Difference between revisions of "cmd/dd"

Latest revision as of 22:37, 13 November 2022

Documentation

NAME

dd - convert and copy a file

SYNOPSIS

dd [OPTION]...

DESCRIPTION

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

BLOCKS and BYTES may be followed by the following multiplicative suffixes: xM M, c 1, w 2, b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, 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; when used with block or unblock, pad with spaces rather than NULs

Note that sending a SIGUSR1 signal to a running `dd' process makes it print to standard error the number of records read and written so far, then to resume copying.

$ dd if=/dev/zero of=/dev/null& pid=$! 
$ kill -USR1 $pid; sleep 1; kill $pid 
10899206+0 records in 10899206+0 records out

AUTHOR

Written by Paul Rubin, David MacKenzie, and Stuart Kemp.

REPORTING BUGS

Report bugs to <bug-coreutils@gnu.org>.

COPYRIGHT

Edit Log

2005-06-25 Created from Linux manpage (Ubuntu hoary)

@@ Line 1: / Line 1: @@
-[[Category:Linux
-Shell Commands]]
-[[Techniques]]: [[Linux]]: [[dd]]
 ==Documentation==
 ===NAME===
-[[dd]] - convert and copy a file ===SYNOPSIS===
+{{l/cmd|dd}} - convert and copy a file
-[[dd]] [''OPTION'']... ===DESCRIPTION===
+===SYNOPSIS===
-Copy a file, converting and formatting according to the options.
+{{l/cmd|dd}} [''OPTION'']...
+===DESCRIPTION===
+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 ''BYTES'' bytes at a time
-:convert the file as per the comma separated keyword list
+*'''conv='''''KEYWORDS''
+:convert the file as per the comma separated keyword list
 *'''count='''''BLOCKS''
-:copy only ''BLOCKS'' input blocks *'''ibs='''''BYTES''
+:copy only ''BLOCKS'' input blocks
-:read ''BYTES'' bytes at a time *'''if='''''FILE''
+*'''ibs='''''BYTES''
-:read from ''FILE'' instead of stdin *'''obs='''''BYTES''
+:read ''BYTES'' bytes at a time
-:write ''BYTES'' bytes at a time *'''of='''''FILE''
+*'''if='''''FILE''
-:write to ''FILE'' instead of stdout *'''seek='''''BLOCKS''
+:read from ''FILE'' instead of stdin
-:skip ''BLOCKS'' ''obs''-sized blocks at start of output
+*'''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'''
+:skip ''BLOCKS'' ''ibs''-sized blocks at start of input
-:display this help and exit *'''--version'''
+*'''--help'''
-:output version information and exit ''BLOCKS'' and ''BYTES'' may be
+:display this help and exit
-followed by the following multiplicative suffixes: xM M, c 1, w 2, b
+*'''--version'''
-, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G
+:output version information and exit
-*1024*1024, and so on for T, P, E, Z, Y.
+''BLOCKS'' and ''BYTES'' may be followed by the following multiplicative suffixes: xM M, c 1, w 2, b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, 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
+Each ''KEYWORD'' may be:
-alternated EBCDIC *'''block''' - pad newline-terminated records with
+*'''ascii''' - from EBCDIC to ASCII
-spaces to cbs-size *'''unblock''' - replace trailing spaces in cbs-size
+*'''ebcdic''' - from ASCII to EBCDIC
-records with newline *'''lcase''' - change upper case to lower case
+*'''ibm''' - from ASCII to alternated EBCDIC
-*'''notrunc''' - do not truncate the output file *'''ucase''' - change
+*'''block''' - pad newline-terminated records with spaces to cbs-size
-lower case to upper case *'''swab''' - swap every pair of input bytes
+*'''unblock''' - replace trailing spaces in cbs-size records with newline
-*'''noerror''' - continue after read errors *'''sync''' - pad every
+*'''lcase''' - change upper case to lower case
-input block with NULs to ibs-size; when used with block or unblock, pad
+*'''notrunc''' - do not truncate the output file
-with spaces rather than NULs Note that sending a SIGUSR1 signal to a
+*'''ucase''' - change lower case to upper case
-running `dd' process makes it print to standard error the number of
+*'''swab''' - swap every pair of input bytes
-records read and written so far, then to resume copying. $ dd
+*'''noerror''' - continue after read errors
-if=/dev/zero of=/dev/null& pid=$! $ kill -USR1 $pid; sleep 1; kill
+*'''sync''' - pad every input block with NULs to ibs-size; when used with block or unblock, pad with spaces rather than NULs
-$pid 10899206+0 records in 10899206+0 records out ===AUTHOR===
-Written by Paul Rubin, David MacKenzie, and Stuart Kemp. ===REPORTING
+Note that sending a SIGUSR1 signal to a running `dd' process makes it print to standard error the number of records read and written so far, then to resume copying.
-BUGS===
+ $ dd if=/dev/zero of=/dev/null& pid=$!
-Report bugs to <bug-coreutils@gnu.org>. ===COPYRIGHT===
+ $ kill -USR1 $pid; sleep 1; kill $pid
-Copyright &copy; 2004 Free Software Foundation, Inc. This is free
+ 10899206+0 records in 10899206+0 records out
-software; see the source for copying conditions. There is NO warranty;
+===AUTHOR===
-not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+Written by Paul Rubin, David MacKenzie, and Stuart Kemp.
+===REPORTING BUGS===
+Report bugs to <bug-coreutils@gnu.org>.
+===COPYRIGHT===
+Copyright &copy; 2004 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 ===SEE ALSO===
-The full documentation for dd is maintained as a Texinfo manual. If the
+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 and dd programs are properly installed at your site, the command
+ info coreutils dd
-info coreutils dd should give you access to the complete manual.
+should give you access to the complete manual.
 ==Edit Log==
 *'''2005-06-25''' Created from Linux manpage (Ubuntu hoary)