Re: feedback as solicited by Guix manual (Section 7.1.5)

[Alex Kost <alezost@gmail.com>]

Ludovic Courtès (2016-06-03 11:11 +0300) wrote:

> Alex Kost <alezost@gmail.com> skribis:
[...]
>> Wow, do you mean that ifconfig is not only for Linux kernel?
>
> Exactly.
>
> Under the hood, ‘ip’ uses Linux-specific netlink socket interfaces,
> whereas GNU ifconfig uses the good ol’ ioctls that most Unices support
> (including GNU/Hurd):
>
>
> ~$ sudo strace -e socket ip a
> socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, 0) = 3
> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
>     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
>     inet 127.0.0.1/8 scope host lo
>        valid_lft forever preferred_lft forever
>     inet6 ::1/128 scope host 
>        valid_lft forever preferred_lft forever
> 2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
>     link/ether 5c:26:0a:64:07:23 brd ff:ff:ff:ff:ff:ff
>     inet 193.50.110.57/24 brd 193.50.110.255 scope global eno1
>        valid_lft forever preferred_lft forever
>     inet6 fe80::5e26:aff:fe64:723/64 scope link 
>        valid_lft forever preferred_lft forever
> 3: wlp0s29u1u2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
>     link/ether 60:02:b4:99:9b:31 brd ff:ff:ff:ff:ff:ff
> +++ exited with 0 +++
> ludo@pluto ~$ sudo strace -e ioctl ifconfig -a
> ioctl(3, SIOCGIFINDEX, {ifr_name="wlp0s29u1u2", ifr_index=3}) = 0
> ioctl(3, SIOCGIFINDEX, {ifr_name="lo", ifr_index=1}) = 0
> ioctl(3, SIOCGIFINDEX, {ifr_name="eno1", ifr_index=2}) = 0
> ioctl(5, SIOCGIFINDEX, {ifr_name="eno1", ifr_index=2}) = 0
> ioctl(4, SIOCGIFHWADDR, {ifr_name="eno1", ifr_hwaddr=5c:26:0a:64:07:23}) = 0
> ioctl(4, SIOCGIFHWADDR, {ifr_name="eno1", ifr_hwaddr=5c:26:0a:64:07:23}) = 0
> ioctl(4, SIOCGIFHWADDR, {ifr_name="eno1", ifr_hwaddr=5c:26:0a:64:07:23}) = 0
> ioctl(4, SIOCGIFHWADDR, {ifr_name="eno1", ifr_hwaddr=5c:26:0a:64:07:23}) = 0
> eno1      Link encap:Ethernet  HWaddr 5C:26:0A:64:07:23
>
> [...]
>
>
>> If ifconfig is a general thing (suitable for Hurd) then I agree; we
>> should probably leave it as it is now.  Otherwise I would also add a
>> mention how to do it with "ip", like this:
>
>
> diff --git a/doc/guix.texi b/doc/guix.texi
> index c8c7555..12dd354 100644
> --- a/doc/guix.texi
> +++ b/doc/guix.texi
> @@ -6010,6 +6010,13 @@ Run the following command see what your network interfaces are called:
>  ifconfig -a
>  @end example
>  
> +@noindent
> +@dots{} or, using the GNU/Linux-specific @command{ip} command:
> +
> +@example
> +ip a
> +@end example
> +
>  @c http://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
>  Wired interfaces have a name starting with @samp{e}; for example, the
>  interface corresponding to the first on-board Ethernet controller is
>
> OK with this?

As for me, I'm absolutely OK with this.  And thanks for the explanation
that ifconfig is a more general tool.

-- 
Alex