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PAGETURNER
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$PROMPT$
That is correct!
You've got it on the 2nd try.
Good, you understand the concept.
Please type
$COMMAND$
Please type
$COMMAND$
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FORGET1
$PROMPT$$COMMAND$
Observe the result above.
$PROMPT$
BOX
COMMAND
GO
Remember, we mentioned that there are basically two methods for
duplicating media. The first was with tar. The second is with the
dd utility. On systems with TWO tape/cartridge/disk drives you
may copy from one to the other using dd. You may also copy directly
from the tape drive to a data cartridge drive, or from a disk drive
to a data cartridge drive, etc. We'll use duplicating a tape for our
example, however, you may use this procedure for other devices as well.
dd
SYNTAX
dd [option=value] ...
FUNCTION
dd copies the specified input file to the specified output
file with possible conversions. The standard input and output
are used by default.
OPTIONS
option values
if=name input file is name; standard input is default
of=name output file is name; standard output is default
ibs=n input block size of n bytes (default 512)
obs=n output block size (default 512)
files=n copy n input files before terminating.
The dd command has many qualifiers and specifiers.
Let us briefly cover a few.
* The if (input file) option allows you to read
from the named file, instead of standard input.
* The of (output file) option allows you to write
to the named file, instead of standard output.
* The ibs (input block size) option specifies
the block size of the input media.
* The obs (output block size) option specifies
the block size of the output media.
Assume that you have only one tape drive, so you'll have to copy
your tape onto the disk, mount a new tape, and copy the disk file
onto the new tape. To copy the contents of a tape mounted on drive
rmt0 (input block size=10240) to a file called foo on the disk,
you would enter:
dd if=/dev/rmt0 of=foo ibs=10240
* The if= option tells dd that the input will come
from tape drive /dev/rmt0 rather than the standard input.
* The of= option tells dd that the output will go
to the file foo rather than the standard output.
* The ibs= option tells dd that the input block
size is 10240.
To copy the disk file back onto a new tape, your would mount the tape
and enter:
dd if=foo of=/dev/rmt0 obs=10240
Let us use the dd command to
copy a tape mounted on /dev/rmt0
onto the disk to a file called
tape. Assume that the input
block size is 10240.
<CR> - to continue