[Paranoia] sg_write kernel logging flood

[Douglas Gilbert]

xiphmont at xiph.org wrote:
> On 7/19/07, Tobias Jakobi <liquid.acid at gmx.net> wrote:
>> Hi Pim,
>>
>> I've just downloaded the current cdparanoia source from SVN and it did
>> indead compile fine. But I still get the kernel flooding.
> 
> I expect you have an old version still installed and the version of
> the interface lib installed in /usr/lib is being used over the version
> of the interface lib you built and installed on /usr/local/lib.  Use
> ldd to make sure.
> 
> The SVN version will always prefer SGIO over SG.

I think I know what you mean. The SG_IO ioctl was first introduced
in sg driver at the start of the lk 2.4 series. By the start of
the lk 2.6 series the SG_IO ioctl was _also_ found in the block layer
(and the st and osst drivers, amongst others).

So it should be safe to use the SG_IO ioctl on any device given
by the user in the cdparanoia invocation. If it fails, then it
is only worth trying the async write()/read() interface
   a) the device given is a sg node,and
   b) 1) the app need async, or
      2) a lk 2.2 (or lk 2.0) series kernel is detected


Doug Gilbert