Hi Pali,
Please, see some comments below.
On 1/2/21 3:02 PM, Pali Rohár wrote:
> Also add description for struct in6_ifreq which is used for IPv6 addresses.
>
> SIOCSIFADDR and SIOCDIFADDR can be used to add or delete IPv6 address and
> pppd is using these ioctls for a long time. Surprisingly SIOCDIFADDR cannot
> be used for deleting IPv4 address but only for IPv6 addresses.
>
> Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
> ---
> man7/netdevice.7 | 36 +++++++++++++++++++++++++++++-------
> 1 file changed, 29 insertions(+), 7 deletions(-)
>
> diff --git a/man7/netdevice.7 b/man7/netdevice.7
> index 488e83d9a..5b68e4988 100644
> --- a/man7/netdevice.7
> +++ b/man7/netdevice.7
> @@ -55,9 +55,27 @@ struct ifreq {
> .EE
> .in
> .PP
> +Exception is
> +.B AF_INET6
> +socket for which is used
> +.I in6_ifreq
> +structure:
Wording fix:
[
AF_INET6 is an exception.
It passes an
.I in6_ifreq
structure:
]
Are there more exceptions?
Or is it the only one?
> +.PP
> +.in +4n
> +.EX
> +struct in6_ifreq {
> + struct in6_addr ifr6_addr;
> + u32 ifr6_prefixlen;
> + int ifr6_ifindex; /* Interface index */
> +};
> +.EE
> +.in
> +.PP
> Normally, the user specifies which device to affect by setting
> .I ifr_name
> -to the name of the interface.
> +to the name of the interface or
> +.I ifr6_ifindex
> +to the index of the interface.
I've seen there's ifr_ifindex too (see SIOCGIFNAME).
Can it be used in the same way as ifr6_ifindex?
> All other members of the structure may
> share memory.
> .SS Ioctls
> @@ -142,13 +160,17 @@ IFF_ISATAP:Interface is RFC4214 ISATAP interface.
> .PP
> Setting the extended (private) interface flags is a privileged operation.
> .TP
> -.BR SIOCGIFADDR ", " SIOCSIFADDR
> -Get or set the address of the device using
> -.IR ifr_addr .
> -Setting the interface address is a privileged operation.
> -For compatibility, only
> +.BR SIOCGIFADDR ", " SIOCSIFADDR ", " SIOCDIFADDR
> +Get, set or delete the address of the device using
> +.IR ifr_addr " or " ifr6_addr " with " ifr6_prefixlen .
Generally, we place each name on a single line.
The line after .TP is an exception, as you can see above.
So this would be:
[
.IR ifr_addr ,
or
.I ifr6_addr
with
.IR ifr6_prefixlen .
]
> +Setting or deleting the interface address is a privileged operation.
> +For compatibility,
> +.BR SIOCGIFADDR " returns only " AF_INET " addresses, "
> +.BR SIOCSIFADDR " accepts " AF_INET " and " AF_INET6 " addresses and "
> +.BR SIOCDIFADDR " deletes only " AF_INET6 " addresses. "
See above.
> .B AF_INET
> -addresses are accepted or returned.
> +address can be deleted by setting zero address via
> +.BR SIOCSIFADDR .
> .TP
> .BR SIOCGIFDSTADDR ", " SIOCSIFDSTADDR
> Get or set the destination address of a point-to-point device using
>
Thanks,
Alex
--
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
http://www.alejandro-colomar.es/
