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DC3DD(1)			  User Commands 			DC3DD(1)

NAME
     dc3dd - convert and copy a file

DESCRIPTION
     ------ usage: ------

	    dc3dd [OPTION 1] [OPTION 2] ... [OPTION N]

	    *or*

	    dc3dd [HELP OPTION]

	    where  each  OPTION  is  selected from the basic or advanced options
	    listed below, or HELP OPTION  is  selected	from  the  help  options
	    listed below.

     -------------- basic options: --------------

     if=DEVICE or FILE
	    Read  input  from  a  device or a file (see note #1 below for how to
	    read from standard input). This option can only  be  used  once  and
	    cannot be combined with ifs=, pat=, or tpat=.

     ifs=BASE.FMT
	    Read  input  from  a set of files with base name BASE and sequential
	    file name extensions conforming to the  format  specifier  FMT  (see
	    note  #4 below for how to specify FMT). This option can only be used
	    once and cannot be combined with if=, pat=, or tpat=.

     of=FILE or DEVICE
	    Write output to a file or device (see note #2 below for how to write
	    to standard output). This option can be used  more	than  once  (see
	    note #3 below for how to generate multiple outputs).

     hof=FILE or DEVICE
	    Write  output to a file or device, hash the output bytes, and verify
	    by comparing the output hash(es) to the input hash(es). This  option
	    can  be  used  more than once (see note #3 below for how to generate
	    multiple outputs).

     ofs=BASE.FMT
	    Write output to a set of files with base name  BASE  and  sequential
	    file  name	extensions  generated from the format specifier FMT (see
	    note #4 below for how to specify FMT). This option can be used  more
	    than  once (see note #3 below for how to generate multiple outputs).
	    Specify the maximum size of each file in the set using ofsz=.

     hofs=BASE.FMT
	    Write output to a set of files with base name  BASE  and  sequential
	    file  name	extensions  generated from the format specifier FMT (see
	    note #4 below for how to specify FMT). Hash  the  output  files  and
	    verify  by comparing the output hash(es) to the input hash(es). This
	    option can be used more than once (see note #3 below for how to gen-
	    erate multiple outputs). Specify the maximum size of  each	file  in
	    the set using ofsz=.

     ofsz=BYTES
	    Set the maximum size of each file in the sets of files specified us-
	    ing  ofs= or hofs= to BYTES (see note #5 below). A default value for
	    this  option  may  be  set	at  compile  time  using  -DDEFAULT_OUT-
	    PUT_FILE_SIZE followed by the desired value in BYTES.

     hash=ALGORITHM
	    Compute an ALGORITHM hash of the input and also of any outputs spec-
	    ified  using  hof=,  hofs=, or fhod=, where ALGORITHM is one of md5,
	    sha1, sha256, or sha512. This option may be used once for each  sup-
	    ported ALGORITHM. Alternatively, hashing can be activated at compile
	    time  using  one  or more of -DDEFAULT_HASH_MD5,-DDEFAULT_HASH_SHA1,
	    -DDEFAULT_HASH_SHA256, and -DDEFAULT_HASH_SHA512.

     log=FILE
	    Log I/O statistcs, diagnostics, and total hashes of input and output
	    to FILE. If hlog= is not specified,  piecewise  hashes  of	multiple
	    file  input  and  output are also logged to FILE. This option can be
	    used more than once to generate multiple logs.

     hlog=FILE
	    Log total hashes and piecewise hashes to FILE.  This option  can  be
	    used more than once to generate multiple logs.

     mlog=FILE
	    Create hash log that is easier for machine to read

     ----------------- advanced options: -----------------

     fhod=DEVICE
	    The same as hof=DEVICE, with additional hashing of the entire output
	    DEVICE.  This  option  can be used more than once (see note #3 below
	    for how to generate multiple outputs).

     rec=off
	    By default, zeros are written to the output(s) in place of bad  sec-
	    tors  when the input is a device.  Use this option to cause the pro-
	    gram to instead exit when a bad sector is encountered.

     wipe=DEVICE
	    Wipe DEVICE by writing zeros (default) or  a  pattern  specified  by
	    pat= or tpat=.

     hwipe=DEVICE
	    Wipe  DEVICE  by  writing  zeros (default) or a pattern specified by
	    pat= or tpat=. Verify DEVICE after writing it by hashing it and com-
	    paring the hash(es) to the input hash(es).

     pat=HEX
	    Use pattern as input, writing HEX to every byte of the output.  This
	    option  can only be used once and cannot be combined with if=, ifs=,
	    or tpat=.

     tpat=TEXT
	    Use text pattern as input, writing the string TEXT repeatedly to the
	    output. This option can only be used once  and  cannot  be	combined
	    with if=, ifs=, or pat=.

     cnt=SECTORS
	    Read  only SECTORS input sectors. Must be used with pat= or tpat= if
	    not using the pattern with wipe= or hwipe= to wipe a device.

     iskip=SECTORS
	    Skip SECTORS sectors at start of the input device or file.

     oskip=SECTORS
	    Skip SECTORS sectors at start of the output file. Specifying  oskip=
	    automatically sets app=on.

     app=on
	    Do not overwrite an output file specified with of= if it already ex-
	    ists, appending output instead.

     ssz=BYTES
	    Unconditionally use BYTES (see note #5 below) bytes for sector size.
	    If	ssz=  is not specified, sector size is determined by probing the
	    device; if the probe fails or the target is not a device,  a  sector
	    size of 512 bytes is assumed.

     bufsz=BYTES
	    Set  the size of the internal byte buffers to BYTES (see note #5 be-
	    low). This effectively sets the maximum number of bytes that may  be
	    read  at  a  time from the input. BYTES must be a multiple of sector
	    size. Use this option to fine-tune performance.

     verb=on
	    Activate verbose reporting, where sectors in/out  are  reported  for
	    each  file	in  sets  of files specified using ifs=, ofs=, or hofs=.
	    Alternatively, verbose reporting may be activated  at  compile  time
	    using -DDEFAULT_VERBOSE_REPORTING.

     nwspc=on
	    Activate  compact  reporting, where the use of white space to divide
	    log output into logical sections is suppressed. Alternatively,  com-
	    pact reporting may be activated at compile time using -DDEFAULT_COM-
	    PACT_REPORTING.

     b10=on
	    Activate base 10 bytes reporting, where the progress display reports
	    1000  bytes  instead  of  1024 bytes as 1 KB. Alternatively, base 10
	    bytes reporting  may  be  activated  at  compile  time  using  -DDE-
	    FAULT_BASE_TEN_BYTES_REPORTING.

     corruptoutput=on
	    For  verification  testing	and  demonstration purposes, corrupt the
	    output file(s) with extra bytes so a hash mismatch is guaranteed.

     ------------- help options: -------------

     --help
	    display this help and exit

     --version
	    output version information and exit

     --flags
	    display compile-time flags and exit

     ------ notes: ------

     1. To read from stdin, do not specify if=, ifs=, pat=,  or  tpat=.   2.  To
     write to stdout, do not specify of=, hof=, ofs=, hofs=, fhod=,

	    wipe=, or hwipe=.

     3. To write to multiple outputs specify more than one of of=, hof=, ofs=,

	    hofs=, or fhod=, in any combination.

     4. FMT is a pattern for a sequence of file extensions that can be numerical

	    starting  at zero, numerical starting at one, or alphabetical. Spec-
	    ify FMT by using a series of zeros, ones, or a's, respectively.  The
	    number of characters used indicates the desired length of the exten-
	    sions.   For example, a FMT specifier of 0000 indicates four charac-
	    ter numerical extensions starting with 0000.

   5. BYTES may be followed by the following multiplicative suffixes:
	    c (1), w (2), b (512),  kB	(1000),  K  (1024),  MB  (1000*1000),  M
	    (1024*1024),  GB (1000*1000*1000), G (1024*1024*1024), and so on for
	    T, P, E, Z, and Y.

     6. Consider using cnt=, iskip= and oskip= to work around

	    unreadable sectors if error recovery fails.

     7. Sending an interrupt (e.g., CTRL+C) to dc3dd will cause

	    the program to report the work completed at the time  the  interrupt
	    is received and then exit.

     dc3dd completed at 2023-04-04 18:08:06 -0400

AUTHOR
     Written by Paul Rubin, David MacKenzie, Stuart Kemp, Jesse Kornblum, Andrew
     Medico,  Richard  Cordovano,  Justin  Lowe,  Frank  Westerman,  and  Joseph
     Lininger.

REPORTING BUGS
     Report bugs to <dc3dd@dc3.mil>.

COPYRIGHT
     Copyright (C) 2008 Free Software Foundation, Inc.	License GPLv3+: GNU  GPL
     version 3 or later <http://gnu.org/licenses/gpl.html>
     This  is  free software: you are free to change and redistribute it.  There
     is NO WARRANTY, to the extent permitted by law.

SEE ALSO
     The full documentation for dc3dd is maintained as a Texinfo manual.  If the
     info and dc3dd programs are properly installed at your site, the command

	    info dc3dd

     should give you access to the complete manual.

dc3dd 7.3.1			   April 2023				DC3DD(1)

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