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.