1CPIO(1L) CPIO(1L)
2
6 cpio - copy files to and from archives
7
9 Copy-out mode
10 In copy-out mode, cpio copies files into an archive. It reads a list
12 of filenames, one per line, on the standard input, and writes the ar‐
13 chive onto the standard output. A typical way to generate the list of
14 filenames is with the find command; you should give find the -depth
15 option to minimize problems with permissions on directories that are
16 unreadable. see Options.
17 cpio {-o|--create} [-0acvABLV] [-C bytes] [-H format] [-M message] [-O
19 [[user@]host:]archive] [-F [[user@]host:]archive]
20 [--file=[[user@]host:]archive] [--format=format] [--message=mes‐
21 sage][--null] [--reset-access-time] [--verbose] [--dot] [--append]
22 [--block-size=blocks] [--dereference] [--io-size=bytes] [--rsh-com‐
23 mand=command] [--help] [--version] < name-list [> archive]
24 Copy-in mode
26 In copy-in mode, cpio copies files out of an archive or lists the ar‐
28 chive contents. It reads the archive from the standard input. Any
29 non-option command line arguments are shell globbing patterns; only
30 files in the archive whose names match one or more of those patterns
31 are copied from the archive. Unlike in the shell, an initial `.' in a
32 filename does match a wildcard at the start of a pattern, and a `/' in
33 a filename can match wildcards. If no patterns are given, all files
34 are extracted. see Options.
35 cpio {-i|--extract} [-bcdfmnrtsuvBSV] [-C bytes] [-E file] [-H format]
37 [-M message] [-R [user][:.][group]] [-I [[user@]host:]archive] [-F
38 [[user@]host:]archive] [--file=[[user@]host:]archive] [--make-directo‐
39 ries] [--nonmatching] [--preserve-modification-time]
40 [--numeric-uid-gid] [--rename] [--list] [--swap-bytes] [--swap] [--dot]
41 [--unconditional] [--verbose] [--block-size=blocks] [--swap-halfwords]
42 [--io-size=bytes] [--pattern-file=file] [--format=format]
43 [--owner=[user][:.][group]] [--no-preserve-owner] [--message=message]
44 [--help] [--version] [--absolute-filenames] [--sparse] [-only-ver‐
45 ify-crc] [-quiet] [--rsh-command=command] [pattern...] [< archive]
46 Copy-pass mode
48 In copy-pass mode, cpio copies files from one directory tree to
50 another, combining the copy-out and copy-in steps without actually
51 using an archive. It reads the list of files to copy from the standard
52 input; the directory into which it will copy them is given as a non-
53 option argument. see Options.
54 cpio {-p|--pass-through} [-0adlmuvLV] [-R [user][:.][group]] [--null]
56 [--reset-access-time] [--make-directories] [--link] [--preserve-modifi‐
57 cation-time] [--unconditional] [--verbose] [--dot] [--dereference]
58 [--owner=[user][:.][group]] [--sparse] [--no-preserve-owner] [--help]
59 [--version] destination-directory < name-list
60
62 GNU cpio is a tool for creating and extracting archives, or copying
63 files from one place to another. It handles a number of cpio formats
64 as well as reading and writing tar files.
65 Following archive formats are supported: binary, old ASCII, new ASCII,
67 crc, HPUX binary, HPUX old ASCII, old tar, and POSIX.1 tar. The tar
68 format is provided for compatability with the tar program. By default,
69 cpio creates binary format archives, for compatibility with older cpio
70 programs. When extracting from archives, cpio automatically recognizes
71 which kind of archive it is reading and can read archives created on
72 machines with a different byte-order.
73
75 `-0, --null' Read a list of filenames terminated by a null character,
76 instead of a newline, so that files whose names contain newlines can be
77 archived. GNU find is one way to produce a list of null-terminated
78 filenames. This option may be used in copy-out and copy-pass modes.
79 `-a, --reset-access-time' Reset the access times of files after reading
81 them, so that it does not look like they have just been read.
82 `-A, --append' Append to an existing archive. Only works in copy-out
84 mode. The archive must be a disk file specified with the -O or -F
85 (-file) option.
86 `-b, --swap' Swap both halfwords of words and bytes of halfwords in the
88 data. Equivalent to -sS. This option may be used in copy-in mode.
89 Use this option to convert 32-bit integers between big-endian and lit‐
90 tle-endian machines.
91 `-B' Set the I/O block size to 5120 bytes. Initially the block size is
93 512 bytes.
94 `--block-size=BLOCK-SIZE' Set the I/O block size to BLOCK-SIZE * 512
96 bytes.
97 `-c' Identical to -H newc, use the new (SVR4) portable format. If you
99 wish the old portable (ASCII) archive format, use -H odc instead.
100 `-C IO-SIZE, --io-size=IO-SIZE' Set the I/O block size to IO-SIZE
102 bytes.
103 `-d, --make-directories' Create leading directories where needed.
105 `-E FILE, --pattern-file=FILE' Read additional patterns specifying
107 filenames to extract or list from FILE. The lines of FILE are treated
108 as if they had been non-option arguments to cpio. This option is used
109 in copy-in mode,
110 `-f, --nonmatching' Only copy files that do not match any of the given
112 patterns.
113 `-F, --file=archive' Archive filename to use instead of standard input
115 or output. To use a tape drive on another machine as the archive, use
116 a filename that starts with `HOSTNAME:'. The hostname can be preceded
117 by a username and an `@' to access the remote tape drive as that user,
118 if you have permission to do so (typically an entry in that user's
119 `~/.rhosts' file).
120 `--force-local' With -F, -I, or -O, take the archive file name to be a
122 local file even if it contains a colon, which would ordinarily indicate
123 a remote host name.
124 `-H FORMAT, --format=FORMAT' Use archive format FORMAT. The valid for‐
126 mats are listed below; the same names are also recognized in all-caps.
127 The default in copy-in mode is to automatically detect the archive for‐
128 mat, and in copy-out mode is `bin'.
129 `bin' The obsolete binary format.
131 `odc' The old (POSIX.1) portable format.
133 `newc' The new (SVR4) portable format, which supports file systems hav‐
135 ing more than 65536 i-nodes.
136 `crc' The new (SVR4) portable format with a checksum added.
138 `tar' The old tar format.
140 `ustar' The POSIX.1 tar format. Also recognizes GNU tar archives,
142 which are similar but not identical.
143 `hpbin' The obsolete binary format used by HPUX's cpio (which stores
145 device files differently).
146 `hpodc' The portable format used by HPUX's cpio (which stores device
148 files differently).
149 `-i, --extract' Run in copy-in mode. see Copy-in mode.
151 `-I archive' Archive filename to use instead of standard input. To use
153 a tape drive on another machine as the archive, use a filename that
154 starts with `HOSTNAME:'. The hostname can be preceded by a username
155 and an `@' to access the remote tape drive as that user, if you have
156 permission to do so (typically an entry in that user's `~/.rhosts'
157 file).
158 `-k' Ignored; for compatibility with other versions of cpio.
160 `-l, --link' Link files instead of copying them, when possible.
162 `-L, --dereference' Copy the file that a symbolic link points to,
164 rather than the symbolic link itself.
165 `-m, --preserve-modification-time' Retain previous file modification
167 times when creating files.
168 `-M MESSAGE, --message=MESSAGE' Print MESSAGE when the end of a volume
170 of the backup media (such as a tape or a floppy disk) is reached, to
171 prompt the user to insert a new volume. If MESSAGE contains the string
172 %d, it is replaced by the current volume number (starting at 1).
173 `-n, --numeric-uid-gid' Show numeric UID and GID instead of translating
175 them into names when using the `--verbose option'.
176 `--absolute-filenames' Do not strip leading file name components that
178 contain .. and leading slashes from file names in copy-in mode
179 `--no-preserve-owner' Do not change the ownership of the files; leave
181 them owned by the user extracting them. This is the default for non-
182 root users, so that users on System V don't inadvertantly give away
183 files. This option can be used in copy-in mode and copy-pass mode
184 `-o, --create' Run in copy-out mode. see Copy-out mode.
186 `-O archive' Archive filename to use instead of standard output. To
188 use a tape drive on another machine as the archive, use a filename that
189 starts with `HOSTNAME:'. The hostname can be preceded by a username
190 and an `@' to access the remote tape drive as that user, if you have
191 permission to do so (typically an entry in that user's `~/.rhosts'
192 file).
193 `--only-verify-crc' Verify the CRC's of each file in the archive, when
195 reading a CRC format archive. Don't actually extract the files.
196 `-p, --pass-through' Run in copy-pass mode. see Copy-pass mode.
198 `--quiet' Do not print the number of blocks copied.
200 `-r, --rename' Interactively rename files.
202 `-R [user][:.][group], --owner [user][:.][group]' Set the ownership of
204 all files created to the specified user and/or group in copy-out and
205 copy-pass modes. Either the user, the group, or both, must be present.
206 If the group is omitted but the : or . separator is given, use the
207 given user's login group. Only the super-user can change files' owner‐
208 ship.
209 `--rsh-command=COMMAND' Notifies cpio that is should use COMMAND to
211 communicate with remote devices.
212 `-s, --swap-bytes' Swap the bytes of each halfword (pair of bytes) in
214 the files.This option can be used in copy-in mode.
215 `-S, --swap-halfwords' Swap the halfwords of each word (4 bytes) in the
217 files. This option may be used in copy-in mode.
218 `--sparse' Write files with large blocks of zeros as sparse files.
220 This option is used in copy-in and copy-pass modes.
221 `-t, --list' Print a table of contents of the input.
223 `-u, --unconditional' Replace all files, without asking whether to
225 replace existing newer files with older files.
226 `-v, --verbose' List the files processed, or with `-t', give an `ls -l'
228 style table of contents listing. In a verbose table of contents of a
229 ustar archive, user and group names in the archive that do not exist on
230 the local system are replaced by the names that correspond locally to
231 the numeric UID and GID stored in the archive.
232 `-V --dot' Print a `.' for each file processed.
234 `--version' Print the cpio program version number and exit.
236
238 When creating an archive, cpio takes the list of files to be processed
239 from the standard input, and then sends the archive to the standard
240 output, or to the device defined by the `-F' option. Usually find or
241 ls is used to provide this list to the standard input. In the follow‐
242 ing example you can see the possibilities for archiving the contents of
243 a single directory.
244 % ls | cpio -ov > directory.cpio
246 The `-o' option creates the archive, and the `-v' option prints the
248 names of the files archived as they are added. Notice that the options
249 can be put together after a single `-' or can be placed separately on
250 the command line. The `>' redirects the cpio output to the file
251 `directory.cpio'.
252 If you wanted to archive an entire directory tree, the find command can
254 provide the file list to cpio:
255 % find . -print -depth | cpio -ov > tree.cpio
257 This will take all the files in the current directory, the directories
259 below and place them in the archive tree.cpio. Again the `-o' creates
260 an archive, and the `-v' option shows you the name of the files as they
261 are archived. see Copy-out mode. Using the `.' in the find statement
262 will give you more flexibility when doing restores, as it will save
263 file names with a relative path vice a hard wired, absolute path. The
264 `-depth' option forces `find' to print of the entries in a directory
265 before printing the directory itself. This limits the effects of
266 restrictive directory permissions by printing the directory entries in
267 a directory before the directory name itself.
268 Extracting an archive requires a bit more thought because cpio will not
270 create directories by default. Another characteristic, is it will not
271 overwrite existing files unless you tell it to.
272 % cpio -iv < directory.cpio
274 This will retrieve the files archived in the file directory.cpio and
276 place them in the present directory. The `-i' option extracts the ar‐
277 chive and the `-v' shows the file names as they are extracted. If you
278 are dealing with an archived directory tree, you need to use the `-d'
279 option to create directories as necessary, something like:
280 % cpio -idv < tree.cpio
282 This will take the contents of the archive tree.cpio and extract it to
284 the current directory. If you try to extract the files on top of files
285 of the same name that already exist (and have the same or later modifi‐
286 cation time) cpio will not extract the file unless told to do so by the
287 -u option. see Copy-in mode.
288 In copy-pass mode, cpio copies files from one directory tree to
290 another, combining the copy-out and copy-in steps without actually
291 using an archive. It reads the list of files to copy from the standard
292 input; the directory into which it will copy them is given as a non-
293 option argument. see Copy-pass mode.
294 % find . -depth -print0 | cpio --null -pvd new-dir
296 The example shows copying the files of the present directory, and sub-
298 directories to a new directory called new-dir. Some new options are
299 the `-print0' available with GNU find, combined with the `--null'
300 option of cpio. These two options act together to send file names
301 between find and cpio, even if special characters are embedded in the
302 file names. Another is `-p', which tells cpio to pass the files it
303 finds to the directory `new-dir'.
304
307 The GNU folks, in general, abhor man pages, and create info documents
308 instead. The maintainer of cpio falls into this category. Thus this
309 man page may not be complete, nor current, and was included in the Red
310 Hat CVS tree because man is a great tool :).
311
313 Please report bugs via https://bugzilla.redhat.com.
314
316 The full documentation for cpio is maintained as a Texinfo manual. If
317 the info and cpio programs are properly installed at your site, the
318 command
319 info cpio
321 should give you access to the complete manual. The online copy of the
323 documentation is available at the following address:
324 http://www.gnu.org/software/cpio/manual
326 CPIO(1L)