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Cc: tim@kientzle.com, freebsd-arch@freebsd.org
Subject: Re: [PATCH] fadvise(2) system call
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Warner Losh <imp@bsdimp.com> wrote:
> On Nov 12, 2011, at 3:17 AM, perryh@pluto.rain.com wrote:
> > Peter Wemm <peter@wemm.org> wrote:
> >> On Fri, Nov 11, 2011 at 4:08 PM, Tim Kientzle <tim@kientzle.com>
> >> wrote:
> >>> ... seek(2) is badly broken on tape drives.
> >>> It does nothing and doesn't return an error ...
> >> 
> >> Honestly, I think we've got bigger problems to worry about
> >> than whether lseek() works on magnetic tape drives ...
> > 
> > True, but failing silently -- doing nothing but not returning an
> > error -- is a POLA violation.  Those are worth fixing simply on
> > principle.
>
> Early Unix layering made that kinda hard... :(

and yet, it somehow manages to return an error if applied to a pipe.
There must be some point at which the inode type affects the result.