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From: mark@zok.UUCP (Mark W. Snitily)
Newsgroups: comp.unix.i386
Subject: Re: dd curiosity
Message-ID: <397@zok.UUCP>
Date: 31 Dec 89 22:08:01 GMT
References: <396@zok.UUCP> <1989Dec30.233951.23096@twwells.com>
Reply-To: mark@zok.UUCP (Mark W. Snitily)
Organization: The distant planet Zok
Lines: 28

In article <1989Dec30.233951.23096@twwells.com> bill@twwells.com (T. William Wells) writes:
>In article <396@zok.UUCP> mark@zok.UUCP (Mark W. Snitily) writes:
>: But, if I read 4 sectors from the partition starting at sector 20000,
>: the read will take forever to complete, (i.e. we're talking minutes to
>: hours depending upon the skip value):
>:       dd if=/dev/rdsk/0p1 of=myfile skip=20000 count=4
>
>Reads everything from the beginning of /dev/rdsk/0p1 till it gets
>to the place to read.
>
>: Any ideas of how to speed it up?
>
>Use seek instead of skip.

Thanks for the suggestion, but quoting from the manual:
    skip=n   skips n input blocks before starting copy
    seek=n   seek n blocks from beginning of output file before copying

"skip" applies to the input file.  "seek" applies to the output file.
What I'd like to have is a "seek" performed on the input file.
Ideas anyone?

-- Mark

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