ddrescue Man page

Resume Wikipedia de Dd (Unix)

dd est une commande unix permettant de copier un fichier – avec ou sans conversion(s) au passage – en ne sélectionnant qu’une partie de données à copier. Il est particulièrement adapté à la copie sur des périphériques blocs tel que des disques durs ou des lecteurs CD-ROM.

DDRESCUE(1) User Commands DDRESCUE(1)

NAME

ddrescue – data recovery tool

SYNOPSIS

ddrescue [options] infile outfile [logfile]

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.

You should use a logfile unless you know what you are doing. If you
reboot, check the device names before restarting ddrescue. Do not 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=
minimum read rate of good areas in bytes/s

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

-b, –sector-size=
sector size of input device [default 512]

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

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

-C, –complete-only
do not read new data beyond logfile limits

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

-D, –synchronous
use synchronous writes for output file

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

-E, –max-error-rate=
maximum allowed rate of read errors per second

-f, –force
overwrite output device or partition

-F, –fill-mode=
fill given type blocks with infile data (?*/-+)

-G, –generate-mode
generate approximate logfile from partial copy

-H, –test-mode=
set map of good/bad blocks from given logile

-i, –input-position=
starting position of domain in input file [0]

-I, –verify-input-size
verify input file size with size in logfile

-K, –skip-size=[,] initial size to skip on read error [64 KiB]

-L, –loose-domain
accept an incomplete domain logfile

-m, –domain-logfile=
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=
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[=] show some lines of the latest data read [3]

-q, –quiet
suppress all messages

-r, –retry-passes=
exit after retry passes (-1=infinity) [0]

-R, –reverse
reverse the direction of all passes

-s, –size=
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=
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=
extend outfile size to be at least this long

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

-1, –log-rates=
log rates and error sizes in file

-2, –log-reads=
log all read operations in file

–ask ask for confirmation before starting the copy

–cpass=[,] select what copying pass(es) to run

–pause=
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 bug-ddrescue@gnu.org
Ddrescue home page: http://www.gnu.org/software/ddrescue/ddrescue.html
General help using GNU software: http://www.gnu.org/gethelp

COPRYRIGHT

Copyright © 2014 Antonio Diaz Diaz. License GPLv2+: GNU GPL version 2
or later
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.

ddrescue 1.19 October 2014 DDRESCUE(1)