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DD(1)				 User Commands				 DD(1)

NAME
       dd - convert and	copy a file

SYNOPSIS
       dd [OPERAND]...
       dd OPTION

DESCRIPTION
       Copy a file, converting and formatting according	to the operands.

       bs=BYTES
	      read and write up	to BYTES bytes at a time (default: 512); over-
	      rides ibs	and obs

       cbs=BYTES
	      convert BYTES bytes at a time

       conv=CONVS
	      convert the file as per the comma	separated symbol list

       count=N
	      copy only	N input	blocks

       ibs=BYTES
	      read up to BYTES bytes at	a time (default: 512)

       if=FILE
	      read from	FILE instead of	stdin

       iflag=FLAGS
	      read as per the comma separated symbol list

       obs=BYTES
	      write BYTES bytes	at a time (default: 512)

       of=FILE
	      write to FILE instead of stdout

       oflag=FLAGS
	      write as per the comma separated symbol list

       seek=N skip N obs-sized blocks at start of output

       skip=N skip N ibs-sized blocks at start of input

       status=LEVEL
	      The LEVEL	of information to print	to stderr;  'none'  suppresses
	      everything  but  error  messages,	 'noxfer' suppresses the final
	      transfer statistics, 'progress' shows periodic transfer  statis-
	      tics

       N  and  BYTES may be followed by	the following multiplicative suffixes:
       c=1, w=2, b=512,	 kB=1000,  K=1024,  MB=1000*1000,  M=1024*1024,	 xM=M,
       GB=1000*1000*1000,  G=1024*1024*1024, and so on for T, P, E, Z, Y.  Bi-
       nary prefixes can be used, too: KiB=K, MiB=M, and so on.

       Each CONV symbol	may be:

       ascii  from EBCDIC to ASCII

       ebcdic from ASCII to EBCDIC

       ibm    from ASCII to alternate 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

       ucase  change lower case	to upper case

       sparse try to seek rather than write all-NUL output blocks

       swab   swap every pair of input bytes

       sync   pad every	input block with NULs  to  ibs-size;  when  used  with
	      block or unblock,	pad with spaces	rather than NULs

       excl   fail if the output file already exists

       nocreat
	      do not create the	output file

       notrunc
	      do not truncate the output file

       noerror
	      continue after read errors

       fdatasync
	      physically write output file data	before finishing

       fsync  likewise,	but also write metadata

       Each FLAG symbol	may be:

       append append  mode  (makes  sense  only	 for output; conv=notrunc sug-
	      gested)

       direct use direct I/O for data

       directory
	      fail unless a directory

       dsync  use synchronized I/O for data

       sync   likewise,	but also for metadata

       fullblock
	      accumulate full blocks of	input (iflag only)

       nonblock
	      use non-blocking I/O

       nocache
	      Request to drop cache.  See also oflag=sync

       noctty do not assign controlling	terminal from file

       nofollow
	      do not follow symlinks

       count_bytes
	      treat 'count=N' as a byte	count (iflag only)

       skip_bytes
	      treat 'skip=N' as	a byte count (iflag only)

       seek_bytes
	      treat 'seek=N' as	a byte count (oflag only)

       Sending a INFO signal to	a running 'dd' process makes it	print I/O sta-
       tistics to standard error and then resume copying.

       Options are:

       --help display this help	and exit

       --version
	      output version information and exit

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

REPORTING BUGS
       GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
       Report any translation bugs to <https://translationproject.org/team/>

COPYRIGHT
       Copyright  (C) 2020 Free	Software Foundation, Inc.  License GPLv3+: GNU
       GPL version 3 or	later <https://gnu.org/licenses/gpl.html>.
       This is free software: you are free  to	change	and  redistribute  it.
       There is	NO WARRANTY, to	the extent permitted by	law.

SEE ALSO
       Full documentation <https://www.gnu.org/software/coreutils/dd>
       or available locally via: info '(coreutils) dd invocation'

GNU coreutils 8.32		  March	2020				 DD(1)

NAME | SYNOPSIS | DESCRIPTION | AUTHOR | REPORTING BUGS | COPYRIGHT | SEE ALSO

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