-
- dd - convert and copy a file
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- dd [ options ]
-
- dd copies an input file to an output file with optional conversions. The standard input and output are used by default. Input and output block sizes can
be specified to take advantage of physical io limitations. Options are of the form name=value and may be specified with 0, 1, or 2 leading `-' characters.
- A number argument may be a scaled number with optional trailing multipliers of the form `* number', `x number' or `X number'. Scale
suffixes may be one of:
- b|B
- 512
- c|C
- 1
- g|G
- 1073741824
- k|K
- 1024
- l|L
- 4
- m|M
- 1048576
- q|Q
- 8
- w|W
- 2
-
- bs=number
- Input and output block size.
- cbs=number
- Conversion buffer size (logical record length).
- conv=conversion
- Convert input. conversion may be one of:
- a2e
- ascii to ebcdic
- a2i
- ascii to ibm
- a2n
- ascii to native
- a2o
- ascii to open edition ebcdic
- ascii
- ebcdic to ascii
- block
- newline-terminated ascii to fixed record length
- e2a
- ebcdic to ascii
- ebcdic
- equivalent to a2e
- i2a
- ibm to ascii
- ibm
- ascii to ibm ebcdic
- ignerror
- continue processing after errors
- ispecial
- currently ignored
- lcase
- to lower case
- n2a
- native to ascii
- noerror
- stop processing only after 5 consecutive errors
- notrunc
- do not truncate pre-existing output files
- o2a
- open edition ibm to ascii
- ospecial
- currently ignored
- swab
- swap byte pairs
- sync
- Pad each input block to ibs. Pad with spaces if conv=block or conv=unblock, otherwise pad with nulls.
- ucase
- to upper case
- unblock
- fixed-length records to newline-terminated records
- count=number
- Copy only number input blocks.
- from=codeset
- Convert from codeset to the to=codeset or the local default. codeset names are matched by
left-anchored case-insensitive ksh(1) patterns. codeset may be one of:
- a|ascii|?(iso)?(-)646|?(iso)?(-)8859|latin
- 8 bit ascii
- e|ebcdic?(-)?([1e])
- X/Open ebcdic
- o|ebcdic?(-)[3o]|?(cp|ibm)1047|open?(-)edition
- mvs OpenEdition ebcdic
- h|ebcdic?(-)h|?(cp|ibm)?(00)37|[oa]s?(/-)400
- ibm OS/400 AS/400 ebcdic
- s|ebcdic?(-)s|siemens|posix-bc
- siemens posix-bc ebcdic
- i|ebcdic?(-)[2i]|ibm
- X/Open ibm ebcdic (not idempotent)
- m|ebcdic?(-)m|mvs
- mvs ebcdic
- u|ebcdic?(-)(u|mf)|microfocus
- microfocus cobol ebcdic
- n|native|local
- native code set
- un|unicode|utf
- multibyte 8-bit unicode
- um|ume|utf?(-)7
- multibyte 7-bit unicode
- (big|euc)*
- euc family
- dos?(-)?(855)
- dos code page
- ucs?(-)?(2)?(be)|utf-16?(be)
- unicode runes
- ucs?(-)?(2)le|utf-16le
- little endian unicode runes
- ibs=number
- Input block size.
- if=file
- The input file name; standard input is the default.
- iseek=number
- Seek number blocks from the beginning of the input file before copying.
- obs=number
- Output block size.
- of=file
- The output file name; standard output is the default.
- oseek|seek=number
- Seek number blocks from the beginning of the output file before copying.
- silent
- silent does not print the total number of io blocks on exit.
- skip=number
- Skip number blocks before reading. Seek is used if possible, otherwise the blocks are read and discarded.
- swap=number
- Swap bytes acording to the inclusive or of: 1-byte, 2-short, 4-long, 8-quad, etc.
- to=codeset
- Convert to codeset from the from=codeset or the local default. See from for codeset names.
-
- cp(1), iconv(1), pax(1),
tr(1), seek(2)
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- version
- dd (AT&T Research) 2005-07-17
- author
- Glenn Fowler <gsf@research.att.com>
- copyright
- Copyright © 1989-2008 AT&T Intellectual Property
- license
- http://www.opensource.org/licenses/cpl1.0.txt