dd(1)

NAME
dd - Copy, and optionally convert, a file system resource

SYNOPSIS
dd [-h|--help] [-V|--version] [operands]

DESCRIPTION
Copy, and optionally convert, a file system resource

OPTIONS

-h, --help
    Print help

-V, --version
    Print version

[operands]

EXTRA
### Operands

- bs=BYTES : read and write up to BYTES bytes at a time (default: 512);
   overwrites ibs and obs. - cbs=BYTES : the 'conversion block size' in bytes. Applies to the
   conv=block, and conv=unblock operations. - conv=CONVS : a comma-separated list of conversion options or (for legacy
   reasons) file flags. - count=N : stop reading input after N ibs-sized read operations rather
   than proceeding until EOF. See iflag=count_bytes if stopping after N bytes
   is preferred - ibs=N : the size of buffer used for reads (default: 512) - if=FILE : the file used for input. When not specified, stdin is used instead - iflag=FLAGS : a comma-separated list of input flags which specify how the
   input source is treated. FLAGS may be any of the input-flags or general-flags
   specified below. - skip=N (or iseek=N) : skip N ibs-sized records into input before beginning
   copy/convert operations. See iflag=seek_bytes if seeking N bytes is preferred. - obs=N : the size of buffer used for writes (default: 512) - of=FILE : the file used for output. When not specified, stdout is used
   instead - oflag=FLAGS : comma separated list of output flags which specify how the
   output source is treated. FLAGS may be any of the output flags or general
   flags specified below - seek=N (or oseek=N) : seeks N obs-sized records into output before
   beginning copy/convert operations. See oflag=seek_bytes if seeking N bytes is
   preferred - status=LEVEL : controls whether volume and performance stats are written to
   stderr.

  When unspecified, dd will print stats upon completion. An example is below.

  plain
    6+0 records in
    16+0 records out
    8192 bytes (8.2 kB, 8.0 KiB) copied, 0.00057009 s,
    14.4 MB/s

  The first two lines are the 'volume' stats and the final line is the
  'performance' stats.
  The volume stats indicate the number of complete and partial ibs-sized reads,
  or obs-sized writes that took place during the copy. The format of the volume
  stats is <complete>+<partial>. If records have been truncated (see
  conv=block), the volume stats will contain the number of truncated records.

  Possible LEVEL values are:
  - progress : Print periodic performance stats as the copy proceeds.
  - noxfer : Print final volume stats, but not performance stats.
  - none : Do not print any stats.

  Printing performance stats is also triggered by the INFO signal (where supported),
  or the USR1 signal. Setting the POSIXLY_CORRECT environment variable to any value
  (including an empty value) will cause the USR1 signal to be ignored.

### Conversion Options

- ascii : convert from EBCDIC to ASCII. This is the inverse of the ebcdic
  option. Implies conv=unblock. - ebcdic : convert from ASCII to EBCDIC. This is the inverse of the ascii
  option. Implies conv=block. - ibm : convert from ASCII to EBCDIC, applying the conventions for [, ]
  and ~ specified in POSIX. Implies conv=block.

- ucase : convert from lower-case to upper-case. - lcase : converts from upper-case to lower-case.

- block : for each newline less than the size indicated by cbs=BYTES, remove
  the newline and pad with spaces up to cbs. Lines longer than cbs are truncated. - unblock : for each block of input of the size indicated by cbs=BYTES, remove
  right-trailing spaces and replace with a newline character.

- sparse : attempts to seek the output when an obs-sized block consists of
  only zeros. - swab : swaps each adjacent pair of bytes. If an odd number of bytes is
  present, the final byte is omitted. - sync : pad each ibs-sided block with zeros. If block or unblock is
  specified, pad with spaces instead. - excl : the output file must be created. Fail if the output file is already
  present. - nocreat : the output file will not be created. Fail if the output file in
  not already present. - notrunc : the output file will not be truncated. If this option is not
  present, output will be truncated when opened. - noerror : all read errors will be ignored. If this option is not present,
  dd will only ignore Error::Interrupted. - fdatasync : data will be written before finishing. - fsync : data and metadata will be written before finishing.

### Input flags

- count_bytes : a value to count=N will be interpreted as bytes. - skip_bytes : a value to skip=N will be interpreted as bytes. - fullblock : wait for ibs bytes from each read. zero-length reads are still
  considered EOF.

### Output flags

- append : open file in append mode. Consider setting conv=notrunc as well. - seek_bytes : a value to seek=N will be interpreted as bytes.

### General Flags

- direct : use direct I/O for data. - directory : fail unless the given input (if used as an iflag) or
  output (if used as an oflag) is a directory. - dsync : use synchronized I/O for data. - sync : use synchronized I/O for data and metadata. - nonblock : use non-blocking I/O. - noatime : do not update access time. - nocache : request that OS drop cache. - noctty : do not assign a controlling tty. - nofollow : do not follow system links.

VERSION
v0.0.30