DISKTAB(5) | File Formats Manual | DISKTAB(5)

# NAME

`disktab` — disk description file

# SYNOPSIS

`#include <disktab.h>`

# DESCRIPTION

`disktab` is a simple database which describes disk geometries and disk partition characteristics. It is used to initialize the disk label on the disk. The format is described in capfile(5). Entries in `disktab` consist of a number of `:' separated fields. The first entry for each disk gives the names which are known for the disk, separated by `|' characters. The last name given should be a long name fully identifying the disk.

The following list indicates the normal values stored for each disk entry.

Name | Type | Description
ty | str | Type of disk (e.g. removable, winchester)
dt | str | Type of controller (e.g. SMD, ESDI, floppy)
ns | num | Number of sectors per track
nt | num | Number of tracks per cylinder
nc | num | Total number of cylinders on the disk
sc | num | Number of sectors per cylinder, ns*nt default
su | num | Number of sectors per unit, sc*nc default
se | num | Sector size in bytes, `DEV_BSIZE` default
sf | bool | Controller supports bad144-style bad sector forwarding
rm | num | Rotation speed, rpm, 3600 default
sk | num | Sector skew per track, default 0
cs | num | Sector skew per cylinder, default 0
hs | num | Headswitch time, usec, default 0
ts | num | One-cylinder seek time, usec, default 0
il | num | Sector interleave (n:1), 1 default
d[0-4] | num | Drive-type-dependent parameters
bs | num | Boot block size, default `BBSIZE`
sb | num | Superblock size, default `SBSIZE`
ba | num | Block size for partition `a' (bytes)
bd | num | Block size for partition `d' (bytes)
be | num | Block size for partition `e' (bytes)
bf | num | Block size for partition `f' (bytes)
bg | num | Block size for partition `g' (bytes)
bh | num | Block size for partition `h' (bytes)
fa | num | Fragment size for partition `a' (bytes)
fd | num | Fragment size for partition `d' (bytes)
fe | num | Fragment size for partition `e' (bytes)
ff | num | Fragment size for partition `f' (bytes)
fg | num | Fragment size for partition `g' (bytes)
fh | num | Fragment size for partition `h' (bytes)
oa | num | Offset of partition `a' in sectors
ob | num | Offset of partition `b' in sectors
oc | num | Offset of partition `c' in sectors
od | num | Offset of partition `d' in sectors
oe | num | Offset of partition `e' in sectors
of | num | Offset of partition `f' in sectors
og | num | Offset of partition `g' in sectors
oh | num | Offset of partition `h' in sectors
pa | num | Size of partition `a' in sectors
pb | num | Size of partition `b' in sectors
pc | num | Size of partition `c' in sectors
pd | num | Size of partition `d' in sectors
pe | num | Size of partition `e' in sectors
pf | num | Size of partition `f' in sectors
pg | num | Size of partition `g' in sectors
ph | num | Size of partition `h' in sectors
ta | str | Partition type of partition `a' (4.2BSD filesystem, swap, etc)
tb | str | Partition type of partition `b'
tc | str | Partition type of partition `c'
td | str | Partition type of partition `d'
te | str | Partition type of partition `e'
tf | str | Partition type of partition `f'
tg | str | Partition type of partition `g'
th | str | Partition type of partition `h'

# FILES

/etc/disktab

# SEE ALSO

getdiskbyname(3), capfile(5), disklabel(5), disklabel(8), newfs(8)

# HISTORY

The `disktab` description file appeared in 4.2BSD.

April 5, 2012 | NetBSD 10.99