CPIO(1) BSD Reference Manual CPIO(1)NAMEcpio - copy file archives in and out
SYNOPSIScpio-o [-AaBcLvZz] [-C bytes] [-F archive] [-H format] [-M flag] [-O
archive] < name-list [> archive]
cpio-i [-6BbcdfmrSstuvZz] [-C bytes] [-E file] [-F archive] [-H format]
[-I archive] [pattern ...] [< archive]
cpio-p [-adLlmuv] destination-directory < name-list
DESCRIPTION
The cpio command copies files to and from a cpio archive.
The options are as follows:
-o Create an archive. Reads the list of files to store in the ar-
chive from standard input, and writes the archive on standard
output.
-A Append to the specified archive.
-a Reset the access times on files that have been copied to
the archive.
-B Set block size of output to 5120 bytes.
-C bytes
Set the block size of output to bytes.
-c Use ASCII format for cpio header for portability.
-F archive
Use the specified file as the input for the archive.
-H format
Write the archive in the specified format. Recognised
formats are:
ar Unix Archiver.
bcpio Old binary cpio format. Selected by -6.
cpio Old octal character cpio format. Selected by -c.
sv4cpio SVR4 hex cpio format.
sv4crc SVR4 hex cpio format with checksums. This is the
default format for creating new archives.
tar Old tar format.
ustar POSIX ustar format.
bin These
crc four
newc formats
odc are supported for backwards compatibility only.
-L Follow symbolic links.
-M flag
Configure the archive normaliser. flag is either a numer-
ic value compatible to strtonum(3) which is directly
stored in the flags word, or one of the following values,
optionally prefixed with "no-" to turn them off:
inodes 0x0001: Serialise inodes, zero device info.
(cpio, sv4cpio, sv4crc)
links 0x0002: Store content of hard links only once.
(cpio, sv4cpio, sv4crc)
mtime 0x0004: Zero out the file modification time.
(ar, cpio, sv4cpio, sv4crc, ustar)
uidgid 0x0008: Set owner to 0:0 (root:wheel).
(ar, cpio, sv4cpio, sv4crc, ustar)
verb 0x0010: Debug this option.
debug 0x0020: Debug file header storage.
lncp 0x0040: Extract hard links by copy if link fails.
numid 0x0080: Use only numeric uid and gid values.
(ustar)
gslash 0x0100: Append a slash after directory names.
(ustar)
set 0x0003: Keep ownership and mtime intact.
dist 0x008B: Clean everything except mtime.
norm 0x008F: Clean everything.
root 0x0089: Clean owner and device information.
This option is only implemented for the ar, cpio,
sv4cpio, sv4crc, and ustar file format writing routines.
-O archive
Use the specified file name as the archive to write to.
-v Be verbose about operations. List filenames as they are
written to the archive.
-Z Compress archive using compress(1) format.
-z Compress archive using gzip(1) format.
-i Restore files from an archive. Reads the archive file from stan-
dard input and extracts files matching the patterns that were
specified on the command line.
-6 Process old-style cpio format archives.
-B Set the block size of the archive being read to 5120
bytes.
-b Do byte and word swapping after reading in data from the
archive, for restoring archives created on systems with a
different byte order.
-C bytes
Read archive written with a block size of bytes.
-c Expect the archive headers to be in ASCII format.
-d Create any intermediate directories as needed during re-
store.
-E file
Read list of file name patterns to extract or list from
file.
-F archive, -I archive
Use the specified file as the input for the archive.
-f Restore all files except those matching the patterns
given on the command line.
-H format
Read an archive of the specified format. Recognised for-
mats are:
ar Unix Archiver.
bcpio Old binary cpio format.
cpio Old octal character cpio format.
sv4cpio SVR4 hex cpio format.
sv4crc SVR4 hex cpio format with checksums.
tar Old tar format.
ustar POSIX ustar format.
bin These
crc four
newc formats
odc are supported for backwards compatibility only.
-m Restore modification times on files.
-r Rename restored files interactively.
-S Swap words after reading data from the archive.
-s Swap bytes after reading data from the archive.
-t Only list the contents of the archive, no files or direc-
tories will be created.
-u Overwrite files even when the file in the archive is old-
er than the one that will be overwritten.
-v Be verbose about operations. List filenames as they are
copied in from the archive.
-Z Uncompress archive using compress(1) format.
-z Uncompress archive using gzip(1) format.
-p Copy files from one location to another in a single pass. The
list of files to copy are read from standard input and written
out to a directory relative to the specified directory argument.
-a Reset the access times on files that have been copied.
-d Create any intermediate directories as needed to write
the files at the new location.
-L Follow symbolic links.
-l When possible, link files rather than creating an extra
copy.
-m Restore modification times on files.
-u Overwrite files even when the original file being copied
is older than the one that will be overwritten.
-v Be verbose about operations. List filenames as they are
copied.
ENVIRONMENT
TMPDIR Path in which to store temporary files.
ERRORScpio will exit with one of the following values:
0 All files were processed successfully.
1 An error occurred.
Whenever cpio cannot create a file or a link when extracting an archive
or cannot find a file while writing an archive, or cannot preserve the
user ID, group ID, file mode, or access and modification times when the
-p option is specified, a diagnostic message is written to standard error
and a non-zero exit value will be returned, but processing will continue.
In the case where cpio cannot create a link to a file, unless -M lncp is
given, cpio will not create a second copy of the file.
If the extraction of a file from an archive is prematurely terminated by
a signal or error, cpio may have only partially extracted the file the
user wanted. Additionally, the file modes of extracted files and direc-
tories may have incorrect file bits, and the modification and access
times may be wrong.
If the creation of an archive is prematurely terminated by a signal or
error, cpio may have only partially created the archive, which may
violate the specific archive format specification.
SEE ALSOar(1), pax(1), tar(1)AUTHORS
Keith Muller at the University of California, San Diego.
CAVEATS
Different file formats have different maximum file sizes. It is recom-
mended that a format such as cpio or ustar be used for larger files.
File format Maximum file size
ar 10 Gigabytes - 1 Byte
bcpio 4 Gibibytes
sv4cpio 4 Gibibytes
cpio 8 Gibibytes
tar 8 Gibibytes
ustar 8 Gibibytes
The backwards-compatible format options are not available in the pax(1)
front-end.
The -M option is a MirBSD extensions, available starting with MirOS #8.
Archives written using these options are, however, compatible to the
standard and should be readable on any other system. The only option
whose behaviour is not explicitly allowed by the standard is hard link
unification (write file contens only once) selected by -M 0x0002.
The ar file format matches APT repositories and the BSD ar(1) specifica-
tion, not GNU binutils or SYSV systems.
BUGS
The -s and -S options are currently not implemented.
MirOS August 17, 2011 3
