dd

Dump Data - convert and copy a file (use for RAW storage)

SYNTAX
     dd [OPTION]...

DESCRIPTION
     The numeric-valued options below (BYTES and BLOCKS) can be followed
     by a multiplier: `b'=512, `c'=1, `w'=2, `xM'=M, or any of the standard
     block size suffixes like `k'=1024 (*note Block size::).

`if=FILE'
     input file : Read from FILE instead of standard input.

`of=FILE'
     output file : Write to FILE instead of standard output.  Unless `conv=notrunc'
     is given, `dd' truncates FILE to zero bytes (or the size specified
     with `seek=').

`ibs=BYTES'
     Read BYTES bytes at a time.

`obs=BYTES'
     Write BYTES bytes at a time.

`bs=BYTES'
     Both read and write BYTES bytes at a time.  This overrides `ibs'
     and `obs'.

`cbs=BYTES'
     Convert BYTES bytes at a time.

`skip=BLOCKS'
     Skip BLOCKS `ibs'-byte blocks in the input file before copying.

`seek=BLOCKS'
     Skip BLOCKS `obs'-byte blocks in the output file before copying.

`count=BLOCKS'
     Copy BLOCKS `ibs'-byte blocks from the input file, instead of
     everything until the end of the file.

`conv=CONVERSION[,CONVERSION]...'
     Convert the file as specified by the CONVERSION argument(s).  (No
     spaces around any comma(s).)

     Conversions:

    `ascii'
          Convert EBCDIC to ASCII.

    `ebcdic'
          Convert ASCII to EBCDIC.

    `ibm'
          Convert ASCII to alternate EBCDIC.

    `block'
          For each line in the input, output `cbs' bytes, replacing the
          input newline with a space and padding with spaces as
          necessary.

    `unblock'
          Replace trailing spaces in each `cbs'-sized input block with a
          newline.

    `lcase'
          Change uppercase letters to lowercase.

    `ucase'
          Change lowercase letters to uppercase.

    `swab'
          Swap every pair of input bytes.  GNU `dd', unlike others,
          works when an odd number of bytes are read--the last byte is
          simply copied (since there is nothing to swap it with).

    `noerror'
          Continue after read errors.

    `notrunc'
          Do not truncate the output file.

    `sync'
          Pad every input block to size of `ibs' with trailing zero
          bytes.


"Dying is the most embarrassing thing that can happen to you, because someones got to take care of all your details". - Andy Warhol

Related commands:

cp - Copy one or more files to another location
install - Copy files and set attributes
mtools - Manipulate MS-DOS files
mv - Move or rename files or directories
nl - Number lines and write files
sum - Print a checksum for a file

Equivalent Windows NT commands:

NTBACKUP - Backup folders to tape
ROBOCOPY
- Robust File and Folder Copy



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Simon Sheppard
SS64.com