Posted On 2007-04-27 by FortyPoundHead
Keywords: Command Reference
Tags: Linux Commandline Linux
Views: 1580

Dump Data - convert and copy a file (use for RAW storage), create a boot floppy.

dd [OPTION]...

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::).

input file : Read from FILE instead of standard input.

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='').

Read BYTES bytes at a time.

Write BYTES bytes at a time.

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

Convert BYTES bytes at a time.

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

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

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

Convert the file as specified by the CONVERSION argument(s).
(No spaces around any comma)


Convert EBCDIC to ASCII.

Convert ASCII to EBCDIC.

Convert ASCII to alternate EBCDIC.

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

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

Change uppercase letters to lowercase.

Change lowercase letters to uppercase.

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).

Continue after read errors.

Do not truncate the output file.

Pad every input block to size of `ibs'' with trailing zero
dd can be used to create a boot floppy:

dd if=boot.img of=/dev/fd0 bs=1440


if = the input file or device
of = the output file or device
bs = the block size for both input and output files

About the Author

FortyPoundHead has posted a total of 1974 articles.


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