CPIO(1) | General Commands Manual | CPIO(1)

# NAME

`cpio` — copy file archives in and out

# SYNOPSIS

`cpio` | `-o` [`-AaBcjLvZz`] [`-C` bytes] [`-F` archive] [`-H` format] [`-O` archive] < name-list [> archive]

`cpio` | `-i` [`-6BbcdfjmrSstuvZz`] [`-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 archive 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. Recognized formats are:

    bcpio
      Old binary `cpio` format.
    cpio
      Old octal character `cpio` format.
    pax
      POSIX pax format.
    sv4cpio
      SVR4 hex `cpio` format.
    tar
      Old tar format.
    ustar
      POSIX ustar format.
  `-j`
    Compress archive using the bzip2 format. The bzip2 utility must be installed separately.
  `-L`
    Follow symbolic links.
  `-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 standard 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 restore.
  `-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. Recognized formats are:

    bcpio
      Old binary `cpio` format.
    cpio
      Old octal character `cpio` format.
    pax
      POSIX pax format.
    sv4cpio
      SVR4 hex `cpio` format.
    tar
      Old tar format.
    ustar
      POSIX ustar format.
  `-j`
    Uncompress archive using the bzip2 format. The bzip2 utility must be installed separately.
  `-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 directories will be created.
  `-u`
    Overwrite files even when the file in the archive is older 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.

# EXIT STATUS

The `cpio` utility exits with one of the following values:

0
  All files were processed successfully.
1
  An error occurred.

# DIAGNOSTICS

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, `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 directories 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 ALSO

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 recommended that a format such as cpio or ustar be used for larger files.

File format | Maximum file size
bcpio | 4 Gigabytes
sv4cpio | 4 Gigabytes
cpio | 8 Gigabytes
pax | 8 Gigabytes
tar | 8 Gigabytes
ustar | 8 Gigabytes

# BUGS

The `-s` and `-S` options are currently not implemented.

December 9, 2023 | Debian