#include <rtl.h>

BOOL igmp_leave (
    U8  *group_ip);     /* IP Address of the Host Group. */

The igmp_leave function requests that this host gives up its membership in the host group identified by group_ip. After the upper-layer has requested to leave the host group, datagrams destined to a particular group can not be received, but are silently discarded by the IP-layer.

The igmp_leave function is in the RL-TCPnet library. The prototype is defined in rtl.h.

The igmp_leave function returns __TRUE when this host successfully left a host group. Otherwise, the function returns __FALSE.

igmp_join, udp_mcast_ttl, udp_send

U8 sgroup[4] = { 238, 0, 100, 1};
 ..
if (igmp_leave (sgroup) == __TRUE) {
  printf ("This Host has left the group: %d.%d.%d.%d\n",
           sgroup[0],sgroup[1],sgroup[2],sgroup[3]);
}
else {
  printf ("Failed to leave a group, this host is not a member.\n");
}