pSOSystem System Calls - Read

setsockopt pNA+ System Calls
IP_ADD_MEMBERSHIP_INTF Similar to IP_ADD_MEMBERSHIP above. The
optval is a pointer to the structure
ip_mreq_intf (defined in ). The only
difference is that the interface is defined using
the interface number. If the interface number is
specified as -1 then pNA+ will select the interface
based upon the routing table. This option is useful
for unnumbered links because the IP address
of the interface is not enough to identify the interface.
The structure below is defined in and
used with the IP_ADD_MEMBERSHIP_INTF option.
struct ip_mreq_intf {
struct in_addr imrif_mcastaddr;
/* IP multicast address of group */
long imrif_ifno;
/* local interface number */
};
IP_DROP_MEMBERSHIP Leave a multicast group. optval is a pointer to
the ip_mreq structure (defined in ). The
group multicast address to be dropped must be
specified in imr_mcastaddr. The interface address
could be set to INADDR_ANY unless it specifies
the particular interface for which the group
membership must be dropped.
The structure below is defined in and
used with the IP_DROP_MEMBERSHIP option.
struct ip_mreq {
struct in_addr imr_mcastaddr;
/* IP multicast address of group */
struct in_addr imr_interface;
/* local IP address of interface */
};
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