Content-type: text/html
disktab - Disk description file
#include <sys/disklabel.h>
The disktab database describes disk geometries and disk partition characteristics. It is used to initialize the disk label on the disk. The format is patterned after the termcap terminal database. Entries in a disktab file consist of a number of : (colon) separated fields. The first entry for each disk gives the names which are known for the disk, separated by | (vertical bar) 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:
Type Description
str Type of disk (for example, removable, winchester)
str Type of controller (for example, SMD, ESDI,
floppy)
num Number of sectors per track
num Number of tracks per cylinder
num Total number of cylinders on the disk
num Number of sectors per cylinder, nc*nt default
num Number of sectors per unit, sc*nc default
num Sector size in bytes, DEV_BSIZE default
bool Controller supports bad144-style bad sector
forwarding
num Rotation speed, rpm, default 3600
num Sector skew per track, default 0
num Sector skew per cylinder, default 0
num Headswitch time, usec, default 0
num One-cylinder seek time, usec, default 0
num Sector interleave (n:1), default 1
num Drive-type-dependent parameters
num Boot block size, default BBSIZE
num Superblock size, default SBSIZE
num Block size for partition `a' (bytes)
num Block size for partition `d' (bytes)
num Block size for partition `e' (bytes)
num Block size for partition `f' (bytes)
num Block size for partition `g' (bytes)
num Block size for partition `h' (bytes)
num Fragment size for partition `a' (bytes)
num Fragment size for partition `d' (bytes)
num Fragment size for partition `e' (bytes)
num Fragment size for partition `f' (bytes)
num Fragment size for partition `g' (bytes)
num Fragment size for partition `h' (bytes)
num Offset of partition `a' in sectors
num Offset of partition `b' in sectors
num Offset of partition `c' in sectors
num Offset of partition `d' in sectors
num Offset of partition `e' in sectors
num Offset of partition `f' in sectors
num Offset of partition `g' in sectors
num Offset of partition `h' in sectors
num Size of partition `a' in sectors
num Size of partition `b' in sectors
num Size of partition `c' in sectors
num Size of partition `d' in sectors
num Size of partition `e' in sectors
num Size of partition `f' in sectors
num Size of partition `g' in sectors
num Size of partition `h' in sectors
str Partition type of partition `a' (4.2BSD file system,
swap, etc.)
str Partition type of partition `b'
str Partition type of partition `c'
str Partition type of partition `d'
str Partition type of partition `e'
str Partition type of partition `f'
str Partition type of partition `g'
str Partition type of partition `h'
The following is an example disktab entry:
rz25|RZ25|DEC RZ25 Winchester:\
:ty=winchester:dt=SCSI:ns#62:nt#9:nc#1492:\
:oa#0:pa#131072:ba#8192:fa#1024:\
:ob#131072:pb#262144:bb#8192:fb#1024:\
:oc#0:pc#832527:bc#8192:fc#1024:\
:od#393216:pd#146437:bd#8192:fd#1024:\
:oe#539656:pe#146437:be#8192:fe#1024:\
:of#686096:pf#146437:bf#8192:ff#1024:\
:og#393216:pg#439311:bg#8192:fg#1024:\
:oh#0:ph#0:bh#8192:fh#1024:
Functions: getdiskbyname(3)
Files: disklabel(4)
Commands: disklabel(8), newfs(8) delim off