.\" Copyright (c) 1983, 1991, 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
.\" 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. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. 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
.\" @(#)mtio.4 8.1 (Berkeley) 6/5/93
These devices are typical tape block devices,
The following table of the converntional device names
is applicable to any of the transport/controller pairs.
.Bl -column "no-rewindxxx" "or lowest densityxx" "or lowest densityxx" "or lowest densityxx" -offset indent
800 BPI 1600 BPI 6500 BPI
.Em or lowest density or second density or third density
Rewind mt0/rmt0 mt8/rmt8 mt16/rmt16
Rewind mt1/rmt1 mt9/rmt9 mt17/rmt17
Rewind mt2/rmt2 mt10/rmt10 mt18/rmt18
Rewind mt3/rmt3 mt11/rmt11 mt19/rmt19
No-rewind nmt4/nrmt4 nmt12/nrmt12 nmt20/nrmt20
No-rewind nmt5/nrmt5 nmt13/nrmt13 nmt21/nrmt21
No-rewind nmt6/nrmt6 nmt14/nrmt14 nmt22/nrmt22
No-rewind nmt7/nrmt7 nmt15/nrmt15 nmt23/nrmt32
The rewind devices automatically rewind
when the last requested read, write or seek has finished, or the end of the tape
has been reached. The letter
the name of the no-rewind devices.
Unix tapes are written in multiples of 1024 byte block
records. Two end-of-file markers mark the end of a tape, and
one end-of-file marker marks the end of a tape file.
If the tape is not to be rewound it is positioned with the
head in between the two tape marks, where the next write
will over write the second end-of-file marker.
All of the magtape devices may be manipulated with the
The following definitions are from
* Structures and definitions for mag tape io control commands
/* structure for MTIOCTOP - mag tape op command */
short mt_op; /* operations defined below */
daddr_t mt_count; /* how many of them */
#define MTWEOF 0 /* write an end-of-file record */
#define MTFSF 1 /* forward space file */
#define MTBSF 2 /* backward space file */
#define MTFSR 3 /* forward space record */
#define MTBSR 4 /* backward space record */
#define MTREW 5 /* rewind */
#define MTOFFL 6 /* rewind and put the drive offline */
#define MTNOP 7 /* no operation, sets status only */
#define MTCACHE 8 /* enable controller cache */
#define MTNOCACHE 9 /* disable controller cache */
/* structure for MTIOCGET - mag tape get status command */
short mt_type; /* type of magtape device */
/* the following two registers are grossly device dependent */
short mt_dsreg; /* ``drive status'' register */
short mt_erreg; /* ``error'' register */
/* end device-dependent registers */
short mt_resid; /* residual count */
/* the following two are not yet implemented */
daddr_t mt_fileno; /* file number of current position */
daddr_t mt_blkno; /* block number of current position */
/* end not yet implemented */
* Constants for mt_type byte. These are the same
* for controllers compatible with the types listed.
#define MT_ISTS 0x01 /* TS-11 */
#define MT_ISHT 0x02 /* TM03 Massbus: TE16, TU45, TU77 */
#define MT_ISTM 0x03 /* TM11/TE10 Unibus */
#define MT_ISMT 0x04 /* TM78/TU78 Massbus */
#define MT_ISUT 0x05 /* SI TU-45 emulation on Unibus */
#define MT_ISCPC 0x06 /* SUN */
#define MT_ISAR 0x07 /* SUN */
#define MT_ISTMSCP 0x08 /* DEC TMSCP protocol (TU81, TK50) */
#define MT_ISCY 0x09 /* CCI Cipher */
#define MT_ISCT 0x0a /* HP 1/4 tape */
#define MT_ISFHP 0x0b /* HP 7980 1/2 tape */
#define MT_ISEXABYTE 0x0c /* Exabyte */
#define MT_ISEXA8200 0x0c /* Exabyte EXB-8200 */
#define MT_ISEXA8500 0x0d /* Exabyte EXB-8500 */
#define MT_ISVIPER1 0x0e /* Archive Viper-150 */
#define MT_ISPYTHON 0x0f /* Archive Python (DAT) */
#define MT_ISHPDAT 0x10 /* HP 35450A DAT drive */
/* mag tape io control commands */
#define MTIOCTOP _IOW('m', 1, struct mtop) /* do a mag tape op */
#define MTIOCGET _IOR('m', 2, struct mtget) /* get tape status */
#define MTIOCIEOT _IO('m', 3) /* ignore EOT error */
#define MTIOCEEOT _IO('m', 4) /* enable EOT error */
#define DEFTAPE "/dev/rmt12"
#define T_UNIT 003 /* unit selection */
#define T_NOREWIND 004 /* no rewind on close */
#define T_DENSEL 030 /* density select */
#define T_800BPI 000 /* select 800 bpi */
#define T_1600BPI 010 /* select 1600 bpi */
#define T_6250BPI 020 /* select 6250 bpi */
#define T_BADBPI 030 /* undefined selection */
.Bl -tag -width /dev/rmt? -compact
The status should be returned in a device independent format.
The special file naming should be redone in a more consistent and
projects / unix-history / blob