Re: [PATCH v5] net: ip, diag -- Add diag interface for raw sockets

[Jamal Hadi Salim]

On 16-09-28 08:27 AM, Jamal Hadi Salim wrote:
> On 16-09-28 08:16 AM, David Miller wrote:
> > From: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
> > Date: Wed, 28 Sep 2016 08:09:28 -0400
> >
> > > On 16-09-28 08:07 AM, David Miller wrote:
> > >
> > > > Right, it would be legal for an existing user to have code that
> > > > explicitly initializes every member of the structure, including 'pad'.
> > > > So we have to keep that member around, at a minimum, for their sake.
> > >
> > > I think we need to start labelling any new pad fields added as
> > > "Not UAPI. Do not fsck fondle this".
> >
> > They must initialize it to zero.
>
> What if in the future actually meant to use 0 for
> something?;-> For example in Cyrill's case it means PROTO_IP
> Not sure if it useful to interpret or not but it is part of the
> enum for protocols.

I just tested with: socket(AF_INET, SOCK_RAW, 0);

and got back: EPROTONOSUPPORT

So in this case doesnt matter. But my point stands i.e 0 could mean
something.

cheers,
jamal