cpio(1)cpio(1)NAMEcpio - Copies files to and from archive storage.
SYNOPSIScpio -o[aBcehvV] [-C value] [-M"string"] [-Odevice]
cpio -i[bBcdefmrsStuvz6] [-C value] [-M"string"] [-Idevice] [pat‐
tern...]
cpio -p[adlmruvV] directory
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
cpio: XCU5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
OPTIONS
A hyphen (-) is required before the -i, -I, -o, -O, and -p options; all
other options follow -i, -o, or -p without leading spaces and without a
hyphen.
[Tru64 UNIX] The following two options are preceded by a hyphen and
must be used separately from the other options. [Tru64 UNIX] Speci‐
fies the input device containing the archive. This argument must be
present to import data from a device. [Tru64 UNIX] Specifies the out‐
put device to store the archive. This argument must be present to
export data to a device.
Not all of the following options can be used with each of the -o, -i,
and -p options. Resets the access times of copied files to the current
time. (When the l option is also specified, the access times of the
linked files are not reset.) [Tru64 UNIX] Swaps both bytes and half‐
words. (See also the s and S options.) If there is an odd number of
bytes or halfwords in the file being processed, data can be lost. This
option can only be used with cpio-i. Performs block input/output,
5120 bytes to a record. This option cannot be used with cpio-p. It is
meaningful only with data directed to or from /dev/tape/tape*. This
option does not work with certain magnetic tape drives. The C and B
options are mutually exclusive. If you specify both, the last one on
the command line is used. Writes header information in ASCII character
form. Specify this option when POSIX compliance is required and when
you are creating or restoring archives for or from another system.
[Tru64 UNIX] Performs block input/output using value as the record
size. The C and B options are mutually exclusive. If you specify
both, the last one on the command line is used. Creates directories as
needed. [Tru64 UNIX] Read or write cpio header information in
extended cpio header format. Use this option to read or write block
special or character special files. Any cpio archives created with the
e option of Tru64 UNIX Version 4.0 are not backward compatible with
earlier versions of Tru64 UNIX. Copies all files except those matching
pattern (cpio -i only). [Tru64 UNIX] Forces cpio to follow symbolic
links as if they were normal files or directories. The cpio command
does not follow symbolic links, but instead saves the link text in the
archive. Links files rather than copying them, whenever possible. Hard
links are created rather than symbolic (soft) links. This option can be
used only with cpio-p. Retains the previous file modification time.
This option cannot be used when copying directories. [Tru64
UNIX] Specifies the End-of-Media message. This option is used to cus‐
tomize the message that appears when it is time to change archive vol‐
umes. The -M option is valid only when -I or -O is also specified.
Causes cpio to ask whether or not to rename each file before copying
it. If you do not want to change the file name, enter the current file
name. You can press <Return> only to have cpio skip copying the file.
[Tru64 UNIX] Swaps bytes. This option can be used only with cpio-i.
If there is an odd number of bytes in the file being processed, data
can be lost. [Tru64 UNIX] Swaps halfwords. This option can be used
only with cpio-i. If there is an odd number of halfwords in the file
being processed, data can be lost. Creates a table of contents of the
input. This option does not copy any files. Copies unconditionally.
Otherwise, a file from the archive with the same name as an existing
file in the file system is copied only if the archived file is the
newer one. Lists file names. If you use this option with the t
option, the output looks similar to that of the ls -l command. [Tru64
UNIX] Prevents any extended attributes from being archived with asso‐
ciated files. This option is particularly useful for archiving files
that are to be restored with previous versions of tar and cpio. [Tru64
UNIX] Positions the tape after the EOF marker on extraction or list‐
ing. The z option lets the user extract or list tapes that have multi‐
ple archives on them one after the other without error as a result of
the tape not being positioned correctly for the next extraction or
listing. [Tru64 UNIX] Processes an old file (one written in UNIX
Sixth Edition format). This option can be used only with cpio-i.
OPERANDS
A pathname of an existing directory to be used as the target of cpio-p. Expressions making use of a pattern-matching notation similar to
that used by the shell for file name pattern matching, and similar to
regular expressions. The following metacharacters are defined: Matches
any string, including the empty string. Matches any single character.
Matches any one of the enclosed characters. A pair of characters sepa‐
rated by `-' matches any symbol between the pair (inclusive), as
defined by the system default collating sequence.
In pattern, the special characters ?, *, and [ also match the /
character.
Multiple cases of pattern can be specified and if no pattern is
specified, the default for pattern is * (that is, select all
files).
DESCRIPTION
The cpio command copies files between archive storage and the file sys‐
tem. It is used to save and restore data from traditional format cpio
archives.
There are three versions of the cpio command:
cpio-o (copy out)
This command reads file pathnames from standard input and copies these
files to standard output along with pathnames and status information.
Output is padded to a 512-byte boundary.
cpio-i (copy in)
This command reads from standard input an archive file created by the
cpio-o command and copies from it the files with names that match pat‐
tern. These files are copied into the current directory tree. The
file permissions are the same as the permissions associated with the
files copied out using cpio-o but if umask is used it sets the permis‐
sions as per umask. The owner and group of the files are those of the
current user unless the user is superuser, in which case cpio retains
the owner and group of the files of the previous cpio-o.
You can list more than one pattern using the file name notation
described. The default pattern is *, selecting all files in the ar‐
chive. In an expression such as [a-z], the hyphen means “through”
according to the current collating sequence. The collating sequence is
determined by the LC_COLLATE environment variable.
cpio-p (directory copy)
This command reads file pathnames from standard input and copies these
files into the named directory. The specified directory must already
exist. If these pathnames include directory names and if these direc‐
tories do not already exist, you must use the -d option to cause the
directories to be created.
[Tru64 UNIX] Special files are not supported. Pathnames cannot exceed
128 bytes. Avoid giving cpio pathnames made up of many uniquely linked
files because cpio might not have enough memory to keep track of them
and could lose linking information.
NOTES
The cpio command is marked as LEGACY in XCU Issue 5.
[Tru64 UNIX] Archives created with extended attributes cannot be read
by Version 2.0 of the cpio command. The following describes the
results of restoring archived files and directories when you use Ver‐
sion 2.0 of the cpio command: [Tru64 UNIX] You cannot restore an ar‐
chive directory with extended attributes. The extended attributes are
restored as a regular file that cannot be overwritten; the original
directory cannot be recreated. In addition, the cpio command restores
the archived files containing extended attributes as regular files.
When the cpio command restores the original file with the extended
attributes, the command fails with errno:20. [Tru64 UNIX] You cannot
archive files with extended attributes. [Tru64 UNIX] Archives created
with the new pax utility and having cpio format, can be restored using
only the new pax or cpio commands even if none of the archived files
have extended attributes.
To achieve backward compatibility of archived files, use the following
suggestions: Archive only files that do not have extended attributes.
Use the old cpio command at /usr/opt/obsolete/usr/bin/cpio.
Socket files are ignored while archiving through the cpio command.
CAUTIONS
[Tru64 UNIX] When redirecting the output from cpio to a special file
(device), redirect it to the raw device and not the block device.
Because writing to a block device is done asynchronously, there is no
way to know if the end of the device has been reached.
EXIT STATUS
The following exit values are returned: Successful completion. An
error occurred.
EXAMPLES
To copy files to magnetic tape, enter: cpio-ov < file-list
-O/dev/tape/tape0
This command copies the files with pathnames that are listed in
the file specification in a compact form to the magnetic tape
(/dev/tape/tape0). The -v option causes cpio to display the
name of each file as it is copied. This command is useful for
making backup copies of files. To copy files in the current
directory whose names end with onto magnetic tape, enter: ls *.c
| cpio-ov -O/dev/tape/tape0
To copy the current directory and all subdirectories onto mag‐
netic tape, enter: find . -print | cpio-ov -O/dev/tape/tape0
This command saves the directory tree that starts with the cur‐
rent directory (.) and includes all of its subdirectories and
files. Another way to do the same thing is by entering the fol‐
lowing command: find . -cpio /dev/tape/tape0 -print
The -print option displays the name of each file as it is
copied. To list the files that have been saved onto a magnetic
tape with cpio, enter: cpio-itv -I/dev/tape/tape0
This command displays the table of contents of the data previ‐
ously saved onto /dev/tape/tape0 in cpio format. To list only
the file pathnames, use only the -it options. To copy the files
previously saved with cpio from a magnetic tape, enter: cpio-idmv -I/dev/tape/tape0
This command copies the files previously saved onto
/dev/tape/tape0 by cpio back into the file system (specified by
the -i option). The -d option lets cpio create the appropriate
directories if a directory tree was saved. The -m option main‐
tains the last modification time that was in effect when the
files were saved. The -v option causes cpio to display the name
of each file as it is copied. To copy selected files from mag‐
netic tape, enter: cpio-i -I/dev/tape/tape0 "*.c" "*.o"
This command copies the files that end with or from magnetic
tape. The patterns *.c and *.o must be enclosed in double quo‐
tation marks (" ") to prevent the shell from treating the *
(asterisk) as a pattern-matching character. In this special
case, cpio itself decodes the pattern-matching characters. To
rename files as they are copied from magnetic tape, enter: cpio-ir -I/dev/tape/tape0
The -r option causes cpio to ask you whether or not to rename
each file before copying it from magnetic tape. For example,
the following message asks you whether you want to give the file
saved as prog.c a new name as it is being copied: Rename
<prog.c>
To rename the file, type the new name and press <Return>. To
keep the same name, you must enter the old name at the prompt.
To avoid copying the file at all, press <Return> alone. To copy
a directory and all of its subdirectories, enter: mkdir
/u/jim/newdir find . -print | cpio-pdl /u/jim/newdir
This command duplicates the current directory tree, including
the current directory and all of its subdirectories and files.
The duplicate is placed in the new /u/jim/newdir directory. The
-l option causes cpio to link files instead of copying them,
when possible.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of cpio: Pro‐
vides a default value for the internationalization variables that are
unset or null. If LANG is unset or null, the corresponding value from
the default locale is used. If any of the internationalization vari‐
ables contain an invalid setting, the utility behaves as if none of the
variables had been defined. If set to a non-empty string value, over‐
rides the values of all the other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to multi‐
byte characters in arguments and input files) and the behavior of char‐
acter classes within bracketed file name patterns. Determines the
locale for the format and contents of diagnostic messages written to
standard error. Determines the format of date and time strings output
when listing the contents of an archive with the -v option. Determines
the location of message catalogues for the processing of LC_MESSAGES.
Determines the time zone used with date and time strings.
SEE ALSO
Commands: ar(1), find(1), ls(1), ksh(1), pax(1), Bourne shell sh(1b),
POSIX shell sh(1p), tar(1)
Files: tar(4)
Standards: standards(5)cpio(1)