OSF

NAME

disktab − Disk description file

SYNOPSIS

#include <disktab.h>

DESCRIPTION

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:

NameTypeDescription

tystrType of disk (e.g. removable, winchester)

dtstrType of controller (e.g. SMD, ESDI, floppy)

nsnumNumber of sectors per track

ntnumNumber of tracks per cylinder

ncnumTotal number of cylinders on the disk

scnumNumber of sectors per cylinder, nc∗nt default

sunumNumber of sectors per unit, sc∗nc default

senumSector size in bytes, DEV_BSIZE default

sfboolController supports bad144-style bad sector forwarding

rmnumRotation speed, rpm, default 3600

sknumSector skew per track, default 0

csnumSector skew per cylinder, default 0

hsnumHeadswitch time, usec, default 0

tsnumOne-cylinder seek time, usec, default 0

ilnumSector interleave (n:1), default 1

d[0-4]numDrive-type-dependent parameters

bsnumBoot block size, default BBSIZE

sbnumSuperblock size, default SBSIZE

banumBlock size for partition ‘a’ (bytes)

bdnumBlock size for partition ‘d’ (bytes)

benumBlock size for partition ‘e’ (bytes)

bfnumBlock size for partition ‘f’ (bytes)

bgnumBlock size for partition ‘g’ (bytes)

bhnumBlock size for partition ‘h’ (bytes)

fanumFragment size for partition ‘a’ (bytes)

fdnumFragment size for partition ‘d’ (bytes)

fenumFragment size for partition ‘e’ (bytes)

ffnumFragment size for partition ‘f’ (bytes)

fgnumFragment size for partition ‘g’ (bytes)

fhnumFragment size for partition ‘h’ (bytes)

oanumOffset of partition ‘a’ in sectors

obnumOffset of partition ‘b’ in sectors

ocnumOffset of partition ‘c’ in sectors

odnumOffset of partition ‘d’ in sectors

oenumOffset of partition ‘e’ in sectors

ofnumOffset of partition ‘f’ in sectors

ognumOffset of partition ‘g’ in sectors

ohnumOffset of partition ‘h’ in sectors

panumSize of partition ‘a’ in sectors

pbnumSize of partition ‘b’ in sectors

pcnumSize of partition ‘c’ in sectors

pdnumSize of partition ‘d’ in sectors

penumSize of partition ‘e’ in sectors

pfnumSize of partition ‘f’ in sectors

pgnumSize of partition ‘g’ in sectors

phnumSize of partition ‘h’ in sectors

tastrPartition type of partition ‘a’ (4.2BSD file system, swap, etc.) 

tbstrPartition type of partition ‘b’

tcstrPartition type of partition ‘c’

tdstrPartition type of partition ‘d’

testrPartition type of partition ‘e’

tfstrPartition type of partition ‘f’

tgstrPartition type of partition ‘g’

thstrPartition type of partition ‘h’

EXAMPLE

The following is an example disktab entry:

rz22|RZ22|DEC RZ22 Winchester:\
        :ty=winchester:dt=SCSI:ns#33:nt#4:nc#776:\
        :pa#32768:ba#8192:fa#1024:\
        :pb#69664:bb#8192:fb#1024:\
        :pc#102432:bc#8192:fc#1024:

FILES

/etc/disktab

RELATED INFORMATION

Functions: getdiskbyname(3)

Files: disklabel(4)

Commands: disklabel(8), newfs(8)