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This article introduces the relevant knowledge of "how linux uses tar commands to package or back up files". In the operation of actual cases, many people will encounter such a dilemma, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

How do I use the tar command to package (back up) files?

A:The syntax of tar is:

Tar [options] [files]

The options used most often with tar are as follows:

C Creates a new backup,overwriting any files already on the backup destination.

X Extracts files from backup media.

T Lists the contents of backup media.

V Displays the name of each file being processed.

F Creates backups on a specified device.

U Adds files to the backup if they are not already there,or if they have been modified since they were last written on the backup.

Steps:

1) estimate the size of the packaged file, determine the space to use archival media (archive media), and use the command du-s

For example:

$lf

A.outout * fork.c mbox time.c

Atoi.c int.c memcpy.c vi

$du-s

296.

$

The 296 shown in this example stands for the total number of 512-byte blocks, calculated as 512*296/1024=148kilobytes.

2) make a backup and use the command tar cvf / dev/fd0135ds18. (backup all the contents of this directory to a 1.44in floppy disk where c causes a new backup to be created,v causes each file to be displayed as the backing up takes place,and f causes the subsequent argument--/dev/fd0135ds18 to be the destination of the backup.)

Note: we usually use the command tar cvf filename.tar for the backup on the hard disk.

For example:

$tar cvf wuyd.tar.

A. / .profile 2 tape blocks

A. / .lastlogin 0 tape blocks

A. / mbox 10 tape blocks

A. / fork.c 2 tape blocks

A. / memcpy.c 1 tape blocks

A. / .sh _ history 3 tape blocks

A. / a.out 91 tape blocks

A. / time.c 1 tape blocks

A. / vi 169 tape blocks

A. / int.c 1 tape blocks

A. / atoi.c 1 tape blocks

Tar: same as archive file:. / wuyd.tar

A. / .scoadmin.pref 1 tape blocks

$lf

A.outout * fork.c mbox time.c wuyd.tar

Atoi.c int.c memcpy.c vi

We can also back up the file named filename in this directory to archive media with the command tar cvf / dev/fd0135ds18. / filename

How do I list the contents of an tar document?

A:tar tvf / dev/fd0135ds18

Tar tvf filename.tar

For example:

$tar tvf wuyd.tar

Tar: blocksize = 20

Rw-203/50 896 Sep 17 15:07 2003. / .profile

RMur203Compare 21 0 Sep 24 19:49 2003. / .lastlogin

Rw-203/50 4720 Sep 21 11:17 2003. / mbox

Rw-r--r--203/50 583 Sep 17 15:27 2003. / fork.c

Rw-r--r--203/50 218 Sep 17 20:22 2003. / memcpy.c

Rw-203/50 1474 Sep 24 20:26 2003. / .sh _ history

Rwxr-xr-x203/50 46224 Sep 22 21:00 2003. / a.out

Rw-r--r--203/50 341 Sep 19 09:02 2003. / time.c

Rw-r--r--203/50 86283 Sep 21 09:14 2003. / vi

Rw-r--r--203/50 93 Sep 21 10:53 2003. / int.c

Rw-r--r--203/50 144 Sep 22 21:00 2003. / atoi.c

Rw-r--r-- 0/3 41 Sep 23 20:34 2003. / .scoadmin.pref

$

How do I export a file from an tar document?

A:tar xvf / dev/fd0135ds18

Tar xvf filename.tar

For example:

$mkdir uu;cp wuyd.tar. / uu

$lf

A.outout * fork.c mbox time.c vi

Atoi.c int.c memcpy.c uu/ wuyd.tar

$cd uu

$tar xvf wuyd.tar

Tar: blocksize = 20

X. / .profile, 896 bytes, 2 tape blocks

X. / .lastlogin, 0 bytes, 0 tape blocks

X. / mbox, 4720 bytes, 10 tape blocks

X. / fork.c, 583 bytes, 2 tape blocks

X. / memcpy.c, 218 bytes, 1 tape blocks

X. / .sh _ history, 1474 bytes, 3 tape blocks

X. / a.out, 46224 bytes, 91 tape blocks

X. / time.c, 341 bytes, 1 tape blocks

X. / vi, 86283 bytes, 169 tape blocks

X. / int.c, 93 bytes, 1 tape blocks

X. / atoi.c, 144 bytes, 1 tape blocks

X. / .scoadmin.pref, 41 bytes, 1 tape blocks

$

We can export a single file in archive media with the command tar xvf / dev/fd0135ds18. / filename

For example:

$lf

Wuyd.tar

$tar xvf wuyd.tar. / time.c

Tar: blocksize = 20

X. / time.c, 341 bytes, 1 tape blocks

$lf

Time.c wuyd.tar

$

How do I use the abbreviated form provided by the tar command?

A:

$more / etc/default/tar

# @ (#) def135.src 25.2 94-07-25

#

# Copyright (C) 1987-1994 The Santa Cruz Operation, Inc.

# All Rights Reserved.

# The information in this file is provided for the exclusive use of

# the licensees of The Santa Cruz Operation, Inc. Such users have the

# right to use, modify, and incorporate this code into other products

# for purposes authorized by the license agreement provided they include

# this notice and the associated copyright notice with any such product.

# The information in this file is provided "AS IS" without warranty.

#

# default/tar-archive devices: tar (C)

#

# device block size tape

#

Archive0=/dev/rfd048ds9 18 360 n

Archive1=/dev/rfd148ds9 18 360 n

Archive2=/dev/rfd096ds15 10 1200 n

Archive3=/dev/rfd196ds15 10 1200 n

# archive4=/dev/rfd096ds9 18 720 n

Archive4=/dev/rfd0135ds9 18 720 n

Archive5=/dev/rfd1135ds9 18 720 n

# archive5=/dev/rfd196ds9 18 720 n

Archive6=/dev/rfd0135ds18 18 1440 n

Archive7=/dev/rfd1135ds18 18 1440 n

Archive8=/dev/rct0 20 0 y

Archive9=/dev/rctmini 20 0 y

Archive10=/dev/rdsk/fp03d 18 720 n

Archive11=/dev/rdsk/fp03h 18 1440 n

Archive12=/dev/rdsk/fp03v21 10 20330 n

#

# The default device in the absence of a numeric or "- f device" argument

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