xref: /openbsd-src/share/man/man5/disktab.5 (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1.\"	$OpenBSD: disktab.5,v 1.12 2007/05/31 19:19:58 jmc Exp $
2.\"	$NetBSD: disktab.5,v 1.4 1994/11/30 19:31:15 jtc Exp $
3.\"
4.\" Copyright (c) 1983, 1991, 1993
5.\"	The Regents of the University of California.  All rights reserved.
6.\"
7.\" Redistribution and use in source and binary forms, with or without
8.\" modification, are permitted provided that the following conditions
9.\" are met:
10.\" 1. Redistributions of source code must retain the above copyright
11.\"    notice, this list of conditions and the following disclaimer.
12.\" 2. Redistributions in binary form must reproduce the above copyright
13.\"    notice, this list of conditions and the following disclaimer in the
14.\"    documentation and/or other materials provided with the distribution.
15.\" 3. Neither the name of the University nor the names of its contributors
16.\"    may be used to endorse or promote products derived from this software
17.\"    without specific prior written permission.
18.\"
19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29.\" SUCH DAMAGE.
30.\"
31.\"     @(#)disktab.5	8.1 (Berkeley) 6/5/93
32.\"
33.Dd $Mdocdate: May 31 2007 $
34.Dt DISKTAB 5
35.Os
36.Sh NAME
37.Nm disktab
38.Nd disk description file
39.Sh SYNOPSIS
40.Fd #include <disktab.h>
41.Sh DESCRIPTION
42.Nm
43is a simple database which describes disk geometries and
44disk partition characteristics.
45It is used
46.\"by the formatter(\c
47.\"IR.Xr format 8 )
48.\"to determine how to format the disk, and
49to initialize the disk label on the disk.
50The format is patterned after the
51.Xr termcap 5
52terminal database.
53Entries in
54.Nm
55consist of a number of colon
56.Pq Ql \&:
57separated fields.
58The first entry for each disk gives the names which are
59known for the disk, separated by
60.Dq \&|
61characters.
62The last name given should be a long name fully identifying the disk.
63.Pp
64The following list indicates the normal values stored for each disk entry:
65.Bl -column "indent" "boolx"
66.It Sy Name	Type	Description
67.It "\&ty	str	Type of disk (e.g., removable, winchester)."
68.It "\&dt	str	Type of controller (e.g.,"
69.Tn SMD , ESDI ,
70floppy).
71.It "\&ns	num	Number of sectors per track."
72.It "\&nt	num	Number of tracks per cylinder."
73.It "\&nc	num	Total number of cylinders on the disk."
74.It "\&sc	num	Number of sectors per cylinder (default: ns*nt)."
75.It "\&su	num	Number of sectors per unit (default: sc*nc)."
76.It "\&se	num	Sector size in bytes (default:"
77.Dv DEV_BSIZE ) .
78.It "\&sf	bool	Controller supports bad144-style bad sector forwarding."
79.It "\&rm	num	Rotation speed in RPM (default: 3600)."
80.It "\&sk	num	Sector skew per track (default: 0)."
81.It "\&cs	num	Sector skew per cylinder (default: 0)."
82.It "\&hs	num	Headswitch time in usec (default: 0)."
83.It "\&ts	num	One-cylinder seek time in usec (default: 0)."
84.It "\&il	num	Sector interleave (n:1) (default: 1)."
85.It "\&d[0-4]	num	Drive-type-dependent parameters."
86.It "\&b0	str	Pathname to primary bootstrap."
87.It "\&b1	str	Pathname to secondary bootstrap."
88.It "\&bs	num	Boot block size (default:"
89.Dv BBSIZE ) .
90.It "\&sb	num	Superblock size (default: "
91.Dv SBSIZE ) .
92.Pp
93.It "\&ba	num	Block size for partition"
94.Dq a
95(bytes).
96.It "\&bd	num	Block size for partition"
97.Dq d
98(bytes).
99.It "\&be	num	Block size for partition"
100.Dq e
101(bytes).
102.It [...]
103.It "\&bp	num	Block size for partition"
104.Dq p
105(bytes).
106.Pp
107.It "\&fa	num	Fragment size for partition"
108.Dq a
109(bytes).
110.It "\&fd	num	Fragment size for partition"
111.Dq d
112(bytes).
113.It "\&fe	num	Fragment size for partition"
114.Dq e
115(bytes).
116.It [...]
117.It "\&fp	num	Fragment size for partition"
118.Dq p
119(bytes).
120.Pp
121.It "\&oa	num	Offset of partition"
122.Dq a
123(sectors).
124.It "\&ob	num	Offset of partition"
125.Dq b
126(sectors).
127.It "\&oc	num	Offset of partition"
128.Dq c
129(sectors).
130.It [...]
131.It "\&op	num	Offset of partition"
132.Dq p
133(sectors).
134.Pp
135.It "\&pa	num	Size of partition"
136.Dq a
137(sectors).
138.It "\&pb	num	Size of partition"
139.Dq b
140(sectors).
141.It "\&pc	num	Size of partition"
142.Dq c
143(sectors).
144.It [...]
145.It "\&pp	num	Size of partition"
146.Dq p
147(sectors).
148.Pp
149.It "\&ta	str	Type of partition"
150.Dq a
151(4.2BSD, swap, etc.).
152.It "\&tb	str	Type of partition"
153.Dq b .
154.It "\&tc	str	Type of partition"
155.Dq c .
156.It [...]
157.It "\&tp	str	Type of partition"
158.Dq p .
159.El
160.Sh FILES
161.Bl -tag -width /etc/disktab -compact
162.It Pa /etc/disktab
163.El
164.Sh SEE ALSO
165.Xr getdiskbyname 3 ,
166.Xr disklabel 5 ,
167.Xr disklabel 8 ,
168.Xr newfs 8
169.Sh HISTORY
170The
171.Nm
172description file appeared in
173.Bx 4.2 .
174