Name
dd
Synopsis
dd [option
=value
]
Makes a copy of an input file (if=) or standard input if there’s no named input file, using the specified conditions, and sends the results to the output file (or standard output if of isn’t specified). Any number of options can be supplied, although if and of are the most common and are usually specified first. Because dd can handle arbitrary block sizes, it is useful when converting between raw physical devices.
dd doesn’t preserve resource forks or HFS metadata when copying files that contain them.
Options
-
bs=
n
Set input and output block size to
n
bytes; this option supersedes ibs and obs.-
cbs=
n
Set the size of the conversion buffer (logical record length) to
n
bytes. Use only if the conversionflag
is ascii, asciib, ebcdic, ebcdicb, ibm, ibmb, block, or unblock.-
conv=
flags
Convert the input according to one or more (comma-separated)
flags
listed next. The first sixflags
are mutually exclusive. The next two are mutually exclusive with each other, as are the following two.- ascii
EBCDIC to ASCII.
- asciib
EBCDIC to ASCII, using BSD-compatible conversions.
- ebcdic
ASCII to EBCDIC.
- ebcdicb
ASCII to EBCDIC, using BSD-compatible conversions.
- ibm
ASCII to EBCDIC with IBM conventions.
- ibmb
ASCII to EBCDIC with IBM conventions, using BSD-compatible conversions.
- block
Variable-length records (i.e., those terminated by a newline) to fixed-length records.
- unblock
Fixed-length records to variable length.
- lcase
Uppercase to lowercase.
- ucase
Lowercase to uppercase. ...
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