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| Chapter 2 UNIX Commands |

## tar

    tar [options] [files]

Copy `files` to or restore `files` from tape. If any `files` are directories, tar acts on the entire subtree. Options need not be preceded by -. Note that options are supplied as one group, with any arguments placed afterward in corresponding order.

### Function options (choose one)

c

  Create a new tape.

r

  Append `files` to tape.

t

  Print the names of `files` if they are stored on the tape (if `files` not specified, print names of all files).

u

  Add files if not on tape or if modified.

x

  Extract `files` from tape (if `files` not specified, extract all files).

### Options

b `n`

  Use blocking factor `n` (default is 1; maximum is 20).

f `arch`

  Store files in or extract files from archive `arch`; `arch` is usually a device name (default is /dev/mt0). If `arch` is -, standard input or output is used as appropriate (e.g., when piping a tar archive to a remote host).

l

  Print error messages about links it can't find.

L

  Follow symbolic links.

m

  Do not restore file modification times; update them to the time of extraction.

o

  Change ownership of extracted files to that of user running program.

v

  Print function letter (`x` for extraction or `a` for archive) and name of files.

w

  Wait for user confirmation (y).

`n`[`c`]

  Select tape drive `n` and use speed `c`. `n` is 0-7 (default is 0); `c` is l (low) h (high) m (medium, the default). Used to modify `arch`.

### Examples

Create an archive of /bin and /usr/bin (c), show the command working (v), and store on the tape in /dev/rmt0:

>     tar cvf /dev/rmt0 /bin /usr/bin

List the tape's contents in a format like ls -l:

>     tar tvf /dev/rmt0

Extract the /bin directory:

>     tar xvf /dev/rmt0 /bin

Create an archive of the current directory, and store it in a file backup.tar on the system.

>     tar cvf - `find . -print` > backup.tar

(The - tells tar to store the directory on standard output, which is then redirected.)

Reference: talk |  | Reference: tbl