CPIO(1)CPIO(1)NAME
cpio - copy file archives in and out
SYNOPSIS
cpio −i [ BcdmrtuvfsSb6 ] [ patterns ]
cpio −o [ acBv ]
cpio −p [ adlmruv ] directory
DESCRIPTION
The cpio utility has three functional modes: copy in, copy out and
pass.
Functional Options:
−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(1). 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 ``*''
(i.e., select all files). The extracted files are
conditionally created and copied into the current directory
tree based upon the options described below. The permissions
of the files will be those of the previous cpio −o. The
owner and group of the files will be that of the current user
unless the user is super-user, which causes cpio to retain
the owner and group of the files of the previous cpio −o.
−o Copy out. Reads the standard input to obtain a list of path
names and copies those files onto the standard output
together with path name and status information. Output is
padded to a 512-byte boundary.
−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 upon the options
described below.
Options for the above functional options:
−B Input/output is to be blocked 5,120 bytes to the record (does
not apply to the pass options; meaningful only with data
directed to or from /dev/rmt/??).
−S Swap halfwords. Use only with the −i option.
−a Reset access times of input files after they have been
copied.
−b halfwords. 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.
−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.
−r Interactively rename 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 file names to be printed. When
used with the t option, the table of contents looks like the
output of an ``ls -l'' command (see ls(1))
−6 Process an old (i.e., UNIX System Sixth Edition format) file.
Only useful with −i (copy in).
EXAMPLES
The first example below copies the contents of a directory into an
archive; the second duplicates a directory hierarchy:
ls | cpio -o > edev/rmt/0m
cd olddir
find . -depth -print | cpio -pdl newdir
The trivial case
find . -depth -print | cpio -oB >/dev/fmt/0m
can be handled more efficiently by:
find . -cpio /dev/rmt/0m
SEE ALSOar(1), find(1), ls(1), cpio(4)HISTORY
The cpio command appeared in System V AT&T UNIX. This program is
derived from the System V AT&T sources contributed to the public domain
by AT&T.
BUGS
Path names are restricted to 128 characters. 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. Only the super-user
can copy special files. The −B option does not work with certain
magnetic tape drives.
March 14, 1991 CPIO(1)