CPIO(1) COMMAND REFERENCE CPIO(1)
NAME
cpio - copy file archives in and out
SYNOPSIS
cpio -i [ [ -B ] [ -F number ] [ -N size ] [ -P prompt ] [
-R path ] [ -S ] [ -V volume ] [ -b ] [ -c ] [ -d ] [ -f ] [
-m ] [ -n blocks ] [ -r ] [ -s ] [ -t ] [ -u ] [ -v ] [ -6 ]
] [ patterns ]
cpio -o [ -B ] [ -N size ] [ -P prompt ] [ -V volume ] [ -a
] [ -c ] [ -n blocks ] [ -v ] ]
cpio -p [ -a ] [ -d ] [ -l ] [ -m ] [ -r ] [ -u ] [ -v ] ]
directory
DESCRIPTION
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 given in the name-generating notation of
sh(1sh). In patterns, meta-characters ?, *, and [...] match
the slash / character. Multiple patterns may be specified
and if no patterns are specified, the default for patterns
is * (for example, select all files). The extracted files
are conditionally created and copied into the current
directory tree based upon the options described below.
This procedure is usually used to extract files from a cpio
archive file or tape.
Cpio -o (copy out) reads the standard input to obtain a list
of pathnames and copies those files onto the standard output
together with pathname and status information. The normal
procedure is to redirect the standard output to a file or
device (such as a tape drive), thus archiving the files.
Cpio -p (pass) reads the standard input to obtain a list of
pathnames of files that are conditionally created and copied
into the destination directory tree based upon the options
described below. This is similar to using cp(1) with the -r
option.
Multi-volume Archives
Cpio with the options -i and -o has the ability to handle
multi-volume files. The name of the device that data is to
be read from or written to can be specified by the -V
option. The number of 512-byte blocks on a volume can be
specified with the -n option (if this is not specified, cpio
goes until the system says the volume is full or empty).
When the volume is full or empty, the program enters an
interactive mode and prints the message
Printed 10/17/86 1
CPIO(1) COMMAND REFERENCE CPIO(1)
No more (data or space) on (Volume).
followed by a short explanation, which may either be the
default explanation or the text specified by the -P option.
If a device or filename was specified with the -V option, or
if a device or filename was specified in interactive mode
before, the same file or device can be used by typing
return. If no device or file has been named, the name of
the device or file to be used must be entered. (The
exception to this is when cpio was invoked to read or write
a regular file. In this case, typing return will cause cpio
to continue using the same file.) In case of disk or tape,
this should be the same device name that was used when the
command was invoked.
When using tapes or diskettes in this mode, you must have
the new tape or diskette ready to read or write before you
hit return.
This information is also supplied during interactive mode.
It is important to note that any type of file can be read or
written in this mode. This makes it possible to break up
archives into smaller pieces for easier transport.
Portability
Cpio archive headers contain the device numbers of the files
on the archives. The standard device number is 16 bits
wide, but it may be longer on some systems. This version of
cpio handles this difference in a portable way. On systems
with longer device numbers, device numbers for regular files
are hashed so that they will fit in the header and still be
unique for purposes of relinking. Device numbers for
special files are marked specially and stored in the data
area.
Because of this possible difference, cpio archives should
not be extracted (with -i ) by the superuser.
OPTIONS
-6 Process an old file (for example, UNIX System Sixth
Edition format). Only useful with -i (copy in).
-B Input/output is to be blocked 5,120 bytes to the record
(does not apply to the pass option; meaningful only with
data directed to or from tape or floppy disk.
-F number
Stop extracting or listing after number files have been
extracted/listed. This is only usable with the -i
option.
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CPIO(1) COMMAND REFERENCE CPIO(1)
-N size
Input/output is to be blocked size times 512 bytes to
the record (does not apply to the pass option;
meaningful only with data directed to or from tape of
floppy disk. The -B option is equivalent to -N 10.
(See CAVEATS.)
-P prompt
Print the given text instead of the default media change
text (see Multi-volume Archives above). The text is
printed as given, with no special processing done.
-R path
Copy relative to path. The given path is prepended to
all names beginning with a /. This action takes place
before the rename (-r option) process. This is only
usable with the -i option.
-S Swap half words. Use only with the -i option.
-V volume
Specifies the name of the file or device to read/write.
Can not be used with -p.
-a Reset access and modification times of input files after
they have been copied.
-b Swap both bytes and half words. Use only with the -i
option.
-c Write header information in ASCII character form for
portability.
-d Directories are to be created as needed.
-f Copy in all files except those in patterns.
-i Extracts files from the standard input which is assumed
to be the product of a previous cpio -o.
-l Whenever possible, link files rather than copying them.
Usable only with the -p option.
-m Retain previous file modification time. This option is
ineffective on directories that are being copied.
-n blocks
Specifies the number of 512-byte blocks that can be read
from or written to the volume (does not require the -V
option). When this number is reached, the program
enters interactive mode so that a new volume can be
mounted. Cannot be used with the -p option.
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CPIO(1) COMMAND REFERENCE CPIO(1)
-o Reads the standard input to obtain a list of pathnames
and copies those files onto the standard output together
with pathname and status information.
-p Reads the standard input to obtain a list of pathnames
of files that are conditionally created and copied into
the destination directory tree based upon the options.
-r Interactively renames files. If the user types a null
line, the file is skipped.
-s Swap bytes. Use only with the -i option.
-t Print a table of contents of the input. No files are
created.
-u Copy unconditionally (normally, an older file will not
replace a newer file with the same name).
-v Verbose: causes a list of filenames to be printed.
When used with the -t option, the table of contents
looks similar to the output of an ls -l command (see
ls(1)).
EXAMPLES
The first example below copies the contents of a directory
into an archive; the second duplicates a directory
hierarchy:
ls | cpio -o >/dev/mt0
cd olddir
find . -print | cpio -pdl newdir
This next example shows a typical use of cpio to archive a
directory and all subdirectories and place the archive in
the file ``arch.cpio''.
find dir -print | cpio -ov -V arch.cpio
The trivial case
find . -print | cpio -oB >/dev/rmt0
Printed 10/17/86 4
CPIO(1) COMMAND REFERENCE CPIO(1)
can be handled more efficiently by:
find . -cpio /dev/rmt0
RETURN VALUE
[NO_ERRS] Command completed without error.
[1] The user quit while changing volume.
[USAGE] Incorrect command line syntax. Execution
terminated.
[NP_WARN] An error warranting a warning message
occurred. Execution continues.
[NP_ERR] An error occurred that was not a system
error. Execution terminated.
[P_WARN] A system error occurred. Execution continues.
See intro(2) for more information on system
errors.
[P_ERR] A system error occurred. Execution
terminated. See intro(2) for more
information on system errors.
CAVEATS
The output from the -v option is placed on the standard
error. See the manual page for the shell being used for
information on redirecting the standard error.
On some versions of UNIX, pathnames in cpio archives are
restricted to 128 characters. This version restricts
pathnames to the system maximum (currently 1024); thus, the
resulting archives may be unportable.
If there are too many unique linked files, the program runs
out of memory to keep track of them and, thereafter, linking
information is lost.
Cpio does not know about symbolic links, but since it is
usually used with find, there is little danger of getting
into loops. Also, instead of archiving or copying symbolic
links, cpio copies the files pointed to by the links, if
they exist.
Only the superuser can copy special files.
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CPIO(1) COMMAND REFERENCE CPIO(1)
The editors ex, vi, e, edit, and view, and the programs more
and page will not allow the editing or displaying of non-
ASCII cpio archives. ASCII cpio archives are not restricted.
When using cpio with a streaming tape drive, the option -N
256 should be used in order to keep the tape streaming.
SEE ALSO
ar(1), cp(1), file(1), find(1), tar(1), cpio(5).
Printed 10/17/86 6
%%index%%
na:72,72;
sy:144,1115;
de:1259,2465;3868,2783;
op:6651,632;7427,2426;9997,1111;
ex:11108,602;11854,79;
rv:11933,850;
ca:12783,1047;13974,580;
se:14554,198;
%%index%%000000000189