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From: Warner Losh <imp@bsdimp.com>
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References: <201110281426.00013.jhb@freebsd.org> <4EB2C9DD.9090606@FreeBSD.org>
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To: Tim Kientzle <tim@kientzle.com>
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Cc: Bruce Cran <bruce@cran.org.uk>, Ed Schouten <ed@80386.nl>,
	Jilles Tjoelker <jilles@stack.nl>,
	Alfred Perlstein <alfred@FreeBSD.org>, arch@FreeBSD.org,
	freebsd-arch@FreeBSD.org
Subject: Re: [PATCH] fadvise(2) system call
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On Nov 9, 2011, at 11:03 PM, Tim Kientzle wrote:
> Anyone know how to properly request a "skip forward"
> on tape drives?  That's one of the missing pieces.

I thought that you couldn't seek(2) on tape drives.  You must read(2) =
the data.  At least for this application, since a tar file would be just =
one file on the tape.  If you want to see to the next file mark, you =
need to use an ioctl to get there, or read a lot.

Warner