On Thu, Jan 07, 2021 at 04:03:41PM +0100, Claudio Jeker wrote:
> Here is my try to extend ip(4) to also document struct ip_mreqn.
> Not sure what is the best way to document the option to use either struct
> ip_mreq or struct ip_mreqn with IP_ADD_MEMBERSHIP.
>
> --
> :wq Claudio
>
hi! comments inline:
> Index: ip.4
> ===================================================================
> RCS file: /cvs/src/share/man/man4/ip.4,v
> retrieving revision 1.41
> diff -u -p -r1.41 ip.4
> --- ip.4 18 Aug 2016 11:45:18 -0000 1.41
> +++ ip.4 7 Jan 2021 14:58:54 -0000
> @@ -411,13 +411,21 @@ setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERS
> .Pp
> where
> .Fa mreq
> -is the following structure:
> +is either the following structure:
we could probably tidy this up:
...
is either of the following structures:
.Bd ...
<both structures in here>
.Ed
> .Bd -literal -offset indent
> struct ip_mreq {
> struct in_addr imr_multiaddr; /* multicast group to join */
> struct in_addr imr_interface; /* interface to join on */
> }
> .Ed
> +or
> +.Bd -literal -offset indent
> +struct ip_mreqn {
> + struct in_addr imr_multiaddr; /* multicast group to join */
> + struct in_addr imr_address; /* local IP address of interface */
> + int imr_ifindex; /* interface index to join*/
space between "join" and "*"
> +};
> +.Ed
> .Pp
> .Va imr_interface
> should
> @@ -428,6 +436,12 @@ or the
> .Tn IP
> address of a particular multicast-capable interface if
> the host is multihomed.
> +.Va imr_ifindex
> +of
> +.Va struct ip_mreqn
this reads funny. maybe
The
.Va imr..
element of
.Va struct...
or similar wording
> +can be set to the interface index instead of specifying the
> +.Tn IP
> +address of a particular multicast-capable interface.
> Membership is associated with a single interface;
> programs running on multihomed hosts may need to
> join the same group on more than one interface.
>
jmc
