ddrescue(1)

NAME

   ddrescue - data recovery tool

SYNOPSIS

   ddrescue [options] infile outfile [mapfile]

DESCRIPTION

   GNU  ddrescue - Data recovery tool.  Copies data from one file or block
   device to another, trying to rescue the good parts  first  in  case  of
   read errors.

   Always  use  a  mapfile  unless  you  know you won't need it. Without a
   mapfile, ddrescue can't resume a rescue, only reinitiate it.  NOTE:  In
   versions  of  ddrescue  prior to 1.20 the mapfile was called 'logfile'.
   The format is the same; only the name has changed.

   If you reboot, check  the  device  names  before  restarting  ddrescue.
   Don't use options '-F' or '-G' without reading the manual first.

OPTIONS

   -h, --help
          display this help and exit

   -V, --version
          output version information and exit

   -a, --min-read-rate=<bytes>
          minimum read rate of good areas in bytes/s

   -A, --try-again
          mark non-trimmed, non-scraped as non-tried

   -b, --sector-size=<bytes>
          sector size of input device [default 512]

   -B, --binary-prefixes
          show binary multipliers in numbers [SI]

   -c, --cluster-size=<sectors>
          sectors to copy at a time [128]

   -C, --complete-only
          don't read new data beyond mapfile limits

   -d, --idirect
          use direct disc access for input file

   -D, --odirect
          use direct disc access for output file

   -e, --max-errors=[+]<n>
          maximum number of [new] error areas allowed

   -E, --max-error-rate=<bytes>
          maximum allowed rate of read errors per second

   -f, --force
          overwrite output device or partition

   -F, --fill-mode=<types>
          fill blocks of given types with data (?*/-+l)

   -G, --generate-mode
          generate approximate mapfile from partial copy

   -H, --test-mode=<file>
          set map of good/bad blocks from given mapfile

   -i, --input-position=<bytes>
          starting position of domain in input file [0]

   -I, --verify-input-size
          verify input file size with size in mapfile

   -J, --verify-on-error
          reread latest good sector after every error

   -K, --skip-size=[<i>][,<max>]
          initial size to skip on read error [64 KiB]

   -L, --loose-domain
          accept an incomplete domain mapfile

   -m, --domain-mapfile=<file>
          restrict domain to finished blocks in file

   -M, --retrim
          mark all failed blocks as non-trimmed

   -n, --no-scrape
          skip the scraping phase

   -N, --no-trim
          skip the trimming phase

   -o, --output-position=<bytes>
          starting position in output file [ipos]

   -O, --reopen-on-error
          reopen input file after every read error

   -p, --preallocate
          preallocate space on disc for output file

   -P, --data-preview[=<lines>]
          show some lines of the latest data read [3]

   -q, --quiet
          suppress all messages

   -r, --retry-passes=<n>
          exit after <n> retry passes (-1=infinity) [0]

   -R, --reverse
          reverse the direction of all passes

   -s, --size=<bytes>
          maximum size of input data to be copied

   -S, --sparse
          use sparse writes for output file

   -t, --truncate
          truncate output file to zero size

   -T, --timeout=<interval>
          maximum time since last successful read

   -u, --unidirectional
          run all passes in the same direction

   -v, --verbose
          be verbose (a 2nd -v gives more)

   -w, --ignore-write-errors
          make fill mode ignore write errors

   -x, --extend-outfile=<bytes>
          extend outfile size to be at least this long

   -X, --exit-on-error
          exit after the first read error

   -y, --synchronous
          use synchronous writes for output file

   -Z, --max-read-rate=<bytes>
          maximum read rate in bytes/s

   --ask  ask for confirmation before starting the copy

   --cpass=<n>[,<n>]
          select what copying pass(es) to run

   --log-rates=<file>
          log rates and error sizes in file

   --log-reads=<file>
          log all read operations in file

   --pause=<interval>
          time to wait between passes [0]

   Numbers may be in decimal, hexadecimal or octal, and may be followed by
   a multiplier: s = sectors, k = 1000, Ki = 1024, M = 10^6,  Mi  =  2^20,
   etc...  Time intervals have the format 1[.5][smhd] or 1/2[smhd].

   Exit  status:  0  for a normal exit, 1 for environmental problems (file
   not found, invalid flags, I/O errors, etc), 2 to indicate a corrupt  or
   invalid input file, 3 for an internal consistency error (eg, bug) which
   caused ddrescue to panic.

REPORTING BUGS

   Report bugs to [email protected]
   Ddrescue home page: http://www.gnu.org/software/ddrescue/ddrescue.html
   General help using GNU software: http://www.gnu.org/gethelp

COPYRIGHT

   Copyright  2016 Antonio Diaz Diaz.  License GPLv2+: GNU GPL version  2
   or later <http://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

   The full documentation for ddrescue is maintained as a Texinfo  manual.
   If  the info and ddrescue programs are properly installed at your site,
   the command

          info ddrescue

   should give you access to the complete manual.

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