1DDRESCUE(1)                      User Commands                     DDRESCUE(1)
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NAME

6       ddrescue - data recovery tool
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SYNOPSIS

9       ddrescue [options] infile outfile [mapfile]
10

DESCRIPTION

12       GNU  ddrescue  is a data recovery tool. It copies data from one file or
13       block device (hard disc, cdrom, etc) to another, trying to  rescue  the
14       good parts first in case of read errors.
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16       Always  use a mapfile unless you know you won't need it. Without a map‐
17       file, ddrescue can't resume a rescue, only  reinitiate  it.   NOTE:  In
18       versions  of  ddrescue  prior to 1.20 the mapfile was called 'logfile'.
19       The format is the same; only the name has changed.
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21       If you reboot, check  the  device  names  before  restarting  ddrescue.
22       Don't use options '-F' or '-G' without reading the manual first.
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OPTIONS

25       -h, --help
26              display this help and exit
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28       -V, --version
29              output version information and exit
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31       -a, --min-read-rate=<bytes>
32              minimum read rate of good areas in bytes/s
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34       -A, --try-again
35              mark non-trimmed, non-scraped as non-tried
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37       -b, --sector-size=<bytes>
38              sector size of input device [default 512]
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40       -B, --binary-prefixes
41              show binary multipliers in numbers [SI]
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43       -c, --cluster-size=<sectors>
44              sectors to copy at a time [128]
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46       -C, --complete-only
47              don't read new data beyond mapfile limits
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49       -d, --idirect
50              use direct disc access for input file
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52       -D, --odirect
53              use direct disc access for output file
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55       -e, --max-bad-areas=[+]<n>
56              maximum number of [new] bad areas allowed
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58       -E, --max-error-rate=<bytes>
59              maximum allowed rate of read errors per second
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61       -f, --force
62              overwrite output device or partition
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64       -F, --fill-mode=<types>
65              fill blocks of given types with data (?*/-+l)
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67       -G, --generate-mode
68              generate approximate mapfile from partial copy
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70       -H, --test-mode=<file>
71              set map of good/bad blocks from given mapfile
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73       -i, --input-position=<bytes>
74              starting position of domain in input file [0]
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76       -I, --verify-input-size
77              verify input file size with size in mapfile
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79       -J, --verify-on-error
80              reread latest good sector after every error
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82       -K, --skip-size=[<i>][,<max>]
83              initial,maximum size to skip on read error
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85       -L, --loose-domain
86              accept an incomplete domain mapfile
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88       -m, --domain-mapfile=<file>
89              restrict domain to finished blocks in <file>
90
91       -M, --retrim
92              mark all failed blocks as non-trimmed
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94       -n, --no-scrape
95              skip the scraping phase
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97       -N, --no-trim
98              skip the trimming phase
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100       -o, --output-position=<bytes>
101              starting position in output file [ipos]
102
103       -O, --reopen-on-error
104              reopen input file after every read error
105
106       -p, --preallocate
107              preallocate space on disc for output file
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109       -P, --data-preview[=<lines>]
110              show some lines of the latest data read [3]
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112       -q, --quiet
113              suppress all messages
114
115       -r, --retry-passes=<n>
116              exit after <n> retry passes (-1=infinity) [0]
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118       -R, --reverse
119              reverse the direction of all passes
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121       -s, --size=<bytes>
122              maximum size of input data to be copied
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124       -S, --sparse
125              use sparse writes for output file
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127       -t, --truncate
128              truncate output file to zero size
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130       -T, --timeout=<interval>
131              maximum time since last successful read
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133       -u, --unidirectional
134              run all passes in the same direction
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136       -v, --verbose
137              be verbose (a 2nd -v gives more)
138
139       -w, --ignore-write-errors
140              make fill mode ignore write errors
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142       -x, --extend-outfile=<bytes>
143              extend outfile size to be at least this long
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145       -X, --max-read-errors=<n>
146              maximum number of read errors allowed
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148       -y, --synchronous
149              use synchronous writes for output file
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151       -Z, --max-read-rate=<bytes>
152              maximum read rate in bytes/s
153
154       --ask  ask for confirmation before starting the copy
155
156       --command-mode
157              execute commands from standard input
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159       --cpass=<n>[,<n>]
160              select what copying pass(es) to run
161
162       --delay-slow=<interval>
163              initial delay before checking slow reads [30]
164
165       --log-events=<file>
166              log significant events in <file>
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168       --log-rates=<file>
169              log rates and error sizes in <file>
170
171       --log-reads=<file>
172              log all read operations in <file>
173
174       --mapfile-interval=[i][,i]
175              save/sync mapfile at given interval [auto]
176
177       --max-slow-reads=<n>
178              maximum number of slow reads allowed
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180       --pause-on-error=<interval>
181              time to wait after each read error [0]
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183       --pause-on-pass=<interval>
184              time to wait between passes [0]
185
186       --reset-slow
187              reset slow reads if rate rises above min
188
189       --same-file
190              allow infile and outfile to be the same file
191
192       Numbers may be in decimal, hexadecimal or octal, and may be followed by
193       a multiplier: s = sectors, k = 1000, Ki = 1024, M = 10^6,  Mi  =  2^20,
194       etc...  Time intervals have the format 1[.5][smhd] or 1/2[smhd].
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196       Exit  status:  0  for a normal exit, 1 for environmental problems (file
197       not found, invalid flags, I/O errors, etc), 2 to indicate a corrupt  or
198       invalid input file, 3 for an internal consistency error (eg, bug) which
199       caused ddrescue to panic.
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REPORTING BUGS

202       Report bugs to bug-ddrescue@gnu.org
203       Ddrescue home page: http://www.gnu.org/software/ddrescue/ddrescue.html
204       General help using GNU software: http://www.gnu.org/gethelp
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207       Copyright © 2019 Antonio Diaz Diaz.  License GPLv2+: GNU GPL version  2
208       or later <http://gnu.org/licenses/gpl.html>
209       This  is  free  software:  you  are free to change and redistribute it.
210       There is NO WARRANTY, to the extent permitted by law.
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SEE ALSO

213       The full documentation for ddrescue is maintained as a Texinfo  manual.
214       If  the info and ddrescue programs are properly installed at your site,
215       the command
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217              info ddrescue
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219       should give you access to the complete manual.
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223ddrescue 1.24                    February 2019                     DDRESCUE(1)
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