Re: [PATCH] make st seekable again

[Bodo Eggert <7eggert@gmx.de>]

Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> On Maw, 2005-03-08 at 17:25, Linux Kernel Mailing List wrote:
>> ChangeSet 1.2030, 2005/03/08 09:25:05-08:00, kai.makisara@kolumbus.fi

>> [PATCH] make st seekable again
>> 
>> Apparently `tar' errors out if it cannot perform lseek() against a tape. 
>> Work around that in-kernel.
> 
> Unfortunately this isn't a good idea. Allowing tar to read the tape
> position makes sense, allowing it to zero the position might but you
> have to do major surgery on the driver first because
> 
> 1.    It doesn't use ppos
> 2.    It doesn't do locking on the ppos at all
> 
> Also allowing apps to randomly seek and report "ok" when they are
> backing up to tape and might really need to see the error is not what
> I'd call stable, professional or quality code.

Can the lseek be restricted to seek from 0 to 0 (or even * to 0 aka rewind)?
This would re-enable tar and probably other applications depending on this
API while not giving them false positives.