Langue: en

Version: 20 January 2006 (fedora - 06/07/09)

Section: 5 (Format de fichier)


libdskrc - Custom format definitions for LibDSK programs


The libdskrc file contains definitions of disk geometries, which can be used by the LibDsk utilities dsktrans(1) , dskid(1) and dskform(1)

The file consists of one or more sections, each describing one disk layout. Each section begins with the format name in square brackets, and continues until the next section begins. Within each section are one or more entries of the form

variable = value

Anything after a semicolon or hash character is treated as a comment and ignored. Blank lines are also ignored.


For each geometry, the entries listed below can be present. If not all the values are present, LibDsk will use default values from its "pcw180" format (40 tracks, 9 sectors, single-sided, MFM).

description = DESC
The description of the format as shown by (for example) dskform --help.
How a double-sided disk is handled. This can either be alt (sides alternate -- used by most PC-hosted operating systems), outback (use side 0 tracks 0-79, then side 1 tracks 79-0 -- used by 144FEAT CP/M disks), or outout (use side 0 tracks 0-79, then side 1 tracks 0-79 -- used by some Acorn formats). If the disk is single-sided, this parameter can be omitted.
cylinders = COUNT
Sets the number of cylinders (usually 40 or 80).
heads = COUNT
Sets the number of heads (usually 1 or 2 for single- or double-sided).
sectors = COUNT
Sets the number of sectors per track.
secbase = NUMBER
Sets the first sector number on a track. Usually 1; some Acorn formats use 0.
secsize = COUNT
Sets the size of a sector in bytes. This should be a power of 2.
datarate = VALUE
Sets the rate at which the disk should be accessed. This is one of HD (1.4Mb or 1.2Mb), DD (360k or 720k disc in 1.2Mb drive), SD (360k or 720k disc in 1.4Mb, 720k or 360k drive), ED (2.8Mb).
rwgap = VALUE
Set the read/write gap.
fmtgap = VALUE
Set the format gap.
fm = Y or N
Set the recording mode. Y for FM, N for MFM.
multitrack = Y or N
Set multitrack mode; this only affects attempts to read normal data from tracks containing deleted data (or vice versa). Y for yes, N for no.
skipdeleted = Y or N
Skip deleted data when searching for non-deleted data (or vice versa). Y for yes, N for no.


User-specified format list.
System-wide format list.


dsktrans(1) , dskform(1) , dskid(1)


John Elliott <>.