Mac Developer Library Developer
Search

 

This manual page is for Mac OS X version 10.9

If you are running a different version of Mac OS X, view the documentation locally:

  • In Terminal, using the man(1) command

Reading manual pages

Manual pages are intended as a quick reference for people who already understand a technology.

  • To learn how the manual is organized or to learn about command syntax, read the manual page for manpages(5).

  • For more information about this technology, look for other documentation in the Apple Developer Library.

  • For general information about writing shell scripts, read Shell Scripting Primer.




BSDCPIO(1)                BSD General Commands Manual               BSDCPIO(1)

NAME
     cpio -- copy files to and from archives

SYNOPSIS
     cpio {-i} [options] [pattern ...] [< archive]
     cpio {-o} [options] < name-list [> archive]
     cpio {-p} [options] dest-dir < name-list

DESCRIPTION
     cpio copies files between archives and directories.  This implementation can extract from tar, pax,
     cpio, zip, jar, ar, and ISO 9660 cdrom images and can create tar, pax, cpio, ar, and shar archives.

     The first option to cpio is a mode indicator from the following list:
     -i      Input.  Read an archive from standard input (unless overriden) and extract the contents to disk
             or (if the -t option is specified) list the contents to standard output.  If one or more file
             patterns are specified, only files matching one of the patterns will be extracted.
     -o      Output.  Read a list of filenames from standard input and produce a new archive on standard
             output (unless overriden) containing the specified items.
     -p      Pass-through.  Read a list of filenames from standard input and copy the files to the specified
             directory.

OPTIONS
     Unless specifically stated otherwise, options are applicable in all operating modes.

     -0      Read filenames separated by NUL characters instead of newlines.  This is necessary if any of
             the filenames being read might contain newlines.

     -A      (o mode only) Append to the specified archive.  (Not yet implemented.)

     -a      (o and p modes) Reset access times on files after they are read.

     -B      (o mode only) Block output to records of 5120 bytes.

     -C size
             (o mode only) Block output to records of size bytes.

     -c      (o mode only) Use the old POSIX portable character format.  Equivalent to --format odc.

     -d      (i and p modes) Create directories as necessary.

     -E file
             (i mode only) Read list of file name patterns from file to list and extract.

     -F file
             Read archive from or write archive to file.

     -f pattern
             (i mode only) Ignore files that match pattern.

     --format format
             (o mode only) Produce the output archive in the specified format.  Supported formats include:

             cpio     Synonym for odc.
             newc     The SVR4 portable cpio format.
             odc      The old POSIX.1 portable octet-oriented cpio format.
             pax      The POSIX.1 pax format, an extension of the ustar format.
             ustar    The POSIX.1 tar format.

             The default format is odc.  See libarchive_formats(5) for more complete information about the
             formats currently supported by the underlying libarchive(3) library.

     -H format
             Synonym for --format.

     -h, --help
             Print usage information.

     -I file
             Read archive from file.

     -i      Input mode.  See above for description.

     --insecure
             (i and p mode only) Disable security checks during extraction or copying.  This allows extrac-
             tion via symbolic links and path names containing `..' in the name.

     -J      (o mode only) Compress the file with xz-compatible compression before writing it.  In input
             mode, this option is ignored; xz compression is recognized automatically on input.

     -j      Synonym for -y.

     -L      (o and p modes) All symbolic links will be followed.  Normally, symbolic links are archived and
             copied as symbolic links.  With this option, the target of the link will be archived or copied
             instead.

     -l      (p mode only) Create links from the target directory to the original files, instead of copying.

     -lzma   (o mode only) Compress the file with lzma-compatible compression before writing it.  In input
             mode, this option is ignored; lzma compression is recognized automatically on input.

     -m      (i and p modes) Set file modification time on created files to match those in the source.

     -n      (i mode, only with -t) Display numeric uid and gid.  By default, cpio displays the user and
             group names when they are provided in the archive, or looks up the user and group names in the
             system password database.

     -no-preserve-owner
             (i mode only) Do not attempt to restore file ownership.  This is the default when run by non-root nonroot
             root users.

     -O file
             Write archive to file.

     -o      Output mode.  See above for description.

     -p      Pass-through mode.  See above for description.

     -preserve-owner
             (i mode only) Restore file ownership.  This is the default when run by the root user.

     --quiet
             Suppress unnecessary messages.

     -R [user][:][group]
             Set the owner and/or group on files in the output.  If group is specified with no user (for
             example, -R :wheel) then the group will be set but not the user.  If the user is specified with
             a trailing colon and no group (for example, -R root:) then the group will be set to the user's
             default group.  If the user is specified with no trailing colon, then the user will be set but
             not the group.  In -i and -p modes, this option can only be used by the super-user.  (For com-patibility, compatibility,
             patibility, a period can be used in place of the colon.)

     -r      (All modes.)  Rename files interactively.  For each file, a prompt is written to /dev/tty con-taining containing
             taining the name of the file and a line is read from /dev/tty.  If the line read is blank, the
             file is skipped.  If the line contains a single period, the file is processed normally.  Other-wise, Otherwise,
             wise, the line is taken to be the new name of the file.

     -t      (i mode only) List the contents of the archive to stdout; do not restore the contents to disk.

     -u      (i and p modes) Unconditionally overwrite existing files.  Ordinarily, an older file will not
             overwrite a newer file on disk.

     -v      Print the name of each file to stderr as it is processed.  With -t, provide a detailed listing
             of each file.

     --version
             Print the program version information and exit.

     -y      (o mode only) Compress the archive with bzip2-compatible compression before writing it.  In
             input mode, this option is ignored; bzip2 compression is recognized automatically on input.

     -Z      (o mode only) Compress the archive with compress-compatible compression before writing it.  In
             input mode, this option is ignored; compression is recognized automatically on input.

     -z      (o mode only) Compress the archive with gzip-compatible compression before writing it.  In
             input mode, this option is ignored; gzip compression is recognized automatically on input.

ENVIRONMENT
     The following environment variables affect the execution of cpio:

     LANG       The locale to use.  See environ(7) for more information.

     TZ         The timezone to use when displaying dates.  See environ(7) for more information.

EXIT STATUS
     The cpio utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
     The cpio command is traditionally used to copy file heirarchies in conjunction with the find(1) com-mand. command.
     mand.  The first example here simply copies all files from src to dest:
           find src | cpio -pmud dest

     By carefully selecting options to the find(1) command and combining it with other standard utilities,
     it is possible to exercise very fine control over which files are copied.  This next example copies
     files from src to dest that are more than 2 days old and whose names match a particular pattern:
           find src -mtime +2 | grep foo[bar] | cpio -pdmu dest

     This example copies files from src to dest that are more than 2 days old and which contain the word
     ``foobar'':
           find src -mtime +2 | xargs grep -l foobar | cpio -pdmu dest

COMPATIBILITY
     The mode options i, o, and p and the options a, B, c, d, f, l, m, r, t, u, and v comply with SUSv2.

     The old POSIX.1 standard specified that only -i, -o, and -p were interpreted as command-line options.
     Each took a single argument of a list of modifier characters.  For example, the standard syntax allows
     -imu but does not support -miu or -i -m -u, since m and u are only modifiers to -i, they are not com-mand-line command-line
     mand-line options in their own right.  The syntax supported by this implementation is backwards-compat-ible backwards-compatible
     ible with the standard.  For best compatibility, scripts should limit themselves to the standard syn-tax. syntax.
     tax.

SEE ALSO
     bzip2(1), tar(1), gzip(1), mt(1), pax(1), libarchive(3), cpio(5), libarchive-formats(5), tar(5)

STANDARDS
     There is no current POSIX standard for the cpio command; it appeared in ISO/IEC 9945-1:1996
     (``POSIX.1'') but was dropped from IEEE Std 1003.1-2001 (``POSIX.1'').

     The cpio, ustar, and pax interchange file formats are defined by IEEE Std 1003.1-2001 (``POSIX.1'') for
     the pax command.

HISTORY
     The original cpio and find utilities were written by Dick Haight while working in AT&T's Unix Support
     Group.  They first appeared in 1977 in PWB/UNIX 1.0, the ``Programmer's Work Bench'' system developed
     for use within AT&T.  They were first released outside of AT&T as part of System III Unix in 1981.  As
     a result, cpio actually predates tar, even though it was not well-known outside of AT&T until some time
     later.

     This is a complete re-implementation based on the libarchive(3) library.

BUGS
     The cpio archive format has several basic limitations: It does not store user and group names, only
     numbers.  As a result, it cannot be reliably used to transfer files between systems with dissimilar
     user and group numbering.  Older cpio formats limit the user and group numbers to 16 or 18 bits, which
     is insufficient for modern systems.  The cpio archive formats cannot support files over 4 gigabytes,
     except for the ``odc'' variant, which can support files up to 8 gigabytes.

BSD                            December 21, 2007                           BSD

Reporting Problems

The way to report a problem with this manual page depends on the type of problem:

Content errors
Report errors in the content of this documentation with the feedback links below.
Bug reports
Report bugs in the functionality of the described tool or API through Bug Reporter.
Formatting problems
Report formatting mistakes in the online version of these pages with the feedback links below.

Feedback