Category Archives: Basics

cpio ( GNU )

CoPy In Out

Usage: cpio [OPTION…] [destination-directory]
GNU `cpio’ copies files to and from archives

# Copy files named in name-list to the archive
cpio -o < name-list [> archive]
# Extract files from the archive
cpio -i [< archive]
# Copy files named in name-list to destination-directory
cpio -p destination-directory < name-list

Main operation mode:

-i, –extract
Extract files from an archive (run in copy-in
mode) -o, –create Create the archive (run in copy-out mode) -p, –pass-through Run in copy-pass mode

-t, –list Print a table of contents of the input

Operation modifiers valid in any mode:

–block-size=BLOCK-SIZE  Set the I/O block size to BLOCK-SIZE * 512
-B  Set the I/O block size to 5120 bytes
-c  Identical to “-H newc”, use the new (SVR4)
portable format.If you wish the old portable
(ASCII) archive format, use “-H odc” instead.
-C, –io-size=NUMBER  Set the I/O block size to the given NUMBER of
–force-local  Archive file is local, even if its name contains
-f, –nonmatching Only copy files that do not match any of the given patterns
-F, –file=[[[email protected]]HOST:]FILE-NAME
Use this FILE-NAME instead of standard input or output. Optional USER and HOST specify the user and host names in case of a remote archive
-H, –format=FORMAT  Use given archive FORMAT
-M, –message=STRING  Print STRING when the end of a volume of the
backup media is reached
-n, –numeric-uid-gid In the verbose table of contents listing, show
numeric UID and GID
–quiet  Do not print the number of blocks copied
–rsh-command=COMMAND  Use remote COMMAND instead of rsh
-v, –verbose  Verbosely list the files processed
-V, –dot  Print a “.” for each file processed
-W, –warning=FLAG  Control warning display. Currently FLAG is one of
‘none’, ‘truncate’, ‘all’. Multiple options

Operation modifiers valid only in copy-in mode:

-b, –swap  Swap both halfwords of words and bytes of
halfwords in the data. Equivalent to -sS
-r, –rename  Interactively rename files
-s, –swapbytes Swap the bytes of each halfword in the files
-S, –swap-halfwords  Swap the halfwords of each word (4 bytes) in the
–to-stdout  Extract files to standard output

-E, –pattern-file=FILE  Read additional patterns specifying filenames to
extract or list from FILE
–only-verify-crc  When reading a CRC format archive, only verify the
checksum of each file in the archive, don’t
actually extract the files

Operation modifiers valid only in copy-out mode:

-A, –append  Append to an existing archive.
-O [[[email protected]]HOST:]FILE-NAME Archive filename to use instead of standard  output. Optional USER and HOST specify the user and host names in case of a remote archive

Operation modifiers valid only in copy-pass mode:

-l, –link  Link files instead of copying them, when

Operation modifiers valid in copy-in and copy-out modes:

–absolute-filenames  Do not strip file system prefix components from
the file names
–no-absolute-filenames  Create all files relative to the current

Operation modifiers valid in copy-out and copy-pass modes:

-0, –null  A list of filenames is terminated by a null
character instead of a newline
-a, –reset-access-time  Reset the access times of files after reading
-I [[[email protected]]HOST:]FILE-NAME  Archive filename to use instead of standard input. Optional USER and HOST specify the user and host
names in case of a remote archive
-L, –dereference  Dereference symbolic links (copy the files
that they point to instead of copying the links).
-R, –owner=[USER][:.][GROUP]  Set the ownership of all files created to the specified USER and/or GROUP

Operation modifiers valid in copy-in and copy-pass modes:

-d, –make-directories  Create leading directories where needed
-m, –preserve-modification-time
Retain previous file modification times when creating files
–no-preserve-owner  Do not change the ownership of the files
–sparse  Write files with large blocks of zeros as sparse
-u, –unconditional  Replace all files unconditionally

-?, –help  give this help list
–usage  give a short usage message
–version  print program version

Mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options.

Report bugs to <[email protected]>.


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