +0x05 QIC-11 DC300 15MB 4 300ft +0x05 QIC-11 DC300XL/P 20MB 4 450ft +0x05 QIC-11 DC600 27MB 4 600ft +0x05 X3.136-1986 QIC-24 DC615A 15MB 9 150ft +0x05 X3.136-1986 QIC-24 DC300XL/P 45MB 9 450ft +0x05 X3.136-1986 QIC-24 DC600A 60MB 9 600ft +0x0F QIC-120 QIC-120 DC600A/DC6150 120MB 15 620ft +0x10 QIC-150 QIC-150 DC600XTD/DC6150 150MB 18 620ft +0x10 QIC-150 QIC-150 DC6250 250MB 18 1,020ft +0x11 QIC-320 QIC-525 DC6320 320MB 26 620ft +0x11 QIC-320 QIC-525 DC6525 525MB 26 1,020ft +0x1E QIC-1000C QIC-1000 DC9100/DL9135 1.0GB 30 760ft +0x1E QIC-1000C QIC-1000 DC9150 1.2GB 30 950ft +0x22 QIC-2GB(C) QIC-2GB DC9200 2.0GB 42 950ft +0x22 QIC-2GB(C) QIC-2GB DC9250 2.5GB 42 1,200ft +.Ed +.Pp +Notes: +.Pp +QIC-24, QIC-120, QIC-150 use fixed blocksize of 512 bytes, QIC-525, QIC-1000 +and QIC-2GB can use blocksize of 1,024 bytes. +DDS (DAT) drives generally use variable blocks. +.Pp +QIC-02 and QIC-36 are interface standards for tape drives. +The QIC-02 and QIC-36 streamers such as the Wangtek 5250EQ are otherwise +identical to their SCSI versions (i.e.: Wangtek 5250ES). +.Pp +It seems that the 150MB and larger streamers cannot write QIC-24 9 track +formats, only read them. +.Pp +DC600A cartridges marked "10,000ftpi" can only be used as QIC-11, QIC-24, +and QIC-120 format. +DC600A cartridges marked 12,500ftpi can be used as both QIC-120 and QIC-150 +format. +.Pp +Some manufacturers do not use "DC" on their cartridges. +Verbatim uses DL, Maxell uses MC, Sony uses QD, Quill uses DQ. +.Pp +3M/Imation & Fuji use DC. +Thus a DL6250, MC-6250, QD6250, DQ6250 are all identical media to a DC6250. +.Pp +QIC tape media is not "connected" to the take up reels and will de-spool +if the tape drive has dust covering the light sensor that looks for the end +of tape holes in the media. +.Sh ENVIRONMENT +.Bl -tag -width ".Ev TAPE" +.It Ev TAPE +This is the pathname of the tape drive. +The default (if the variable is unset, but not if it is null) is +.Pa /dev/nsa0 . +It may be overridden with the +.Fl f +option. +.El +.Sh FILES +.Bl -tag -width ".Pa /dev/*sa[0-9]*" -compact +.It Pa /dev/*sa[0-9]* +SCSI magnetic tape interface +.El +.Sh DIAGNOSTICS +The exit status will be 0 when the drive operations were successful, +2 when the drive operations were unsuccessful, and 1 for other +problems like an unrecognized command or a missing drive device. +.Sh COMPATIBILITY +Some undocumented commands support old software. +.Sh SEE ALSO +.Xr dd 1 , +.Xr ioctl 2 , +.Xr mtio 4 , +.Xr sa 4 , +.Xr environ 7 +.Sh HISTORY +The +.Nm +command appeared in +.Bx 4.3 . +.Pp +Extensions regarding the +.Xr st 4 +driver appeared in +.Bx 386 0.1 +as a separate +.Nm st +command, and have been merged into the +.Nm +command in +.Fx 2.1 . +.Pp +The former +.Cm eof +command that used to be a synonym for +.Cm weof +has been abandoned in +.Fx 2.1 +since it was often confused with +.Cm eom , +which is fairly dangerous. +.Sh BUGS +The utility cannot be interrupted or killed during a long erase +(which can be longer than an hour), and it is easy to forget +that the default erase is long. +.Pp +Hardware block numbers do not always correspond to blocks on the tape +when the drive uses internal compression. +.Pp +Erasure is not guaranteed if the tape is not at its beginning. +.Pp +Tape-related documentation is poor, here and elsewhere. |