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CPIO(1L) CPIO(1L)
NAME
cpio - copy files to and from archives
SYNOPSIS
cpio {-o|--create} [-0acvABLV] [-C bytes] [-H format] [-M message] [-O
[[user@]host:]archive] [-F [[user@]host:]archive]
[--file=[[user@]host:]archive] [--format=format] [--message=message]
[--null] [--reset-access-time] [--verbose] [--dot] [--append]
[--block-size=blocks] [--dereference] [--io-size=bytes] [--quiet]
[--force-local] [--rsh-command=command] [--help] [--version] < name-
list [> archive]
cpio {-i|--extract} [-bcdfmnrtsuvBSV] [-C bytes] [-E file] [-H format]
[-M message] [-R [user][:.][group]] [-I [[user@]host:]archive] [-F
[[user@]host:]archive] [--file=[[user@]host:]archive] [--make-directo-
ries] [--nonmatching] [--preserve-modification-time] [--numeric-uid-
gid] [--rename] [-t|--list] [--swap-bytes] [--swap] [--dot] [--uncon-
ditional] [--verbose] [--block-size=blocks] [--swap-halfwords] [--io-
size=bytes] [--pattern-file=file] [--format=format]
[--owner=[user][:.][group]] [--no-preserve-owner] [--message=message]
[--force-local] [--no-absolute-filenames] [--sparse] [--only-ver-
ify-crc] [--quiet] [--rsh-command=command] [--help] [--version] [pat-
tern...] [< archive]
cpio {-p|--pass-through} [-0adlmuvLV] [-R [user][:.][group]] [--null]
[--reset-access-time] [--make-directories] [--link] [--quiet] [--pre-
serve-modification-time] [--unconditional] [--verbose] [--dot]
[--dereference] [--owner=[user][:.][group]] [--no-preserve-owner]
[--sparse] [--help] [--version] destination-directory < name-list
DESCRIPTION
This manual page documents the GNU version of cpio. cpio copies files
into or out of a cpio or tar archive, which is a file that contains
other files plus information about them, such as their file name,
owner, timestamps, and access permissions. The archive can be another
file on the disk, a magnetic tape, or a pipe. cpio has three operat-
ing modes.
In copy-out mode, cpio copies files into an archive. It reads a list
of filenames, one per line, on the standard input, and writes the
archive onto the standard output. A typical way to generate the list
of filenames is with the find command; you should give find the -depth
option to minimize problems with permissions on directories that are
unwritable or not searchable.
In copy-in mode, cpio copies files out of an archive or lists the
archive contents. It reads the archive from the standard input. Any
non-option command line arguments are shell globbing patterns; only
files in the archive whose names match one or more of those patterns
are copied from the archive. Unlike in the shell, an initial '.' in a
filename does match a wildcard at the start of a pattern, and a '/' in
a filename can match wildcards. If no patterns are given, all files
are extracted.
In copy-pass mode, cpio copies files from one directory tree to
another, combining the copy-out and copy-in steps without actually
using an archive. It reads the list of files to copy from the stan-
dard input; the directory into which it will copy them is given as a
non-option argument.
cpio supports the following archive formats: binary, old ASCII, new
ASCII, crc, HPUX binary, HPUX old ASCII, old tar, and POSIX.1 tar.
The binary format is obsolete because it encodes information about the
files in a way that is not portable between different machine archi-
tectures. The old ASCII format is portable between different machine
architectures, but should not be used on file systems with more than
65536 i-nodes. The new ASCII format is portable between different
machine architectures and can be used on any size file system, but is
not supported by all versions of cpio; currently, it is only supported
by GNU and Unix System V R4. The crc format is like the new ASCII
format, but also contains a checksum for each file which cpio calcu-
lates when creating an archive and verifies when the file is extracted
from the archive. The HPUX formats are provided for compatibility
with HPUX's cpio which stores device files differently.
The tar format is provided for compatability with the tar program. It
can not be used to archive files with names longer than 100 charac-
ters, and can not be used to archive "special" (block or character
devices) files. The POSIX.1 tar format can not be used to archive
files with names longer than 255 characters (less unless they have a
"/" in just the right place).
By default, cpio creates binary format archives, for compatibility
with older cpio programs. When extracting from archives, cpio auto-
matically recognizes which kind of archive it is reading and can read
archives created on machines with a different byte-order.
Some of the options to cpio apply only to certain operating modes; see
the SYNOPSIS section for a list of which options are allowed in which
modes.
OPTIONS
-0, --null
In copy-out and copy-pass modes, read a list of filenames ter-
minated by a null character instead of a newline, so that files
whose names contain newlines can be archived. GNU find is one
way to produce a list of null-terminated filenames.
-a, --reset-access-time
Reset the access times of files after reading them, so that it
does not look like they have just been read.
-A, --append
Append to an existing archive. Only works in copy-out mode.
The archive must be a disk file specified with the -O or -F
(--file) option.
-b, --swap
In copy-in mode, swap both halfwords of words and bytes of
halfwords in the data. Equivalent to -sS. Use this option to
convert 32-bit integers between big-endian and little-endian
machines.
-B Set the I/O block size to 5120 bytes. Initially the block size
is 512 bytes.
--block-size=BLOCK-SIZE
Set the I/O block size to BLOCK-SIZE * 512 bytes.
-c Identical to "-H newc", use the new (SVR4) portable format. If
you wish the old portable (ASCII) archive format, use "-H odc"
instead.
-C IO-SIZE, --io-size=IO-SIZE
Set the I/O block size to IO-SIZE bytes.
-d, --make-directories
Create leading directories where needed.
-E FILE, --pattern-file=FILE
In copy-in mode, read additional patterns specifying filenames
to extract or list from FILE. The lines of FILE are treated as
if they had been non-option arguments to cpio.
-f, --nonmatching
Only copy files that do not match any of the given patterns.
-F, --file=archive
Archive filename to use instead of standard input or output.
To use a tape drive on another machine as the archive, use a
filename that starts with 'HOSTNAME:'. The hostname can be
preceded by a username and an '@' to access the remote tape
drive as that user, if you have permission to do so (typically
an entry in that user's '~/.rhosts' file).
--force-local
With -F, -I, or -O, take the archive file name to be a local
file even if it contains a colon, which would ordinarily indi-
cate a remote host name.
-H FORMAT, --format=FORMAT
Use archive format FORMAT. The valid formats are listed below;
the same names are also recognized in all-caps. The default in
copy-in mode is to automatically detect the archive format, and
in copy-out mode is "bin".
bin The obsolete binary format.
odc The old (POSIX.1) portable format.
newc The new (SVR4) portable format, which supports file sys-
tems having more than 65536 i-nodes.
crc The new (SVR4) portable format with a checksum added.
tar The old tar format.
ustar The POSIX.1 tar format. Also recognizes GNU tar
archives, which are similar but not identical.
hpbin The obsolete binary format used by HPUX's cpio (which
stores device files differently).
hpodc The portable format used by HPUX's cpio (which stores
device files differently).
-i, --extract
Run in copy-in mode.
-I archive
Archive filename to use instead of standard input. To use a
tape drive on another machine as the archive, use a filename
that starts with 'HOSTNAME:'. The hostname can be preceded by
a username and an '@' to access the remote tape drive as that
user, if you have permission to do so (typically an entry in
that user's '~/.rhosts' file).
-k Ignored; for compatibility with other versions of cpio.
-l, --link
Link files instead of copying them, when possible.
-L, --dereference
Dereference symbolic links (copy the files that they point to
instead of copying the links).
-m, --preserve-modification-time
Retain previous file modification times when creating files.
-M MESSAGE, --message=MESSAGE
Print MESSAGE when the end of a volume of the backup media
(such as a tape or a floppy disk) is reached, to prompt the
user to insert a new volume. If MESSAGE contains the string
"%d", it is replaced by the current volume number (starting at
1).
-n, --numeric-uid-gid
In the verbose table of contents listing, show numeric UID and
GID instead of translating them into names. Also extracts tar
archives using the numeric UID and GID instead of the
user/group names. (cpio archives are always extracted using
the numeric UID and GID.)
--no-absolute-filenames
In copy-in mode, create all files relative to the current
directory, even if they have an absolute file name in the
archive.
--no-preserve-owner
In copy-in mode and copy-pass mode, do not change the ownership
of the files; leave them owned by the user extracting them.
This is the default for non-root users, so that users on System
V don't inadvertantly give away files.
-o, --create
Run in copy-out mode.
-O archive
Archive filename to use instead of standard output. To use a
tape drive on another machine as the archive, use a filename
that starts with 'HOSTNAME:'. The hostname can be preceded by
a username and an '@' to access the remote tape drive as that
user, if you have permission to do so (typically an entry in
that user's '~/.rhosts' file).
--only-verify-crc
When reading a CRC format archive in copy-in mode, only verify
the CRC's of each file in the archive, don't actually extract
the files.
-p, --pass-through
Run in copy-pass mode.
--quiet
Do not print the number of blocks copied.
-r, --rename
Interactively rename files.
-R [user][:.][group], --owner [user][:.][group]
In copy-out and copy-pass modes, set the ownership of all files
created to the specified user and/or group. Either the user or
the group, or both, must be present. If the group is omitted
but the ":" or "." separator is given, use the given user's
login group. Only the super-user can change files' ownership.
--rsh-command=COMMAND
Notifies mt that it should use COMMAND to communicate with
remote devices instead of /usr/bin/ssh or /usr/bin/rsh.
--sparse
In copy-in and copy-pass modes, write files with large blocks
of zeros as sparse files.
-s, --swap-bytes
In copy-in mode, swap the bytes of each halfword (pair of
bytes) in the files.
-S, --swap-halfwords
In copy-in mode, swap the halfwords of each word (4 bytes) in
the files.
-t, --list
Print a table of contents of the input.
-u, --unconditional
Replace all files, without asking whether to replace existing
newer files with older files.
-v, --verbose
List the files processed, or with -t, give an 'ls -l' style ta-
ble of contents listing. In a verbose table of contents of a
ustar archive, user and group names in the archive that do not
exist on the local system are replaced by the names that corre-
spond locally to the numeric UID and GID stored in the archive.
-V --dot
Print a "." for each file processed.
--version
Print the cpio program version number and exit.
CPIO(1L)
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