Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
dskutil(1)			    Emulators			      dskutil(1)

NAME
     dskutil - Simple sector edtor for discs and disc images.

SYNOPSIS
     dskutil  [-type  TYPE]  [-side  SIDE]  [-comp COMP] [-dstep] [-retry COUNT]
     [-format FMT] DISKIMAGE

DESCRIPTION
     dskutil is an interactive command-driven sector editor, patterned after the
     venerable CP/M sector editor DU90. This explains some  of	its  idiosyncra-
     cies,  such  as  the  fact  that commands deal in logical track numbers but
     physical sector numbers.

OPTIONS
     -type TYPE
	    Determines which LibDsk driver is to be used to access the disc.

	    auto    Select according to the disc image file.  This  is	the  de-
		    fault.

	    dsk     Use the DSK (CPCEmu format) image driver.

	    edsk    Use the extended version of the DSK format.

	    floppy  Use the floppy driver.

	    myz80   Use the hard disk (MYZ80 format) image driver.  (This format
		    cannot be autodetected.)

	    cfi     Use  the CFI (DOS fdcopy format) image driver.  (This format
		    cannot be autodetected.)

	    apridisk
		    Use the ApriDisk image driver (from the utility of the  same
		    name).  (This format cannot be autodetected.)

	    raw     Use the raw driver.

     -comp COMP
	    Select  the  compression  method used on the disc image file (has no
	    effect when reading a floppy disc).

	    auto    Detect from the first few bytes of the file. This is the de-
		    fault.

	    sq	    Huffman coded (SQ / USQ).

	    gz	    Gzipped (gzip / gunzip).

	    bz2     Burrows-Wheeler compressed (bzip2 / bunzip2).

     -side SIDE
	    Determines which side (0 or 1) of the source disc is to be	scanned.
	    If this option is not present both sides will be scanned.

     -dstep
	    Double-step  the source drive (used to read 360k discs in 1.2Mb dri-
	    ves). Only supported by the Linux floppy driver.

     -retry COUNT
	    Set the number of times to attempt a read/write/format  in	case  of
	    error.

     -format FMT
	    Do	not autodetect the disc format; use the named format. The format
	    need only be an approximation to the actual format used by the disc.

     -first CYL
	    Start scanning at the specified cylinder.

     -last CYL
	    Scan up to and including the specified cylinder.

COMMANDS
     The following single-letter commands are used. Operands in brackets such as
     [filename] are optional. Numeric inputs are shown as nn for decimal, and xx
     for hex. In either case, prefixing the number with "#" selects  the  alter-
     nate number system.

     Multiple commands on a line are allowed, separated by semicolons.

     +[x]   Increase  the  current  sector  number by [x] and read the resulting
	    sector, incrementing the track if necessary.

     -[x]   Decrease the current sector number by [x]  and  read  the  resulting
	    sector, decrementing the track if necessary.

     #	    Display the disc geometry for the current drive/disc image.

     $[variable[=value]]
	    View  and amend the geometry. "$" by itself shows all possible vari-
	    ables with their current values; "$variable" shows the value of  one
	    variable; and "$variable=value" sets a new value. Note that changing
	    the  size  of  the	sector with "$secsize=nn" will cause the current
	    sector buffer and clip buffer to be cleared.

     =ascii Search for an ASCII string, starting  at  the  current  sector.  Hex
	    codes  can	be  included in the ASCII by surrounding them with angle
	    brackets - for example, to search for the word "Hello" at the  start
	    of	a  line,  you could use "=<0A>Hello". The search string is case-
	    sensitive.

     <	    Save the currently-loaded sector to a clip buffer.

     >	    Restore the contents of  the  clip	buffer	to  the  current  sector
	    buffer.

     ?	    Display a command summary.

     A[from,to]
	    Dump  the contents of the sector buffer as ASCII. If from and to are
	    included, then only values between those offsets will be shown.

     CHoffset,value,value,value...
	    Change bytes in the current sector buffer. The offset and values are
	    in hex.

     CAoffset,ascii
	    Replace bytes in the current sector buffer with an ASCII string.  As
	    with  the  "="  command, the ASCII can contain embedded hex bytes in
	    angle brackets.

     CHfrom-to,value,value,value...
	    The same as CH above, but fills the range from from to to  with  the
	    byte sequence, repeating or truncating it as necessary.

     CAfrom-to,ascii
	    The same as CHfrom-to, except that the byte sequence is specified as
	    ASCII.

     D[from,to]
	    Dump the contents of the sector buffer as ASCII and hex.

     Gxx    Go to logical sector number xx

     H[from,to]
	    Dump the contents of the sector buffer as hex.

     Kfilename
	    Save  all "yanked" sectors (see Y below) to the specified file. This
	    also clears them from memory.

     Lfilename[,type[,compression]]
	    Open a new drive or disc image. If this has a different sector  size
	    from the current sector size, the sector buffer and clip buffer will
	    be cleared.

     N[geometry]
	    Change geometry. N by itself re-runs the automatic probe; N with the
	    name of a geometry selects one of the formats known to LibDsk.

     R	    (Re)read the current sector.

     Snn    Set the current sector number, and read.

     Tnn    Set the current track number. Does not read.

     V	    Compare the contents of the sector buffer with the current sector on
	    disc.

     W	    Write the sector buffer to disc.

     X	    Leave dskutil.

     Y	    Append  the  current sector to a "yank" buffer. It can then be saved
	    with the K command.

     Z[nn]  Sleep for nn seconds; if nn is not present, sleeps for one second.

     /nn    This must be the last command on a line. It  repeats  the  preceding
	    line nn times.

BUGS
     On  platforms  with no sleep(3) function, the Z command works by busy-wait-
     ing.

     Commands are always input using fgets(3), even when the  host  system  pro-
     vides a more sophisticated input method such as readline(3).

     While  the  current  feature  set is a fairly good match for DU90 (less the
     features specific to the CP/M filesystem) it doesn't cover all the features
     of LibDsk.

AUTHOR
     John Elliott <seasip.webmaster@gmail.com>.

Version 1.2.1			 23 January 2008		      dskutil(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=dskutil&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

home | help