SO_BINDTODEVICE socket option on an aliased interface

Hi,
I do something like :

char * device = "eth0:1";
int s;
s = socket(PF_INET, SOCK_STREAM, 0);
if (setsockopt(s, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device)))
perror("setsockopt");

the result is:
setsockopt: No such device

Why?
SO_BINDTODEVICE is not supposed to work on an aliased interface?

Regards,
Christophe.

On Jan 16, 4:44*am, Christophe Lohr <christophe.l...@enst-bretagne.fr>
wrote:

> char * device = "eth0:1";
> int s;
> s = socket(PF_INET, SOCK_STREAM, 0);
> if (setsockopt(s, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device)))
> * * perror("setsockopt");

> the result is:
> * setsockopt: No such device

> Why?
> SO_BINDTODEVICE is not supposed to work on an aliased interface?

Just bind to the main interface. The aliased interface is an alias for
the main interface, that is, it's another name for the same interface.

DS

David Schwartz a écrit :
> On Jan 16, 4:44 am, Christophe Lohr <christophe.l...@enst-bretagne.fr>
>> SO_BINDTODEVICE is not supposed to work on an aliased interface?
>
> Just bind to the main interface. The aliased interface is an alias for
> the main interface, that is, it's another name for the same interface.

Ok.

I have another question: according to man socket(7), it is not
supported for packet sockets. So, why? (It's not yet implmented, or is
it impossible?)

Regards
Christophe.

Christophe Lohr a écrit :
> David Schwartz a écrit :
>> On Jan 16, 4:44 am, Christophe Lohr <christophe.l...@enst-bretagne.fr>
>>> SO_BINDTODEVICE is not supposed to work on an aliased interface?
>> Just bind to the main interface. The aliased interface is an alias for
>> the main interface, that is, it's another name for the same interface.
>
> Ok.
>
> I have another question: according to man socket(7), it is not
> supported for packet sockets. So, why? (It's not yet implmented, or is
> it impossible?)

I have a new question (again): what is the behavior of outgoing packets?
Are they routed through the given interface?

Regards.

On Jan 23, 4:59*am, Christophe Lohr <christophe.l...@enst-bretagne.fr>
wrote:

> I have a new question (again): what is the behavior of outgoing packets?
> Are they routed through the given interface?

If they can be routed, they will be routed through the best interface.
If they cannot be routed, the given interface will be used. (For
example, an arbitrary Ethernet packet that is not in a protocol known
to the OS cannot be routed by the OS.)

DS