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dd - convert and copy a file
dd [OPTION]...
Copy a
file, converting and formatting according to the options.
- bs=BYTES
- force
ibs=BYTES and obs=BYTES
- cbs=BYTES
- convert BYTES bytes at a time
- conv=KEYWORDS
- convert the file as per the comma separated keyword list
- count=BLOCKS
- copy
only BLOCKS input blocks
- ibs=BYTES
- read BYTES bytes at a time
- if=FILE
- read
from FILE instead of stdin
- obs=BYTES
- write BYTES bytes at a time
- of=FILE
- write to FILE instead of stdout
- seek=BLOCKS
- skip BLOCKS obs-sized blocks
at start of output
- skip=BLOCKS
- skip BLOCKS ibs-sized blocks at start of
input
- --help
- display this help and exit
- --version
- output version information
and exit
BYTES may be followed by the following multiplicative suffixes:
xM M, c 1, w 2, b 512, kD 1000, k 1024, MD 1,000,000, M 1,048,576, GD 1,000,000,000,
G 1,073,741,824, and so on for T, P, E, Z, Y. Each KEYWORD may be:
- ascii
- from EBCDIC to ASCII
- ebcdic
- from ASCII to EBCDIC
- ibm
- from ASCII to alternated
EBCDIC
- block
- pad newline-terminated records with spaces to cbs-size
- unblock
- replace trailing spaces in cbs-size records with newline
- lcase
- change upper
case to lower case
- notrunc
- do not truncate the output file
- ucase
- change
lower case to upper case
- swab
- swap every pair of input bytes
- noerror
- continue
after read errors
- sync
- pad every input block with NULs to ibs-size
Report bugs to <bug-fileutils@gnu.org>.
The full documentation for
dd is maintained as a Texinfo manual. If the info and dd programs are properly
installed at your site, the command
- info dd
should give you access to the
complete manual.
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