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] [--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-directories]
[--nonmatching] [--preserve-modification-time] [--numeric-
uid-gid] [--rename] [--list] [--swap-bytes] [--swap]
[--dot] [--unconditional] [--verbose] [--block-
size=blocks] [--swap-halfwords] [--io-size=bytes]
[--pattern-file=file] [--format=format]
[--owner=[user][:.][group]] [--no-preserve-owner]
[--message=message] [--help] [--version] [pattern...] [<
archive]
cpio {-p|--pass-through} [-0adlmuvLV] [-R
[user][:.][group]] [--null] [--reset-access-time] [--make-
directories] [--link] [--preserve-modification-time]
[--unconditional] [--verbose] [--dot] [--dereference]
[--owner=[user][:.][group]] [--no-preserve-owner] [--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 pathname, owner, timestamps, and
access permissions. The archive can be another file on
the disk, a magnetic tape, or a pipe. cpio has three
operating 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
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CPIO(1L) CPIO(1L)
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 standard 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
architectures. 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 calculates 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 characters, 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 automatically 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 terminated 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.
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CPIO(1L) CPIO(1L)
-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 Use the old portable (ASCII) archive format.
-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 indicate a remote host name.
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CPIO(1L) CPIO(1L)
-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 systems 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).
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CPIO(1L) CPIO(1L)
-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.
--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).
-p, --pass-through
Run in copy-pass mode.
-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.
-s, --swap-bytes
In copy-in mode, swap the bytes of each halfword
(pair of bytes) in the files.
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CPIO(1L) CPIO(1L)
-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 table 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
correspond 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.
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