.TH CPIO 1L \" -*- nroff -*-
.SH NAME
cpio \- copy files to and from archives
.SH __WARNING__
.PP
The cpio utility is considered LEGACY based on POSIX specification.  Users are
encouraged to use other archiving tools for archive creation.

If you decided to use cpio, you should almost always force cpio to use the
ustar format in copy-out mode by the -H option (cpio -o -H ustar).  This is
because the ustar format is well defined in POSIX specification and thus
readable by wide range of other archiving tools (including tar e.g.).

By default, GNU cpio uses (for historical reasons) the very old binary format
('bin') which has significant problems nowadays, e.g. with storing big inode
numbers (see the Red Hat bug #952313).

Note also that these days the modern 'pax' archive format should be considered
as the default -- but this format is not implemented in GNU cpio.  You should,
again, consider using other archivers (e.g. 'tar --format=pax').

.SH SYNOPSIS
\&\fBCopy-out mode\fR
.PP
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
unreadable.  see \*(lqOptions\*(rq.
.PP
.B cpio
{\-o|\-\-create} [\-0acvABLV] [\-C bytes] [\-H format]
[\-M message] [\-O [[user@]host:]archive] [\-F [[user@]host:]archive]
[\-\-file=[[user@]host:]archive] [\-\-format=format] [\-\-warning=FLAG]
[\-\-message=message][\-\-null] [\-\-reset\-access\-time] [\-\-verbose]
[\-\-dot] [\-\-append] [\-\-block\-size=blocks] [\-\-dereference]
[\-\-io\-size=bytes] [\-\-rsh\-command=command]  [\-\-license] [\-\-usage]
[\-\-help] [\-\-version]
< name-list [> archive]
.PP
\&\fBCopy-in mode\fR
.PP
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 `\fB.\fR' in a
filename does match a wildcard at the start of a pattern, and a `\fB/\fR' in a
filename can match wildcards.  If no patterns are given, all files are
extracted.  see \*(lqOptions\*(rq.
.PP
.B 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] [\-t|\-\-list] [\-\-swap-bytes] [\-\-swap]
[\-\-dot] [\-\-warning=FLAG] [\-\-unconditional] [\-\-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] [\-\-absolute\-filenames]
[\-\-sparse] [\-\-only\-verify\-crc] [\-\-to\-stdout] [\-\-quiet]
[\-\-rsh-command=command] [\-\-license] [\-\-usage] [\-\-help]
[\-\-version] [pattern...] [< archive]
.PP
\&\fBCopy-pass mode\fR
.PP
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.  see \*(lqOptions\*(rq.
.PP
.B cpio
{\-p|\-\-pass-through} [\-0adlmuvLV] [\-R [user][:.][group]]
[\-\-null] [\-\-reset-access-time] [\-\-make-directories] [\-\-link] [\-\-quiet]
[\-\-preserve-modification-time] [\-\-unconditional] [\-\-verbose] [\-\-dot]
[\-\-warning=FLAG] [\-\-dereference] [\-\-owner=[user][:.][group]]
[\-\-no-preserve-owner] [\-\-sparse]  [\-\-license] [\-\-usage] [\-\-help]
[\-\-version] destination-directory < name-list
.PP
.SH DESCRIPTION
GNU cpio is a tool for creating and extracting archives, or copying
files from one place to another.  It handles a number of cpio formats as
well as reading and writing tar files.
.PP
Following archive formats are supported: binary, old ASCII, new ASCII, crc, HPUX binary, HPUX old
ASCII, old tar, and POSIX.1 tar.  The tar format is provided for compatibility with the tar program. 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.
.PP
.SH OPTIONS
.TP
`\fB\-0, \-\-null\fR'
Read a list of filenames terminated by a null character, instead
of a newline, so that files whose names contain newlines can be
archived.  \s-1GNU\s0 find is one way to produce a list of
null-terminated filenames.  This option may be used in copy-out
and copy-pass modes.
.TP
`\fB\-a, \-\-reset\-access\-time\fR'
Reset the access times of files after reading them, so that it
does not look like they have just been read.
.TP
`\fB\-A, \-\-append\fR'
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.
.TP
`\fB\-b, \-\-swap\fR'
Swap both halfwords of words and bytes of halfwords in the data.
Equivalent to \-sS.  This option may be used in copy-in mode.  Use
this option to convert 32\-bit integers between big-endian and
little-endian machines.
.TP
`\fB\-B\fR'
Set the I/O block size to 5120 bytes.  Initially the block size is
512 bytes.
.TP
`\fB\-\-block\-size=BLOCK\-SIZE\fR'
Set the I/O block size to BLOCK-SIZE * 512 bytes.
.TP
`\fB\-c\fR'
Identical to \*(lq\-H newc\*(rq, use the new (\s-1SVR4\s0) portable format.
If you wish the old portable (\s-1ASCII\s0) archive format, use \*(lq\-H odc\*(rq instead.
.TP
`\fB\-C \s-1IO\-SIZE\s0, \-\-io\-size=IO\-SIZE\fR'
Set the I/O block size to IO-SIZE bytes.
.TP
`\fB\-d, \-\-make\-directories\fR'
Create leading directories where needed.
.TP
`\fB\-E \s-1FILE\s0, \-\-pattern\-file=FILE\fR'
Read additional patterns specifying filenames to extract or list
from \s-1FILE\s0.  The lines of \s-1FILE\s0 are treated as if they had been
non-option arguments to cpio.  This option is used in copy-in mode,
.TP
`\fB\-f, \-\-nonmatching\fR'
Only copy files that do not match any of the given patterns.
.TP
`\fB\-F, \-\-file=archive\fR'
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 `\fB\s-1HOSTNAME:\s0\fR'.  The hostname can be preceded by a
username and an `\fB@\fR' to access the remote tape drive as that user,
if you have permission to do so (typically an entry in that user's
`\fB~/.rhosts\fR' file).
.TP
`\fB\-\-force\-local\fR'
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.
.TP
`\fB\-H \s-1FORMAT\s0, \-\-format=FORMAT\fR'
Use archive format \s-1FORMAT\s0.  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 `\fBbin\fR'.
.TP
`bin'
The obsolete binary format.
.TP
`odc'
The old (\s-1POSIX\s0.1) portable format.
.TP
`newc'
The new (\s-1SVR4\s0) portable format, which supports file systems
having more than 65536 i\-nodes.
.TP
`crc'
The new (\s-1SVR4\s0) portable format with a checksum (Sum32) added.
.TP
`tar'
The old tar format.
.TP
`ustar'
The \s-1POSIX\s0.1 tar format.  Also recognizes \s-1GNU\s0 tar archives,
which are similar but not identical.
.TP
`hpbin'
The obsolete binary format used by \s-1HPUX\s0's cpio (which stores
device files differently).
.TP
`hpodc'
The portable format used by \s-1HPUX\s0's cpio (which stores device
files differently).
.TP
`\fB\-i, \-\-extract\fR'
Run in copy-in mode.  see \*(lqCopy\-in mode\*(rq.
.TP
`\fB\-I archive\fR'
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 `\fB\s-1HOSTNAME:\s0\fR'.  The hostname can be preceded by a
username and an `\fB@\fR' to access the remote tape drive as that user,
if you have permission to do so (typically an entry in that user's
`\fB~/.rhosts\fR' file).
.TP
`\fB\-k\fR'
Ignored; for compatibility with other versions of cpio.
.TP
`\fB\-l, \-\-link\fR'
Link files instead of copying them, when possible.
.TP
`\fB\-L, \-\-dereference\fR'
Copy the file that a symbolic link points to, rather than the
symbolic link itself.
.TP
`\fB\-m, \-\-preserve\-modification\-time\fR'
Retain previous file modification times when creating files.
.TP
`\fB\-M \s-1MESSAGE\s0, \-\-message=MESSAGE\fR'
Print \s-1MESSAGE\s0 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 \s-1MESSAGE\s0 contains the string \*(lq%d\*(rq, it is
replaced by the current volume number (starting at 1).
.TP
`\fB\-n, \-\-numeric\-uid\-gid\fR'
Show numeric \s-1UID\s0 and \s-1GID\s0 instead of translating them into names
when using the `\fB\-\-verbose option\fR'.
.TP
`\fB\-\-no\-absolute\-filenames\fR'
Create all files relative to the current directory in copy-in
mode, even if they have an absolute file name in the archive.
.TP
`\fB\-\-absolute\-filenames\fR' (default)
Do not strip leading file name components that contain \*(lq..\*(rq
and leading slashes from file names in copy-in mode
.TP
`\fB\-\-no\-preserve\-owner\fR'
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 inadvertently give away files.  This
option can be used in copy-in mode and copy-pass mode
.TP
`\fB\-o, \-\-create\fR'
Run in copy-out mode.  see \*(lqCopy\-out mode\*(rq.
.TP
`\fB\-O archive\fR'
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 `\fB\s-1HOSTNAME:\s0\fR'.  The hostname can be preceded by a
username and an `\fB@\fR' to access the remote tape drive as that user,
if you have permission to do so (typically an entry in that user's
`\fB~/.rhosts\fR' file).
.TP
`\fB\-\-only\-verify\-crc\fR'
Verify the \s-1Sum32 checksum\s0's of each file in the archive, when reading a
\s-1crc\s0 format archive. Don't actually extract the files.
.TP
`\fB\-p, \-\-pass\-through\fR'
Run in copy-pass mode.  see \*(lqCopy\-pass mode\*(rq.
.TP
`\fB\-\-quiet\fR'
Do not print the number of blocks copied.
.TP
`\fB\-r, \-\-rename\fR'
Interactively rename files.
.TP
`\fB\-R [user][:.][group], \-\-owner [user][:.][group]\fR'
Set the ownership of all files created to the specified user and/or
group in copy-out and copy-pass modes.  Either the user, the
group, or both, must be present.  If the group is omitted but the
\&\*(lq:\*(rq or \*(lq.\*(rq separator is given, use the given user's login group.
Only the super-user can change files' ownership.
.TP
`\fB\-\-rsh\-command=COMMAND\fR'
Notifies cpio that is should use \s-1COMMAND\s0 to communicate with remote
devices.
.TP
`\fB\-s, \-\-swap\-bytes\fR'
Swap the bytes of each halfword (pair of bytes) in the files.This
option can be used in copy-in mode.
.TP
`\fB\-S, \-\-swap\-halfwords\fR'
Swap the halfwords of each word (4 bytes) in the files.  This
option may be used in copy-in mode.
.TP
`\fB\-\-sparse\fR'
Write files with large blocks of zeros as sparse files.  This
option is used in copy-in and copy-pass modes.
.TP
`\fB\-t, \-\-list\fR'
Print a table of contents of the input.
.TP
`\fB\-\-to\-stdout\fR'
Extract files to standard output.  This option may be used in
copy-in mode.
.TP
`\fB\-u, \-\-unconditional\fR'
Replace all files, without asking whether to replace existing
newer files with older files.
.TP
`\fB\-v, \-\-verbose\fR'
List the files processed, or with `\fB\-t\fR', give an `\fBls \-l\fR' 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 \s-1UID\s0 and \s-1GID\s0 stored in the
archive.
.TP
`\fB\-V, \-\-dot\fR'
Print a `\fB.\fR' for each file processed.
.TP
`\fB\-W, \-\-warning\fR'
Control warning display. Currently FLAG is one of 'none', 'truncate', 'all'. Multiple options accumulate.
.TP
`\fB\-\-license\fR'
Print license and exit.
.TP
`\fB?, \-\-help\fR'
Give a help page similar to this manpage.
.TP
`\fB\-\-usage\fR'
Give a short usage message.
.TP
`\fB\-\-version\fR'
Print the cpio program version number and exit.

.PP
.SH EXAMPLES
When creating an archive, cpio takes the list of files to be
processed from the standard input, and then sends the archive to the
standard output, or to the device defined by the `\fB\-F\fR' option.
Usually find or ls is used to provide this list to
the standard input.  In the following example you can see the
possibilities for archiving the contents of a single directory.
.PP
.B % ls | cpio \-ov > directory.cpio
.PP
The `\fB\-o\fR' option creates the archive, and the `\fB\-v\fR' option prints the
names of the files archived as they are added.  Notice that the options
can be put together after a single `\fB\-\fR' or can be placed separately on
the command line.  The `\fB>\fR' redirects the cpio output to the file
`\fBdirectory.cpio\fR'.
.PP
If you wanted to archive an entire directory tree, the find command
can provide the file list to cpio:
.PP
.B % find . \-print \-depth | cpio \-ov > tree.cpio
.PP
This will take all the files in the current directory, the
directories below and place them in the archive tree.cpio.  Again the
`\fB\-o\fR' creates an archive, and the `\fB\-v\fR' option shows you the name of the
files as they are archived.  see \*(lqCopy\-out mode\*(rq.  Using the `\fB.\fR' in
the find statement will give you more flexibility when doing restores,
as it will save file names with a relative path vice a hard wired,
absolute path.  The `\fB\-depth\fR' option forces `\fBfind\fR' to print of the
entries in a directory before printing the directory itself.  This
limits the effects of restrictive directory permissions by printing the
directory entries in a directory before the directory name itself.
.PP
Extracting an archive requires a bit more thought because cpio will
not create directories by default.  Another characteristic, is it will
not overwrite existing files unless you tell it to.
.PP
.B % cpio \-iv < directory.cpio
.PP
This will retrieve the files archived in the file directory.cpio and
place them in the present directory.  The `\fB\-i\fR' option extracts the
archive and the `\fB\-v\fR' shows the file names as they are extracted.  If
you are dealing with an archived directory tree, you need to use the
`\fB\-d\fR' option to create directories as necessary, something like:
.PP
.B % cpio \-idv < tree.cpio
.PP
This will take the contents of the archive tree.cpio and extract it
to the current directory.  If you try to extract the files on top of
files of the same name that already exist (and have the same or later
modification time) cpio will not extract the file unless told to do so
by the \-u option.  see \*(lqCopy\-in mode\*(rq.
.PP
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.  see \*(lqCopy\-pass mode\*(rq.
.PP
.B % find . \-depth \-print0 | cpio \-\-null \-pvd new-dir
.PP
The example shows copying the files of the present directory, and
sub-directories to a new directory called new\-dir.  Some new options are
the `\fB\-print0\fR' available with \s-1GNU\s0 find, combined with the `\fB\-\-null\fR'
option of cpio.  These two options act together to send file names
between find and cpio, even if special characters are embedded in the
file names.  Another is `\fB\-p\fR', which tells cpio to pass the files it
finds to the directory `\fBnew-dir\fR'.

.SH BUGS
The GNU folks, in general, abhor man pages, and create info documents instead.  The maintainer of 
.B cpio 
falls
into  this  category.  Thus this man page may not be complete, nor current, and was included in the Red Hat
CVS tree because man is a great tool :).
.PP
.SH REPORTING BUGS
Please report bugs via https://bugzilla.redhat.com.
.PP
.SH SEE ALSO
The full documentation for
.B cpio
is maintained as a Texinfo manual.  If the
.B info
and
.B cpio
programs are properly installed at your site, the command
.IP
.B info cpio
.PP
should give you access to the complete manual. The online copy of the documentation 
is available at the following address:
.PP
http://www.gnu.org/software/cpio/manual