[FFmpeg-devel] [PATCH] Return ENOTSUP if codec does not support feature

Michael Niedermayer michaelni
Fri Jul 20 19:04:06 CEST 2007


On Fri, Jul 20, 2007 at 06:13:34PM +0200, Panagiotis Issaris wrote:
> Hi
> Op 20-jul-07, om 18:05 heeft Ronald S. Bultje het volgende geschreven:
> > Hi,
> >
> > On 7/20/07, Panagiotis Issaris <takis.issaris at uhasselt.be> wrote:
> >>
> >> Hmm. I interpreted this differently, namely as codec x does not
> >> support feature y: "Codec H263 does not support feature 4MV", "Codec
> >> FLV1 does not support feature 4MV", etc..
> >
> >
> > That is EINVAL, since the requested parameter, the unsupported  
> > feature, is
> > invalid for this codec. ENOTSUP means that the implementation isn't
> > supported, even though plainly speaking, the parameters would have  
> > been
> > valid for a complete implementation.
> Do you know a source for the correct and exact meaning of these  
> codes? I am only aware of the OpenGroup's website, but the  
> definitions on that site aren't really clear:
> [ENOTSUP] Not supported.
> [ENOSYS] Function not supported.
> [EINVAL] Invalid argument.
> ...
> As can be found here:
> http://www.opengroup.org/onlinepubs/009695399/basedefs/errno.h.html
> If you were referring to the definition in the libc infopages, I'd  
> interpreted them differently. It says (notice the empasis I added):
> "... the functionality they request is not available. This _can_ mean  
> that the function does not implement a particular command ..."

-- Macro: int ENOTSUP
     Not supported.  A function returns this error when certain
     parameter values are valid, but, the functionality they request is
     not available. ...

interlacing with mpeg1 is not valid for example

Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Good people do not need laws to tell them to act responsibly, while bad
people will find a way around the laws. -- Plato
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20070720/e915acd8/attachment.pgp>

More information about the ffmpeg-devel mailing list