Use ioctl() to list all network interfaces.

Use ioctl() to list all network interfaces.

[Chin Shi Hong]

Dear all,

The following codes are just part of my application's source codes:

--begin of some codes--
ifconf ifc;
ret = ioctl(n, SIOCGIFCONF,&ifc);
--End of some codes--

My application's role is to display all network interfaces, including
the network interface which are down.

However, with the above codes, my application only display the network
interface which are already up. The network interface which are down
will not be displayed.

So, what can I do to make my application display all network
interfaces, including the network interface which are down?

regards,

Re: Use ioctl() to list all network interfaces.

[Rémi Denis-Courmont]

Le jeudi 6 janvier 2011 17:33:39 Chin Shi Hong, vous avez écrit :
> My application's role is to display all network interfaces, including
> the network interface which are down.

You should use if_nameindex() then.

-- 
Rémi Denis-Courmont
http://www.remlab.net/
http://fi.linkedin.com/in/remidenis

Re: Use ioctl() to list all network interfaces.

[Alexander Clouter]

Chin Shi Hong <cshong87@gmail.com> wrote:
>
> The following codes are just part of my application's source codes:
> 
> --begin of some codes--
> ifconf ifc;
> ret = ioctl(n, SIOCGIFCONF,&ifc);
> --End of some codes--
> 
> My application's role is to display all network interfaces, including
> the network interface which are down.
> 
> However, with the above codes, my application only display the network
> interface which are already up. The network interface which are down
> will not be displayed.
> 
> So, what can I do to make my application display all network
> interfaces, including the network interface which are down?
>
getifaddrs(), you get the IPv6 ones too this way.

Cheers

-- 
Alexander Clouter
.sigmonster says: I've only got 12 cards.

Re: Use ioctl() to list all network interfaces.

[Chin Shi Hong]

2011/1/7 Rémi Denis-Courmont <remi@remlab.net>:
> Le jeudi 6 janvier 2011 17:33:39 Chin Shi Hong, vous avez écrit :
>> My application's role is to display all network interfaces, including
>> the network interface which are down.
>
> You should use if_nameindex() then.
>
> --
> Rémi Denis-Courmont
> http://www.remlab.net/
> http://fi.linkedin.com/in/remidenis
>

Thank you. if_nameindex() really help me.

Regards,

Re: Use ioctl() to list all network interfaces.

[Chin Shi Hong]

On Fri, Jan 7, 2011 at 1:07 AM, Alexander Clouter <alex@digriz.org.uk> wrote:
> Chin Shi Hong <cshong87@gmail.com> wrote:
>>
>> The following codes are just part of my application's source codes:
>>
>> --begin of some codes--
>> ifconf ifc;
>> ret = ioctl(n, SIOCGIFCONF,&ifc);
>> --End of some codes--
>>
>> My application's role is to display all network interfaces, including
>> the network interface which are down.
>>
>> However, with the above codes, my application only display the network
>> interface which are already up. The network interface which are down
>> will not be displayed.
>>
>> So, what can I do to make my application display all network
>> interfaces, including the network interface which are down?
>>
> getifaddrs(), you get the IPv6 ones too this way.
>
> Cheers
>
> --
> Alexander Clouter
> .sigmonster says: I've only got 12 cards.
>
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

getifaddrs() helpful also. Thank you!

Regards,