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 patterned after the
termcap(5) terminal database. Entries in
disktab 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 “|” 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 (default: ns*nt). |
| su | num | Number of sectors per unit (default: sc*nc). |
| se | num | Sector size in bytes (default: DEV_BSIZE). |
| sf | bool | Controller supports bad144-style bad sector forwarding. |
| rm | num | Rotation speed in RPM (default: 3600). |
| sk | num | Sector skew per track (default: 0). |
| cs | num | Sector skew per cylinder (default: 0). |
| hs | num | Headswitch time in usec (default: 0). |
| ts | num | One-cylinder seek time in usec (default: 0). |
| il | num | Sector interleave (n:1) (default: 1). |
| d[0-4] | num | Drive-type-dependent parameters. |
| b0 | str | Pathname to primary bootstrap. |
| b1 | str | Pathname to secondary bootstrap. |
| 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). |
| [...] | ||
| bp | num | Block size for partition “p” (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). |
| [...] | ||
| fp | num | Fragment size for partition “p” (bytes). |
| oa | num | Offset of partition “a” (sectors). |
| ob | num | Offset of partition “b” (sectors). |
| oc | num | Offset of partition “c” (sectors). |
| [...] | ||
| op | num | Offset of partition “p” (sectors). |
| pa | num | Size of partition “a” (sectors). |
| pb | num | Size of partition “b” (sectors). |
| pc | num | Size of partition “c” (sectors). |
| [...] | ||
| pp | num | Size of partition “p” (sectors). |
| ta | str | Type of partition “a” (4.2BSD, swap, etc.). |
| tb | str | Type of partition “b”. |
| tc | str | Type of partition “c”. |
| [...] | ||
| tp | str | Type of partition “p”. |
FILES
- /etc/disktab
SEE ALSO
HISTORY
The disktab description file appeared in
4.2BSD.