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tar
SYNTAX
tar [option(s)] [files]
FUNCTION
tar - tape archiver saves and restores files on magnetic tapes,
disks, data cartridges and other files or groups of files.
Note:
The default archive is made on magnetic tape.
OPTIONS
r - The named files are to be written to the
end of the archive.
x - The named files are extracted from the archive.
If none are specified then all are extracted. If
a named file matches a directory whose contents
had been written onto the archive, this directory
is recursively extracted.
t - The named files are listed each time they
occur in the archive. If none are specified,
then all are listed.
u - The named files are added to the archive if
they are not already there.
c - Creates a new archive; writing begins at
the beginning of the specified archive.
FUNCTION MODIFIERS
Function modifiers are used along with the options. The
modifier arguments must be in the same order as the
modifiers themselves.
0,..,7 - selects the drive on which the tape is
mounted
v - (verbose) causes tar to print the name of
each treated file along with the action
w - causes tar to work interactively and to
obey the orders of user's response
f - causes tar to use the next argument as
the name of a file instead of /dev/mt?
FUNCTION MODIFIERS (continued)
b - causes tar to use the next argument as
the blocking factor for archive records.
The default is 1, the maximum is 20
p - causes files to be extracted with their
original permissions. This may prevent
a non-superuser from extracting the
files because of permission
k - causes tar to use the next argument as the
size of the archive volume in kilobytes
m - tells tar not to restore modification times
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cti miked yori
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842 843 851
If a portion of the file
system is as shown below,
then the command for verbose
creation of a new archive file
/dev/rfd0 with a blocking
factor of 20, of the
subdirectory cti is?
$PROMPT$
That is correct!
You've got it on the 2nd try.
Good, you understand the concept.
No, note that modifiers and arguments are order dependent.
The command and modifiers are tar cvbf, you do the rest!
You will be helped this time!
$PROMPT$
FORGET1
$PROMPT$tar cvbf 20 /dev/rfd0 cti
Observe the result on the terminal
a cti/842 32 tape blocks
a cti/843 23 tape blocks
a cti/851 14 tape blocks
$PROMPT$
On the other hand, if a portion of the hypothetical
file system tree had the form shown above, let
us see what kind of result would be produced by
verbosely extracting the archive file /dev/rfd0.
/
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cti miked yori
$PROMPT$
That is correct!
You've got it on the 2nd try.
Good, you understand the concept.
No, we will be extracting from a file.
The first portion of the command is tar xvf.
You will be helped this time!
$PROMPT$
FORGET2
$PROMPT$tar xvf /dev/rfd0
x cti/842
x cti/843
x cti/851
Observe the command effect on the diagram above:
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