1.\" Copyright (c) 1983, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" from: @(#)mtio.4 6.5 (Berkeley) 3/27/91 33.\" $Id: mtio.4,v 1.2 1993/08/01 07:36:07 mycroft Exp $ 34.\" 35.Dd March 27, 1991 36.Dt MTIO 4 vax 37.Os BSD 4.2 38.Sh NAME 39.Nm mtio 40.Nd 41.Tn UNIX 42magtape interface 43.Sh DESCRIPTION 44The special files 45named 46.Pa /dev/mt0 47and 48.Pa /dev/rmt0 49through 50.Pa /dev/mt23 51and 52.Pa /dev/rmt23 53refer to 54.Tn UNIX 55magtape drives, 56which may be on the 57.Tn MASSBUS 58using the 59.Tn TM03 60formatter 61.Xr ht 4 , 62or 63.Tn TM78 64formatter, 65.Xr mt 4 , 66or on the 67.Tn UNIBUS 68using either the 69.Tn TM11 70or 71.Tn TS11 72formatters 73.Xr tm 4 , 74.Tn TU45 75compatible formatters, 76.Xr ut 4 , 77or 78.Xr ts 4 . 79These devices are typical tape block devices, 80see 81.Xr physio 4 . 82.Pp 83The following table of the converntional device names 84is applicable to any of the transport/controller pairs. 85(But note that only 1600 86.Tn BPI 87is available with the 88.Tn TS11 . ) 89.Bl -column "no-rewindxxx" "or lowest densityxx" "or lowest densityxx" "or lowest densityxx" -offset indent 90 800 BPI 1600 BPI 6500 BPI 91.Em or lowest density or second density or third density 92 93Rewind mt0/rmt0 mt8/rmt8 mt16/rmt16 94Rewind mt1/rmt1 mt9/rmt9 mt17/rmt17 95Rewind mt2/rmt2 mt10/rmt10 mt18/rmt18 96Rewind mt3/rmt3 mt11/rmt11 mt19/rmt19 97No-rewind nmt4/nrmt4 nmt12/nrmt12 nmt20/nrmt20 98No-rewind nmt5/nrmt5 nmt13/nrmt13 nmt21/nrmt21 99No-rewind nmt6/nrmt6 nmt14/nrmt14 nmt22/nrmt22 100No-rewind nmt7/nrmt7 nmt15/nrmt15 nmt23/nrmt32 101.El 102.Pp 103The rewind devices automatically rewind 104when the last requested read, write or seek has finished, or the end of the tape 105has been reached. The letter 106.Ql n 107is usually prepended to 108the name of the no-rewind devices. 109.Pp 110Unix tapes are written in multiples of 1024 byte block 111records. Two end-of-file markers mark the end of a tape, and 112one end-of-file marker marks the end of a tape file. 113If the tape is not to be rewound it is positioned with the 114head in between the two tape marks, where the next write 115will over write the second end-of-file marker. 116.Pp 117All of the magtape devices may be manipulated with the 118.Xr mt 1 119command. 120.Pp 121A number of 122.Xr ioctl 2 123operations are available 124on raw magnetic tape. 125The following definitions are from 126.Aq Pa sys/mtio.h : 127.Bd -literal 128/* 129 * Structures and definitions for mag tape io control commands 130 */ 131 132/* structure for MTIOCTOP - mag tape op command */ 133struct mtop { 134 short mt_op; /* operations defined below */ 135 daddr_t mt_count; /* how many of them */ 136}; 137 138/* operations */ 139#define MTWEOF 0 /* write an end-of-file record */ 140#define MTFSF 1 /* forward space file */ 141#define MTBSF 2 /* backward space file */ 142#define MTFSR 3 /* forward space record */ 143#define MTBSR 4 /* backward space record */ 144#define MTREW 5 /* rewind */ 145#define MTOFFL 6 /* rewind and put the drive offline */ 146#define MTNOP 7 /* no operation, sets status only */ 147#define MTCACHE 8 /* enable controller cache */ 148#define MTNOCACHE 9 /* disable controller cache */ 149 150/* structure for MTIOCGET - mag tape get status command */ 151 152struct mtget { 153 short mt_type; /* type of magtape device */ 154/* the following two registers are grossly device dependent */ 155 short mt_dsreg; /* ``drive status'' register */ 156 short mt_erreg; /* ``error'' register */ 157/* end device-dependent registers */ 158 short mt_resid; /* residual count */ 159/* the following two are not yet implemented */ 160 daddr_t mt_fileno; /* file number of current position */ 161 daddr_t mt_blkno; /* block number of current position */ 162/* end not yet implemented */ 163}; 164 165/* 166 * Constants for mt_type byte. These are the same 167 * for controllers compatible with the types listed. 168 */ 169#define MT_ISTS 0x01 /* TS-11 */ 170#define MT_ISHT 0x02 /* TM03 Massbus: TE16, TU45, TU77 */ 171#define MT_ISTM 0x03 /* TM11/TE10 Unibus */ 172#define MT_ISMT 0x04 /* TM78/TU78 Massbus */ 173#define MT_ISUT 0x05 /* SI TU-45 emulation on Unibus */ 174#define MT_ISCPC 0x06 /* SUN */ 175#define MT_ISAR 0x07 /* SUN */ 176#define MT_ISTMSCP 0x08 /* DEC TMSCP protocol (TU81, TK50) */ 177#define MT_ISCY 0x09 /* CCI Cipher */ 178#define MT_ISCT 0x0a /* HP 1/4 tape */ 179#define MT_ISFHP 0x0b /* HP 7980 1/2 tape */ 180#define MT_ISEXABYTE 0x0c /* Exabyte */ 181#define MT_ISEXA8200 0x0c /* Exabyte EXB-8200 */ 182#define MT_ISEXA8500 0x0d /* Exabyte EXB-8500 */ 183#define MT_ISVIPER1 0x0e /* Archive Viper-150 */ 184#define MT_ISPYTHON 0x0f /* Archive Python (DAT) */ 185#define MT_ISHPDAT 0x10 /* HP 35450A DAT drive */ 186 187/* mag tape io control commands */ 188#define MTIOCTOP _IOW('m', 1, struct mtop) /* do a mag tape op */ 189#define MTIOCGET _IOR('m', 2, struct mtget) /* get tape status */ 190#define MTIOCIEOT _IO('m', 3) /* ignore EOT error */ 191#define MTIOCEEOT _IO('m', 4) /* enable EOT error */ 192 193#ifndef KERNEL 194#define DEFTAPE "/dev/rmt12" 195#endif 196 197#ifdef KERNEL 198/* 199 * minor device number 200 */ 201 202#define T_UNIT 003 /* unit selection */ 203#define T_NOREWIND 004 /* no rewind on close */ 204#define T_DENSEL 030 /* density select */ 205#define T_800BPI 000 /* select 800 bpi */ 206#define T_1600BPI 010 /* select 1600 bpi */ 207#define T_6250BPI 020 /* select 6250 bpi */ 208#define T_BADBPI 030 /* undefined selection */ 209#endif 210.Ed 211.Pp 212.Sh FILES 213.Bl -tag -width /dev/rmt? -compact 214.It Pa /dev/mt? 215.It Pa /dev/rmt? 216.El 217.Sh SEE ALSO 218.Xr mt 1 , 219.Xr tar 1 , 220.Xr tp 1 , 221.Xr ht 4 , 222.Xr tm 4 , 223.Xr ts 4 , 224.Xr mt 4 , 225.Xr ut 4 226.Sh HISTORY 227The 228.Nm mtio 229manual appeared in 230.Bx 4.2 . 231.Sh BUGS 232The status should be returned in a device independent format. 233.Pp 234The special file naming should be redone in a more consistent and 235understandable manner. 236