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DISKTAB(5)		  FreeBSD 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 patterned	after the termcap(5) terminal data-
     base.  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 en-
     try:

     Name      Type    Description
     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.
     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).
     [...]
     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
     getdiskbyname(3), disklabel(5), disklabel(8), newfs(8)

HISTORY
     The disktab description file appeared in 4.2BSD.

FreeBSD	13.0		      September	20, 2018		  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | FILES | SEE ALSO | HISTORY

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=disktab&sektion=5&manpath=OpenBSD+6.9>

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