NAME
cpio - copy file archives in and out
SYNOPSIS
cpio -i [ bBcdfkmrsStuvV6 ] [ -C bufsize ] [ -E filename ]
[ -H header ] [ -I filename [ -M message ] ] [ -R id ]
[ pattern ... ]
cpio -o [ aABcLvV ] [ -C bufsize ] [ -H header ]
[ -O filename [ -M message ] ]
cpio -p [ adlLmuvV ] [ -R id ] directory
AVAILABILITY
SUNWcsu
DESCRIPTION
cpio copies files in to and out from a cpio archive. The
cpio achive may span multiple volumes. The -i, -o, and -p
options select the action to be performed. The following
list describes each of the actions (which are mutually
exclusive).
cpio -i (copy in) extracts files from the standard input,
which is assumed to be the product of a previous cpio -o.
Only files with names that match patterns are selected.
patterns are regular expressions given in the filename-
generating notation of sh(1). In patterns, meta-characters
?, * , and [...] match the slash (/) character, and
backslash (\) is an escape character. A ! meta-character
means not. (For example, the !abc* pattern would exclude
all files that begin with abc.) Multiple patterns may be
specified and if no patterns are specified, the default for
patterns is * (that is, select all files). Each pattern
must be enclosed in double quotes; otherwise, the name of a
file in the current directory might be used. Extracted
files are conditionally created and copied into the current
directory tree based on the options described below. The
permissions of the files will be those of the previous cpio
-o. Owner and group will be the same as the current user
unless the current user is super-user. If this is true,
owner and group will be the same as those resulting from the
previous cpio -o. Note: If cpio -i tries to create a file
that already exists and the existing file is the same age or
younger (newer), cpio will output a warning message and not
replace the file. (The -u option can be used to overwrite,
unconditionally, the existing file.)
cpio -o (copy out) reads the standard input to obtain a list
of path names and copies those files onto the standard out-
put together with path name and status information. Output
is padded to a 512-byte boundary by default or to the user
specified block size (with the -B or -C options) or to some
device-dependent block size where necessary (as with the CTC
tape).
cpio -p (pass) reads the standard input to obtain a list of
path names of files that are conditionally created and
copied into the destination directory tree based on the
options described below.
Note: cpio assumes four-byte words.
If, when writing to a character device (-o) or reading from
a character device (-i), cpio reaches the end of a medium
(such as the end of a diskette), and the -O and - I options
are not used, cpio prints the following message:
To continue, type device/file name when ready.
To continue, you must replace the medium and type the char-
acter special device name (/dev/rdiskette for example) and
press RETURN. You may want to continue by directing cpio to
use a different device. For example, if you have two floppy
drives you may want to switch between them so cpio can
proceed while you are changing the floppies. (Simply press-
ing RETURN causes the cpio process to exit.)
OPTIONS
-i cpio -i (copy in) extracts files from the
standard input.
-o cpio -o (copy out) reads the standard input
to obtain a list of path names and copies
those files onto the standard output.
-p cpio -p (pass) reads the standard input to
obtain a list of path names of files.
-a Reset access times of input files after they
have been copied. Access times are not reset
for linked files when cpio -pla is specified
(mutually exclusive with -m).
-A Append files to an archive. The - A option
requires the - O option. Valid only with
archives that are files, or that are on
floppy diskettes or hard disk partitions.
-b Reverse the order of the bytes within each
word. (Use only with the -i option.)
-B Block input/output 5120 bytes to the record.
The default buffer size is 512 bytes when
this and the -C options are not used. ( - B
does not apply to the pass option; -B is
meaningful only with data directed to or from
a character special device, for example,
/dev/rmt/0m .)
-c Read or write header information in ASCII
character form for portability. Always use
this option (or the -H option) when the ori-
gin and the destination machines are dif-
ferent types (mutually exclusive with -H and
- 6). The -c option implies expanded device
numbers. When transferring files between
Solaris 1.x and Solaris 2.x use regular cpio
format. Don't use the -c or -H options.
-C bufsize Block input/output bufsize bytes to the
record, where bufsize is replaced by a posi-
tive integer. The default buffer size is 512
bytes when this and -B options are not used.
(-C does not apply to the pass option; -C is
meaningful only with data directed to or from
a character special device, for example,
/dev/rmt/0m.)
-d Create directories as needed.
-E filename Specify an input file (file) that contains a
list of filenames to be extracted from the
archive (one filename per line).
-f Copy in all files except those in patterns.
(See the paragraph on cpio -i for a descrip-
tion of patterns.)
-H header Read or write header information in header
format. Always use this option or the -c
option when the origin and the destination
machines are different types (mutually
exclusive with -c and -6). When transferring
files between Solaris 1.x and Solaris 2.x use
regular cpio format. Don't use the -c or - H
options.
Valid values for header are:
bar bar head and format. Used only
with the - i option ( read
only)
crc|CRC ASCII header with expanded
device numbers and an addi-
tional per-file checksum
odc ASCII header with small device
numbers
tar|TAR tar header and format
ustar|USTAR IEEE/P1003 Data Interchange
Standard header and format
-I filename Read the contents of filename as an input
archive. If filename is a character special
device, and the current medium has been com-
pletely read, replace the medium and press
RETURN to continue to the next medium. This
option is used only with the -i option.
-k Attempt to skip corrupted file headers and
I/O errors that may be encountered. If you
want to copy files from a medium that is cor-
rupted or out of sequence, this option lets
you read only those files with good headers.
(For cpio archives that contain other cpio
archives, if an error is encountered cpio may
terminate prematurely. cpio will find the
next good header, which may be one for a
smaller archive, and terminate when the
smaller archive's trailer is encountered.)
Used only with the -i option.
-l Whenever possible, link files rather than
copying them. (Usable only with the -p
option.)
-L Follow symbolic links. The default is not to
follow symbolic links.
- m Retain previous file modification time.
This option is ineffective on directories
that are being copied (mutually exclusive
with -a).
-M message Define a message to use when switching
media. When you use the -O or -I options and
specify a character special device, you can
use this option to define the message that is
printed when you reach the end of the medium.
One %d can be placed in message to print the
sequence number of the next medium needed to
continue.
-O filename Direct the output of cpio to filename. If
filename is a character special device and
the current medium is full, replace the
medium and type a carriage return to continue
to the next medium. Use only with the - o
option.
-r Interactively rename files. If the user
types a carriage return alone, the file is
skipped. If the user types a ``.'' the ori-
ginal pathname will be retained. (Not avail-
able with cpio -p.)
-R id Reassign ownership and group information for
each file to user ID (ID must be a valid
login ID from /etc/passwd). This option is
valid only for the super-user.
-s Swap bytes within each half word.
-S Swap halfwords within each word.
-t Print a table of contents of the input. No
files are created (mutually exclusive with -
V).
-u Copy unconditionally (normally, an older
file will not replace a newer file with the
same name).
-v Verbose. Print a list of file names. When
used with the -t option, the table of con-
tents looks like the output of an ls -l com-
mand ( see ls(1) ).
-V Special verbose. Print a dot for each file
read or written. Useful to assure the user
that cpio is working without printing out all
file names.
-6 Process a UNIX System Sixth Edition archive
format file. Use only with the -i option
(mutually exclusive with -c and -H)).
EXAMPLES
The following examples show three uses of cpio.
When standard input is directed through a pipe to cpio - o,
it groups the files so they can be directed (>) to a single
file (../newfile). The -c option insures that the file will
be portable to other machines (as would the -H option).
Instead of ls(1), you could use find(1), echo(1), cat(1),
and so on, to pipe a list of names to cpio. You could
direct the output to a device instead of a file.
example% ls | cpio -oc >> ../newfile
cpio -i uses the output file of cpio -o (directed through a
pipe with cat in the example below), extracts those files
that match the patterns (memo/a1, memo/b*), creates direc-
tories below the current directory as needed (-d option),
and places the files in the appropriate directories. The -c
option is used if the input file was created with a portable
header. If no patterns were given, all files from newfile
would be placed in the directory.
example% cat newfile | cpio -icd "memo/a1" "memo/b*"
cpio -p takes the file names piped to it and copies or links
( -l option) those files to another directory (newdir in the
example below). The -d option says to create directories as
needed. The - m option says retain the modification time.
(It is important to use the -depth option of find(1) to gen-
erate path names for cpio. This eliminates problems cpio
could have trying to create files under read-only direc-
tories.) The destination directory, newdir, must exist.
example% find . -depth -print | cpio -pdlmv newdir
Note: When you use cpio in conjunction with find, if you
use the - L option with cpio then you must use the -follow
option with find and vice versa. Otherwise there will be
undesirable results.
Note that for multi-reel archives, dismount the old volume,
mount the new one, and continue to the next tape by typing
the name of the next device (probably the same as the first
reel). To stop, type a RETURN and cpio will end.
ENVIRONMENT
If any of the LC_* variables ( LC_CTYPE, LC_MESSAGES,
LC_TIME, LC_COLLATE, LC_NUMERIC, and LC_MONETARY ) (see
environ(5)) are not set in the environment, the operational
behavior of cpio for each corresponding locale category is
determined by the value of the LANG environment variable.
If LC_ALL is set, its contents are used to override both the
LANG and the other LC_* variables. If none of the above
variables is set in the environment, the "C" (U.S. style)
locale determines how cpio behaves.
LC_CTYPE
Determines how cpio handles characters. When LC_CTYPE
is set to a valid value, cpio can display and handle
text and filenames containing valid characters for that
locale. cpio can display and handle Extended Unix Code
(EUC) characters where any individual character can be
1, 2, or 3 bytes wide. cpio can also handle EUC charac-
ters of 1, 2, or more column widths. In the "C" locale,
only characters from ISO 8859-1 are valid.
LC_MESSAGES
Determines how diagnostic and informative messages are
presented. This includes the language and style of the
messages, and the correct form of affirmative and nega-
tive responses. In the "C" locale, the messages are
presented in the default form found in the program
itself (in most cases, U.S. English).
LC_TIME
Determines how cpio handles date and time formats. In
the "C" locale, date and time handling follows the U.S.
rules.
SEE ALSO
ar(1), cat(1), echo(1), find(1), ls(1), sh(1), tar(1),
archives(4), environ(5)
NOTES
Path names are restricted to 256 characters for the binary
(the default) and
-H odc header formats. Otherwise, path names are restricted
to 1024 characters.
Only the super-user can copy special files.
Blocks are reported in 512-byte quantities.
If a file has 000 permissions, contains more than 0 charac-
ters of data, and the user is not root, the file will not be
saved or restored.
The inode number stored in the header,
(/usr/include/archives.h) is an unsigned short which is 2
bytes. This limits the range of inode numbers from 0 to
65535. Files which are hard linked must fall in this inode
range. This could be a problem when moving cpio archives
between different vendors' machines.