1DC3DD(1)                         User Commands                        DC3DD(1)
2
3
4

NAME

6       dc3dd - convert and copy a file
7

SYNOPSIS

9       dc3dd [OPERAND]...
10       dc3dd OPTION
11

DESCRIPTION

13       Copy a file, converting and formatting according to the operands.
14
15       bs=BYTES
16              force ibs=BYTES and obs=BYTES
17
18       cbs=BYTES
19              convert BYTES bytes at a time
20
21       conv=CONVS
22              convert the file as per the comma separated symbol list
23
24       count=SECTORS
25              copy only SECTORS input sectors
26
27       ibs=BYTES
28              read  BYTES  bytes at a time (must be a multiple of input sector
29              size)
30
31       if=FILE
32              read from FILE instead of stdin
33
34       ifjoin=BASE.FMT
35              read from split files with name BASE and splitformat FMT
36
37       iflag=FLAGS
38              read as per the comma separated symbol list
39
40       pattern=HEX
41              write HEX to every byte of the output
42
43       textpattern=TEXT
44              write the string TEXT repeatedly to the output
45
46       obs=BYTES
47              write BYTES bytes at a time
48
49       of=FILE
50              write to FILE instead of stdout
51
52       of:=COMMAND
53              pipe output to the given command
54
55       oflag=FLAGS
56              write as per the comma separated symbol list
57
58       wipe=FILE
59              wipe device FILE with zeros (or specify pattern/textpattern)
60
61       seek=SECTORS
62              skip SECTORS input sectors at start of output
63
64       skip=SECTORS
65              skip SECTORS input sectors at start of input
66
67       status=noxfer
68              suppress transfer statistics
69
70       split=BYTES
71              split the output into pieces of size BYTES
72
73       splitformat=FMT
74              create extensions for split pieces using FMT
75
76              Extensions can be numerical starting at zero, numerical starting
77              at  one, or alphabetical.  These options are selected by using a
78              series of zeros, ones, or a's, respectively. The number of char‐
79              acters  used indicates the desired length of the extensions. For
80              example, splitformat=1111  indicates  four  character  numerical
81              extensions starting with 0001.
82
83       progress=on
84              displays a progress meter
85
86       progresscount=NUM
87              number of blocks processed between each progress update
88
89       sizeprobe=on
90              estimates size of input file for use with status
91
92       hash=ALGORITHM
93              computes ALGORITHM hashes of the input data
94
95       hashconv=WHEN
96              determines  when  data  should be hashed, either before or after
97              conversions
98
99       hashwindow=BYTES
100              number of bytes for piecewise hashing
101
102       hashlog=FILE
103              appends piecewise hashes to the log file
104
105       errlog=FILE
106              appends errors to the log file
107
108       log=FILE
109              appends hashes and errors to the same file
110
111       errors=group
112              group read errors together
113
114       vf=FILE
115              verify the input against FILE
116
117              vfjoin=BASE.FMT verify the input against split files  with  name
118              BASE  and  splitformat  FMT verifylog=FILE  write the results of
119              the verify to the given file
120
121       ALGORITHM can be a comma separated  list  of  md5,  sha1,  sha256,  and
122       sha512
123
124       BLOCKS  and  BYTES may be followed by the following multiplicative suf‐
125       fixes: xM M, c 1, w 2,  b  512,  kB  1000,  K  1024,  MB  1000*1000,  M
126       1024*1024,  GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E,
127       Z, Y.
128
129       Each CONV symbol may be:
130
131       ascii  from EBCDIC to ASCII
132
133       ebcdic from ASCII to EBCDIC
134
135       ibm    from ASCII to alternate EBCDIC
136
137       block  pad newline-terminated records with spaces to cbs-size
138
139       unblock
140              replace trailing spaces in cbs-size records with newline
141
142       lcase  change upper case to lower case
143
144       nocreat
145              do not create the output file
146
147       excl   fail if the output file already exists
148
149       notrunc
150              do not truncate the output file
151
152       ucase  change lower case to upper case
153
154       swab   swap every pair of input bytes
155
156       noerror
157              continue after read errors
158
159       sync   pad every input block with NULs  to  ibs-size;  when  used  with
160              block or unblock, pad with spaces rather than NULs
161
162       fdatasync
163              physically write output file data before finishing
164
165       fsync  likewise, but also write metadata
166
167       Each FLAG symbol may be:
168
169       append append  mode  (makes  sense  only  for output; conv=notrunc sug‐
170              gested)
171
172       direct use direct I/O for data
173
174              directory fail unless a directory dsync     use synchronized I/O
175              for data sync      likewise, but also for metadata nonblock  use
176              non-blocking I/O noatime   do  not  update  access  time  noctty
177              do  not  assign  controlling terminal from file nofollow  do not
178              follow symlinks
179
180       Sending a USR1 signal to a running `dd' process makes it print I/O sta‐
181       tistics to standard error and then resume copying.
182
183              $ dd if=/dev/zero of=/dev/null& pid=$!
184              $ kill -USR1 $pid; sleep 1; kill $pid
185
186              18335302+0  sectors  in  18335302+0 sectors out 9387674624 bytes
187              (9.4 GB) copied, 34.6279 seconds, 271 MB/s
188
189       Options are:
190
191       --help display this help and exit
192
193       --version
194              output version information and exit
195
196       --flags
197              display compile-time flags
198

AUTHOR

200       Written by Paul Rubin, David MacKenzie, Stuart Kemp,  and  patched  for
201       DC3 by Jesse Kornblum and Andrew Medico.
202

REPORTING BUGS

204       Report bugs to <dc3dd@dc3.mil>.
205

COPYRIGHT

207       Copyright  ©  2008  Free Software Foundation, Inc.  License GPLv3+: GNU
208       GPL version 3 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.
211

SEE ALSO

213       The full documentation for dc3dd is maintained as a Texinfo manual.  If
214       the info and dc3dd programs are properly installed at  your  site,  the
215       command
216
217              info dc3dd
218
219       should give you access to the complete manual.
220
221
222
223dc3dd 6.12.3                      August 2009                         DC3DD(1)